Low furnace PSI
#1
09-16-10, 05:19 PM
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Low furnace PSI
Hey guys,
With winter approaching, I want to tune up the old burner. It is a Weil Mcclain gas fired furnace.
Of interest, I am reading just about 0 psi on the temp/pressure gauge on the side of the unit. When I bought the house a year ago, I was told it was just checked and read 18 psi... Either the gauge is busted, or I have a pressure problem. I opened the fill system fill valve and it did flow, and it does not seem to be leaking. Maybe it will not maintain 12-15 psi???
I have a water pressure gauge I could attach to one of the drains to test the pressure. Would this be a good first step?
Thanks Guys,
Bryan
With winter approaching, I want to tune up the old burner. It is a Weil Mcclain gas fired furnace.
Of interest, I am reading just about 0 psi on the temp/pressure gauge on the side of the unit. When I bought the house a year ago, I was told it was just checked and read 18 psi... Either the gauge is busted, or I have a pressure problem. I opened the fill system fill valve and it did flow, and it does not seem to be leaking. Maybe it will not maintain 12-15 psi???
I have a water pressure gauge I could attach to one of the drains to test the pressure. Would this be a good first step?
Thanks Guys,
Bryan
#2
09-16-10, 05:29 PM
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OK,
I just tried measuring pressure at both the large return pipe leading into the burner, and from two of the three zone drain valves.
The pressure is reading 0 psi. I get 45-60 psi when I read my outdoor spiggot, so I know the gauge works.
I tried adding some more water via the auto fill switch and the pressure came up a bit, but won't go up over about 10-12 psi.
I tried bleeding the upstairs radiators, and there was a little pressure, a small amount of air came out, and then a little water. The pressure then dropped to about 8 psi.
The heat is working, albeit weakly, but my concern is that the pressure drops or will not go above 12 psi.
What should the pressure be to keep this working on the second floor?
Could there be a problem with the expansion tank... I tried bleeding air from above it, was that a mistake? If the expansion tank looses pressure, will the system not fill?
Thanks,
Bryan
I just tried measuring pressure at both the large return pipe leading into the burner, and from two of the three zone drain valves.
The pressure is reading 0 psi. I get 45-60 psi when I read my outdoor spiggot, so I know the gauge works.
I tried adding some more water via the auto fill switch and the pressure came up a bit, but won't go up over about 10-12 psi.
I tried bleeding the upstairs radiators, and there was a little pressure, a small amount of air came out, and then a little water. The pressure then dropped to about 8 psi.
The heat is working, albeit weakly, but my concern is that the pressure drops or will not go above 12 psi.
What should the pressure be to keep this working on the second floor?
Could there be a problem with the expansion tank... I tried bleeding air from above it, was that a mistake? If the expansion tank looses pressure, will the system not fill?
Thanks,
Bryan
#3
09-16-10, 07:17 PM
On a factory set fill pressure reg you will only get about 12 psi. I think its 12 -15 PSI set from the factory.
You only need the pressure to lift the water column up to the highest rad, since it's a closed system you don't need the pressure to move the water.
You only need the pressure to lift the water column up to the highest rad, since it's a closed system you don't need the pressure to move the water.
#4
09-17-10, 05:15 AM
Yes, it was a mistake to let any air out of the expansion tank.
You may have what is called a 'Fill-Trol' water feed system. If you do, it is the air charge in the tank that determines the pressure that the system will fill to when cold.
Before instruction on how to re-charge the expansion tank (which you must do), we need to know if you have the above mentioned Fill-Trol system, or the conventional type with a separate pressure regulator.
Can you take digi pics of the system? If so, free account at Image hosting, free photo sharing & video sharing at Photobucket / upload pics there, drop a link here for us to view.
You may have what is called a 'Fill-Trol' water feed system. If you do, it is the air charge in the tank that determines the pressure that the system will fill to when cold.
Before instruction on how to re-charge the expansion tank (which you must do), we need to know if you have the above mentioned Fill-Trol system, or the conventional type with a separate pressure regulator.
Can you take digi pics of the system? If so, free account at Image hosting, free photo sharing & video sharing at Photobucket / upload pics there, drop a link here for us to view.
#5
09-17-10, 05:59 AM
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Thanks Guys,
The pressure today, cold, is sitting at about 7psi.
I have the EXTROL expansion tank, which I believe is similar to the Fil-Trol without the Fil?
Suggestions?
Thanks Again,
Bryan
The pressure today, cold, is sitting at about 7psi.
I have the EXTROL expansion tank, which I believe is similar to the Fil-Trol without the Fil?
Suggestions?
Thanks Again,
Bryan
#7
09-17-10, 01:12 PM
The Fill-trol system is different in that it's the pressure in the expansion tank that determines the cold fill pressure on the system, that's why I wanted to make sure that you didn't have that, because the procedure is different.
Furd is of course correct that if the system doesn't maintain pressure, there is a leak. Leaks in heating systems can be very slow and may not be noticed for years. Sometimes they stop leaking for a long time, because the minerals in the water tend to plug the leaks to some extent. They often are not noticed because with the pipes hot, a slow leak will evaporate before it 'hits the floor'.
Here is a write-up that I did a while back, a procedure for recharging expansion tank.
=======================================
1. Shut off boiler and allow to cool to under 100°F.
2. Shut off water supply line to boiler.
3. Drain only enough water from the boiler drain to drop the system pressure to ZERO. Do NOT completely drain the system! Only drop the pressure to zero!
4. With an ACCURATE tire pressure gauge, check the air charge in the tank on the air valve opposite the end of the tank that's connected to the system. If ANY water comes out of the air valve, the bladder inside the tank is shot and the tank needs replaced. If no water comes out the air valve, and the pressure is less than 12-15 PSI, continue to step 5. If the pressure is OK, turn the water supply to the boiler back on and repressurize the system, turn the power back on to the boiler, no service is necessary.
5. Using a bicycle pump, or a small air compressor, add air to the tank until you have 15 PSI air charge.
6. Check the boiler pressure gauge again, and if it has risen off ZERO, drain some more water from the boiler drain until it is again at ZERO.
7. Check the air charge on the tank again. If it is below 15 PSI, add air to the tank until it is at 15 PSI.
8. Repeat steps 6 and 7 until the boiler stays at ZERO and the tank stays at 15 PSI. At this point, the tank is properly recharged and the water supply can be turned on to re-pressurize the system, turn the power on to boiler and return to service.
====================================
Furd is of course correct that if the system doesn't maintain pressure, there is a leak. Leaks in heating systems can be very slow and may not be noticed for years. Sometimes they stop leaking for a long time, because the minerals in the water tend to plug the leaks to some extent. They often are not noticed because with the pipes hot, a slow leak will evaporate before it 'hits the floor'.
Here is a write-up that I did a while back, a procedure for recharging expansion tank.
=======================================
1. Shut off boiler and allow to cool to under 100°F.
2. Shut off water supply line to boiler.
3. Drain only enough water from the boiler drain to drop the system pressure to ZERO. Do NOT completely drain the system! Only drop the pressure to zero!
4. With an ACCURATE tire pressure gauge, check the air charge in the tank on the air valve opposite the end of the tank that's connected to the system. If ANY water comes out of the air valve, the bladder inside the tank is shot and the tank needs replaced. If no water comes out the air valve, and the pressure is less than 12-15 PSI, continue to step 5. If the pressure is OK, turn the water supply to the boiler back on and repressurize the system, turn the power back on to the boiler, no service is necessary.
5. Using a bicycle pump, or a small air compressor, add air to the tank until you have 15 PSI air charge.
6. Check the boiler pressure gauge again, and if it has risen off ZERO, drain some more water from the boiler drain until it is again at ZERO.
7. Check the air charge on the tank again. If it is below 15 PSI, add air to the tank until it is at 15 PSI.
8. Repeat steps 6 and 7 until the boiler stays at ZERO and the tank stays at 15 PSI. At this point, the tank is properly recharged and the water supply can be turned on to re-pressurize the system, turn the power on to boiler and return to service.
====================================
#8
09-17-10, 04:16 PM
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Hey Guys,
I'd love to post some pics, but the camera is nowhere to be found... Me thinks the wife snatched it for her weekend trip to visit her gf's.
The system is pretty simple. 3 zone (B,1,2) with circulators on the cold side. The hot side heads out to a manoifold where the three zones branch off. The EXTROL is on the hot side just before the manifold. The water fill line has a back-flow preventer and then the auto fill (12-15 psi).
The pressure relief valve breaks at 30psi, and comes off the back of the furnace.
There are no zone control valves, just the circulators for each zone. The system is controlled by a TACO 3 zone relay system.
I've been keeping an eye on the pressure gauge and it has been steady at about 8psi for the day. I just fired up the basement zone and as the temp rose from 130 to 192 the pressure budged up to about 12.5psi...
The strange this is that when the system is cold, and I try to fill (increase pressure) with the manual lever on the auto fill the pressure does not budge but it sounds like water if flowing into the system... I must admit I don't keep it open for long as I'm affraid the relief valve is going to blow....
I'll try to measure the pressure on the EXTROL sunday night, as I will need to go purchase a tire gauge.
I'm heading into the woods with the dog to camp tomorrow and tomorrow night, so I wont' be able to address the above until I return. At least it is not cold out yet.
If in fact the EXTROL is bunk, it should be fairly easy to replace, no?
Thanks Guys,
Bryan
Oh, I'll try to get some photos later this weekend when the wife gets back from the gf's....
I'd love to post some pics, but the camera is nowhere to be found... Me thinks the wife snatched it for her weekend trip to visit her gf's.
The system is pretty simple. 3 zone (B,1,2) with circulators on the cold side. The hot side heads out to a manoifold where the three zones branch off. The EXTROL is on the hot side just before the manifold. The water fill line has a back-flow preventer and then the auto fill (12-15 psi).
The pressure relief valve breaks at 30psi, and comes off the back of the furnace.
There are no zone control valves, just the circulators for each zone. The system is controlled by a TACO 3 zone relay system.
I've been keeping an eye on the pressure gauge and it has been steady at about 8psi for the day. I just fired up the basement zone and as the temp rose from 130 to 192 the pressure budged up to about 12.5psi...
The strange this is that when the system is cold, and I try to fill (increase pressure) with the manual lever on the auto fill the pressure does not budge but it sounds like water if flowing into the system... I must admit I don't keep it open for long as I'm affraid the relief valve is going to blow....
I'll try to measure the pressure on the EXTROL sunday night, as I will need to go purchase a tire gauge.
I'm heading into the woods with the dog to camp tomorrow and tomorrow night, so I wont' be able to address the above until I return. At least it is not cold out yet.
If in fact the EXTROL is bunk, it should be fairly easy to replace, no?
Thanks Guys,
Bryan
Oh, I'll try to get some photos later this weekend when the wife gets back from the gf's....
#9
09-17-10, 04:24 PM
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One other quick question...
If the system is running with low pressure, will this affect the amount of heat that the radiators put out. That is, will low pressure cause the radiators not to get to their full heat potential or is it an all or nothing situation, where there will be NO heat if the system has too little pressure.
The reason I ask is that the radiators get hot, but never seem to pump out a lot of heat. I think it may be becaise the pipes leading up the walls to the radiators are old stainless?? and probably 1/2"... So they cant move a lot of water.
When the system was rebuilt the main loops in the basement were all changed the 3/4" but the branch lines to the radiators are the original pipe.
Again, pics would probably help.
If the system is running with low pressure, will this affect the amount of heat that the radiators put out. That is, will low pressure cause the radiators not to get to their full heat potential or is it an all or nothing situation, where there will be NO heat if the system has too little pressure.
The reason I ask is that the radiators get hot, but never seem to pump out a lot of heat. I think it may be becaise the pipes leading up the walls to the radiators are old stainless?? and probably 1/2"... So they cant move a lot of water.
When the system was rebuilt the main loops in the basement were all changed the 3/4" but the branch lines to the radiators are the original pipe.
Again, pics would probably help.
#10
09-17-10, 05:33 PM
Do you actually hear water running through the supply line and yet the boiler pressure does not climb any further? Air tanks whether full of water or air, correctly or even incorrectly, cannot alter the ability of the pressure to rise further. You on a well?, or city water with a water meter? When it does climb to 12.5 psi, will it hold there?, or leak back down in short order?
#11
09-17-10, 06:13 PM
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Yup, it sounds like water is flowing, albeit slowly, into the system. I am on city water with about 45-65 psi depending on where I read it.
One thing I should mention is that last year I noticed low pressure, I added water through the fill and after about a minute the pressure relief valve blew open and made a hot mess of the basement floor. I didnt see the gauge respond during this event. This makes me wonder if my gauge is faulty??? Maybe it has a periodic malfunction???
Where is the appropriate location to test the pressure with my external meter?
The system when hot and running for an hour tonight made its way up to 18psi. Now that its been off for a while, it reads 14.5 psi.
Again, I'm wondering if a low pressure condition would decrease the heat output in the second story? Even with low pressure, the circulator pumps should move water, no?
Last year the system took forever to heat the house and would struggle on the coldest of nights, though I suspect this may also be do to poor insulation....
One thing I should mention is that last year I noticed low pressure, I added water through the fill and after about a minute the pressure relief valve blew open and made a hot mess of the basement floor. I didnt see the gauge respond during this event. This makes me wonder if my gauge is faulty??? Maybe it has a periodic malfunction???
Where is the appropriate location to test the pressure with my external meter?
The system when hot and running for an hour tonight made its way up to 18psi. Now that its been off for a while, it reads 14.5 psi.
Again, I'm wondering if a low pressure condition would decrease the heat output in the second story? Even with low pressure, the circulator pumps should move water, no?
Last year the system took forever to heat the house and would struggle on the coldest of nights, though I suspect this may also be do to poor insulation....
#12
09-17-10, 06:14 PM
Low water pressure will affect the pump's ability to get the water above it.
Have you bled your radiators of all the air?
You should get your expansion tank situation solved before asking more questions. Do what NjTrooper suggests to find out if your tank is properly pressurized. If it isn't, get it that way. That will help troubleshoot your system.
Have you bled your radiators of all the air?
You should get your expansion tank situation solved before asking more questions. Do what NjTrooper suggests to find out if your tank is properly pressurized. If it isn't, get it that way. That will help troubleshoot your system.
#13
09-17-10, 06:32 PM
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Thats the plan. I will report back in a couple days with my findings...
Thanks for the help guys.
Thanks for the help guys.
#14
09-17-10, 07:07 PM
Originally Posted by bryankloos
Again, I'm wondering if a low pressure condition would decrease the heat output in the second story? Even with low pressure, the circulator pumps should move water, no?
Last year the system took forever to heat the house and would struggle on the coldest of nights, though I suspect this may also be do to poor insulation....
Last year the system took forever to heat the house and would struggle on the coldest of nights, though I suspect this may also be do to poor insulation....
BTW - to get technical, when the pressure then is about 12 psi at the boiler in the basment, it will be maybe just a couple psi at the top of the uppermost radiator. The exact figure can easily be calculated using the water column(that is the "w.c." you see for gas pressure data, and such) formula.
#15
09-18-10, 11:14 AM
I NEVER trust an old boiler gauge, and I rarely would trust a new one! You can make up a gauge that will screw onto any of the boiler drains. Open the drain with the gauge attached and read the pressure.
From your description of the relief valve blowing, I would strongly suspect that the garge is gaubage.
To expand on ecman's post a bit, you need 1 PSI to raise water 2.31 feet. Inversely, you need 0.432 PSI to raise water 1 foot.
So, if it's say 20 feet from the boiler to the highest piping in the system, you need 20 X .432 = 8.64 PSI... that's just to get the water up to the top. In ADDITION, you must have some residual pressure up there, so you have to ADD 3-4 PSI and doing that, you are at roughly 12-13 PSI.
Even if the height is not that much, the MINIMUM COLD pressure should be 12 PSI.
Taller buildings will need more pressure as required...
Remember that this pressure has NOTHING to do with the pump being able to pump the water up higher. In a CLOSED system, all the pump has to do is run the 'ferris wheel'. In other words, the pump is only moving water past itself. GRAVITY is pulling the water down...
In OPEN systems, such as a domestic water system, it is true that the pump needs to be sized for the the height, but this is NOT true in a closed system.
From your description of the relief valve blowing, I would strongly suspect that the garge is gaubage.
To expand on ecman's post a bit, you need 1 PSI to raise water 2.31 feet. Inversely, you need 0.432 PSI to raise water 1 foot.
So, if it's say 20 feet from the boiler to the highest piping in the system, you need 20 X .432 = 8.64 PSI... that's just to get the water up to the top. In ADDITION, you must have some residual pressure up there, so you have to ADD 3-4 PSI and doing that, you are at roughly 12-13 PSI.
Even if the height is not that much, the MINIMUM COLD pressure should be 12 PSI.
Taller buildings will need more pressure as required...
Remember that this pressure has NOTHING to do with the pump being able to pump the water up higher. In a CLOSED system, all the pump has to do is run the 'ferris wheel'. In other words, the pump is only moving water past itself. GRAVITY is pulling the water down...
In OPEN systems, such as a domestic water system, it is true that the pump needs to be sized for the the height, but this is NOT true in a closed system.
#17
09-18-10, 03:35 PM
Which?: The pressure needed to allow water to get from the basement to the 2nd floor?, or the little bit of extra pressure NJ mentioned about?
#18
09-18-10, 03:56 PM
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In most residential hot-water heating systems the primary purpose of having the system under pressure when cold is to raise the water level to the uppermost point of the system as has already been explained. The reasoning for the few psi additional pressure is two-fold. The first is to compensate for poorly calibrated pressure gauges and the second is to hold any air in suspension to avoid air binding. The higher the pressure the smaller the air bubbles and the less the chance for air binding.
In commercial hot-water heating systems they are often designed as a high temperature hot-water system and will run at temperatures that are in excess of the normal (atmospheric pressure) boiling point of water. I worked on a system that had a designed temperature of 315 degrees F. and we ran the pressure at 75 to 90 psi.
In commercial hot-water heating systems they are often designed as a high temperature hot-water system and will run at temperatures that are in excess of the normal (atmospheric pressure) boiling point of water. I worked on a system that had a designed temperature of 315 degrees F. and we ran the pressure at 75 to 90 psi.
#19
09-18-10, 04:22 PM
NJTroopers post seemed to indicate that the pump could pump the water around the system if it was 0 psi. After rereading ecman51`s post before it, it seems I misinterpreted Trooper's post.
#20
09-18-10, 04:34 PM
Probably your misinterpretation of NJ's second to last paragraph of his post? Although everything he said before would indicate at least 12 psi is needed. Furd gave an excellent technical answer to the whys.
#21
09-18-10, 05:09 PM
Yeah, I probably could have worded that a bit better...
The STATIC fill pressure of 12 PSI cold, or higher if dictated by system height, is what 'fills' the system.
The energy added to the water by the pump (the pump 'head') is what moves the water around the system.
It is true that if the system is not full, i.e. at least enough pressure to lift the water to the top, and/or has air bubbles, the pump will not be able to move the water around the system. BUT, the point I tried to make is that it isn't the pumps job to push the water to the top. That is the job of the static pressure in the system. The pump's ONLY job is to turn the ferris wheel.
I can think of one more related reason, or at least some additional comments on furd's post, for the extra few pounds of pressure... IF the system is not 'pumping away' from the PONPC (Point of No Pressure Change, i.e. the connection point of the expansion tank) when the pump runs it will SUBTRACT pressure from the system. This could have the effect of dropping the pressure at the highest points in the system to zero, or possibly even negative pressure. In extreme cases, this could even cause the hot water to flash to steam. At the least, it will make it much easier for bubbles to form, a point mentioned by furd in his last response.
This is perhaps the best argument for pumping away from the expansion tank. By doing so, the pump will ADD pressure to the system and any air in the flow will return to the boiler to be caught by the air removal devices.
Verschtenen?
The STATIC fill pressure of 12 PSI cold, or higher if dictated by system height, is what 'fills' the system.
The energy added to the water by the pump (the pump 'head') is what moves the water around the system.
It is true that if the system is not full, i.e. at least enough pressure to lift the water to the top, and/or has air bubbles, the pump will not be able to move the water around the system. BUT, the point I tried to make is that it isn't the pumps job to push the water to the top. That is the job of the static pressure in the system. The pump's ONLY job is to turn the ferris wheel.
I can think of one more related reason, or at least some additional comments on furd's post, for the extra few pounds of pressure... IF the system is not 'pumping away' from the PONPC (Point of No Pressure Change, i.e. the connection point of the expansion tank) when the pump runs it will SUBTRACT pressure from the system. This could have the effect of dropping the pressure at the highest points in the system to zero, or possibly even negative pressure. In extreme cases, this could even cause the hot water to flash to steam. At the least, it will make it much easier for bubbles to form, a point mentioned by furd in his last response.
This is perhaps the best argument for pumping away from the expansion tank. By doing so, the pump will ADD pressure to the system and any air in the flow will return to the boiler to be caught by the air removal devices.
Verschtenen?
#22
09-19-10, 07:33 AM
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Hey guys,
Here is the report.
Extrol Expansion tank: 14psi, no water coming out.
Bioler: Holding at 8psi for the past couple days cold.
When I try reading the pressure at ANY zone drain, I get a small movement of the needle, but not enough to register any real pressure (maybe 1-2 psi).
I tried again to read the pressure on my water line, and it was 50 psi on the same cheap home depot meter. I wonder if I need a better quality meter to read the pressure from the drain???
So, what next?
Should I go and try to drain the upstairs radiators to determine if they have pressure???
Thanks,
Bryan
Here is the report.
Extrol Expansion tank: 14psi, no water coming out.
Bioler: Holding at 8psi for the past couple days cold.
When I try reading the pressure at ANY zone drain, I get a small movement of the needle, but not enough to register any real pressure (maybe 1-2 psi).
I tried again to read the pressure on my water line, and it was 50 psi on the same cheap home depot meter. I wonder if I need a better quality meter to read the pressure from the drain???
So, what next?
Should I go and try to drain the upstairs radiators to determine if they have pressure???
Thanks,
Bryan
#23
09-19-10, 08:13 AM
Mornin' Bryan,
Just to be sure about the tank, I want to make sure that you understood and followed the instructions... that when you recharged the tank you had the boiler at ZERO pressure, because if you didn't, you won't have the correct air charge... it's important, so I want you to confirm that.
WAS THE TANK CHARGE LOW ?
About your Home Depot pressure gauge: What is the range on that gauge? 0-200 ? 0-300 ? If so, you can not trust the gauge at the bottom of the range. Typically a gauge's accuracy falls way off at the bottom of the range. Usually best toward the middle of the range. You really need a gauge that has a range of no more than say 0-50 PSI, and if you can find a 0-30 it's even better. The one that you got from HD you should be able to remove the gauge that it came with and hit a real plumbing supply (or swimming pool supply) and pick up a gauge better suited to the low pressure we work with.
No, don't drain any radiators... You first need to know what the pressure REALLY is in the system. Then when it's cold, bring the system up to at least 12 PSI. Next, if there are bleeders on the radiators, let only the AIR out of them.
If you DO have low pressure in the system (and we don't know that you do yet) you will likely suck air IN to the system if you open bleeders at the top, and you don't want that.
Just to be sure about the tank, I want to make sure that you understood and followed the instructions... that when you recharged the tank you had the boiler at ZERO pressure, because if you didn't, you won't have the correct air charge... it's important, so I want you to confirm that.
WAS THE TANK CHARGE LOW ?
About your Home Depot pressure gauge: What is the range on that gauge? 0-200 ? 0-300 ? If so, you can not trust the gauge at the bottom of the range. Typically a gauge's accuracy falls way off at the bottom of the range. Usually best toward the middle of the range. You really need a gauge that has a range of no more than say 0-50 PSI, and if you can find a 0-30 it's even better. The one that you got from HD you should be able to remove the gauge that it came with and hit a real plumbing supply (or swimming pool supply) and pick up a gauge better suited to the low pressure we work with.
No, don't drain any radiators... You first need to know what the pressure REALLY is in the system. Then when it's cold, bring the system up to at least 12 PSI. Next, if there are bleeders on the radiators, let only the AIR out of them.
If you DO have low pressure in the system (and we don't know that you do yet) you will likely suck air IN to the system if you open bleeders at the top, and you don't want that.
#24
09-19-10, 08:23 AM
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I didn't drop the pressure in the system to 0psi, I simply measured the cahrge in the tank...
The gauge is 0-200, and yes, probably too beefy for the task at hand.
I'm thinking that I should get a proper pressure gauge and start from the beginning, then report back?
The gauge is 0-200, and yes, probably too beefy for the task at hand.
I'm thinking that I should get a proper pressure gauge and start from the beginning, then report back?
#25
09-19-10, 08:42 AM
OK, you need to follow the instructions. You will not get an accurate reading of the actual air charge in the tank if there is a different pressure on the other side...
Do that first, because if the expansion tank doesn't have the correct charge, all other bets are off the table.
Do that first, because if the expansion tank doesn't have the correct charge, all other bets are off the table.
#26
09-19-10, 09:34 AM
Originally Posted by NJ Trooper
I can think of one more related reason, or at least some additional comments on furd's post, for the extra few pounds of pressure... IF the system is not 'pumping away' from the PONPC (Point of No Pressure Change, i.e. the connection point of the expansion tank) when the pump runs it will SUBTRACT pressure from the system. This could have the effect of dropping the pressure at the highest points in the system to zero, or possibly even negative pressure. In extreme cases, this could even cause the hot water to flash to steam. At the least, it will make it much easier for bubbles to form, a point mentioned by furd in his last response.
This is perhaps the best argument for pumping away from the expansion tank. By doing so, the pump will ADD pressure to the system and any air in the flow will return to the boiler to be caught by the air removal devices.
Verschtenen?
This is perhaps the best argument for pumping away from the expansion tank. By doing so, the pump will ADD pressure to the system and any air in the flow will return to the boiler to be caught by the air removal devices.
Verschtenen?
#27
09-19-10, 10:16 AM
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Success, well, of sorts.
I pulled apart a pressure regulator and attached this gauge (0-50psi) to my adaptor. I then opened the system and let out a little water to try to drop to 0 psi. The funny thing is the pressure gauge didnt budge... It held at 8 psi, leading me to think the gauge is ****.
I then measured the pressure at the expansion tank, which read 0 psi. I pumped it up with my trusty bike bump to about 19 psi and then bled out a little air to give me just about 15-16psi. I then dropped the boiler pressure back to 0 psi and confirmed we were still at 15psi in the expansion tank.
After that, I opened up the water suply and gave it a little extra via the manual control for measure as I didn't hear much water flow into the system.
I measured the boiler pressure at the drain again and had 24 psi. So I bled a coulpe psi via opening another drain and brought the system to 15 psi.
I hope I didn't mess anything up by draining the pressure to 15 psi from 24....
That said, what next?
I pulled apart a pressure regulator and attached this gauge (0-50psi) to my adaptor. I then opened the system and let out a little water to try to drop to 0 psi. The funny thing is the pressure gauge didnt budge... It held at 8 psi, leading me to think the gauge is ****.
I then measured the pressure at the expansion tank, which read 0 psi. I pumped it up with my trusty bike bump to about 19 psi and then bled out a little air to give me just about 15-16psi. I then dropped the boiler pressure back to 0 psi and confirmed we were still at 15psi in the expansion tank.
After that, I opened up the water suply and gave it a little extra via the manual control for measure as I didn't hear much water flow into the system.
I measured the boiler pressure at the drain again and had 24 psi. So I bled a coulpe psi via opening another drain and brought the system to 15 psi.
I hope I didn't mess anything up by draining the pressure to 15 psi from 24....
That said, what next?
#28
09-19-10, 10:37 AM
ecman, I agree that a diagram would be very helpful, and last night I actually started working on one... but it's easier said than done... I sometimes (OFTEN) find it hard to keep things simple!
Bryan, OK, sounds good so far. No, you didn't mess anything up by dropping back to 15 from 24.
In fact, you could have probably left it at 24 for now, because the next step is going to be to find the bleeders on the rads, and go to each one and bleed any air off. When you do that, the pressure in the boiler will of course drop down again.
If your automatic regulator is working and filling the system to 12-15 PSI, you could just leave the water valve open as you are doing the bleeding. This way, you won't have to run up and down the stairs, bleeding and re-pressurizing the boiler.
Bryan, OK, sounds good so far. No, you didn't mess anything up by dropping back to 15 from 24.
In fact, you could have probably left it at 24 for now, because the next step is going to be to find the bleeders on the rads, and go to each one and bleed any air off. When you do that, the pressure in the boiler will of course drop down again.
If your automatic regulator is working and filling the system to 12-15 PSI, you could just leave the water valve open as you are doing the bleeding. This way, you won't have to run up and down the stairs, bleeding and re-pressurizing the boiler.
#29
10-03-10, 03:55 PM
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Hello Again,
Sorry to abandon my thread... the weather was a bit warmer here in New England the past couple weeks.
With the mercury dropping again lately, I'm back on the heating system.
I just bled all the rads, and fortunately there was very little air in any of the rads. The pressure in the system, as measures via the first floor zone drain is steady at about 21psi. It dropped a to 20psi dring the bleeding.
Now my question is where to set the aquastat?
The high side is currently set at 190F. I don't see a lower limit setting, but the burner temp gauge always sits at about 120, so I'm going to assume that is what the low setting is.
As a bit of backgroung, I have in-wall radiators in all the rooms. They have fins on them, and are all about 3 feet wide. A couple rooms in the house that have been updated now have baseboard rads installed. A couple rooms have 2 in-wall rads, on opposite ends of the room.
I've noticed that when the system is running in full glory, the rads don't seem to put out a ton of heat.
Suggestions?
Thanks,
Bryan
Sorry to abandon my thread... the weather was a bit warmer here in New England the past couple weeks.
With the mercury dropping again lately, I'm back on the heating system.
I just bled all the rads, and fortunately there was very little air in any of the rads. The pressure in the system, as measures via the first floor zone drain is steady at about 21psi. It dropped a to 20psi dring the bleeding.
Now my question is where to set the aquastat?
The high side is currently set at 190F. I don't see a lower limit setting, but the burner temp gauge always sits at about 120, so I'm going to assume that is what the low setting is.
As a bit of backgroung, I have in-wall radiators in all the rooms. They have fins on them, and are all about 3 feet wide. A couple rooms in the house that have been updated now have baseboard rads installed. A couple rooms have 2 in-wall rads, on opposite ends of the room.
I've noticed that when the system is running in full glory, the rads don't seem to put out a ton of heat.
Suggestions?
Thanks,
Bryan
#30
10-19-10, 06:12 AM
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Hey Guys,
I am going to start cleaning out the convectors this week. They are full of dust and other debris, which I suspect with the help of your suggestions is leading their decreased heat output.
I am going to snap a few photos of the before and after for you all to see. I'm not looking forward to this job!
With respect to the aquastat, I think it may be set too high? I am reading between 170 and 195 while the burner is in opperation. It seems the burner has no problem keeping the the water at the upper limit as it is cycling on and off fairly infrequently. My thoughts are that the dirty convectors can not distribute as many btu's as the burner is putting out... That said, do I need to adjust the aquastat or leave it where it is?
Photos soon....
Thanks,
Bryan
I am going to start cleaning out the convectors this week. They are full of dust and other debris, which I suspect with the help of your suggestions is leading their decreased heat output.
I am going to snap a few photos of the before and after for you all to see. I'm not looking forward to this job!
With respect to the aquastat, I think it may be set too high? I am reading between 170 and 195 while the burner is in opperation. It seems the burner has no problem keeping the the water at the upper limit as it is cycling on and off fairly infrequently. My thoughts are that the dirty convectors can not distribute as many btu's as the burner is putting out... That said, do I need to adjust the aquastat or leave it where it is?
Photos soon....
Thanks,
Bryan
#31
10-19-10, 11:43 AM
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Hey Guys,
Here are some pics of the burner, the monoflow T's, the compression connections to the old branch lines, and the convectors.
I cleaned out the surface crap in the convectors, and will try to either blow out or wash out the inter-fin dust and grime. Even with the covers off and the burner running these guys don't put out much heat... Maybe too skimpy? I wonder how many BTU's they are rated at???
Anyway, I'll try to clean them up some more and see if they throw any more heat.
Ironically, I found an acorn and some mouse crap in there.... Damn mice!!!
Here are some pics of the burner, the monoflow T's, the compression connections to the old branch lines, and the convectors.
I cleaned out the surface crap in the convectors, and will try to either blow out or wash out the inter-fin dust and grime. Even with the covers off and the burner running these guys don't put out much heat... Maybe too skimpy? I wonder how many BTU's they are rated at???
Anyway, I'll try to clean them up some more and see if they throw any more heat.
Ironically, I found an acorn and some mouse crap in there.... Damn mice!!!
#32
10-19-10, 03:36 PM
You should feel those pipes when the boilers is running to see if they are hot. I would think you have enough radiation. Older homes are usually way over radiated. You could also have an air blockage not allowing the water to flow.
#33
10-19-10, 07:18 PM
Yeah, I was wondering about that too droo, about how hot the pipes are... and even though not much air was reportedly bled out, I don't think I'm 100% confident that it is all out. Monoflo systems are a notorious PITA to get all the air out of.
But cleaning out Mickey and Minnie's acorn stash will help a lot!
BTW Bryan, as long as the fins are cleaned out, you will get way more heat out with the covers ON. Those covers need to be there in order that the 'chimney effect' pulls air THROUGH the element, rather than AROUND it.
I have that type of heat convector in my kitchen and bath, and they put out TONS of heat! (and they are also on monoflo tees) so I think once you get them cleaned, and are sure all the air is out, you will have plenty hot!
But cleaning out Mickey and Minnie's acorn stash will help a lot!
BTW Bryan, as long as the fins are cleaned out, you will get way more heat out with the covers ON. Those covers need to be there in order that the 'chimney effect' pulls air THROUGH the element, rather than AROUND it.
I have that type of heat convector in my kitchen and bath, and they put out TONS of heat! (and they are also on monoflo tees) so I think once you get them cleaned, and are sure all the air is out, you will have plenty hot!
#34
10-20-10, 12:10 PM
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Hey Guys,
I do think the system is free of air. The pipes leading to the convectors get HOT, and the convectors get rather hot as well.
I did notice an inprovement in the flow (though not great) through the convector after cleaning the fins. I managed to get the majority of crap out of them with a squirt bottle. I sprayed the fins and collected the dirty water beneath with paper towel.
I'm going to work on the onther convectors in the downstairs this afternoon and see how things go. I will also move a few things that are in front of the convectors to see iof I can get better air flow. Hopefully once they are all clean the convection currents in the rooms will move a bit faster and do the job.
Ao, how about that aquastat setting???
I do think the system is free of air. The pipes leading to the convectors get HOT, and the convectors get rather hot as well.
I did notice an inprovement in the flow (though not great) through the convector after cleaning the fins. I managed to get the majority of crap out of them with a squirt bottle. I sprayed the fins and collected the dirty water beneath with paper towel.
I'm going to work on the onther convectors in the downstairs this afternoon and see how things go. I will also move a few things that are in front of the convectors to see iof I can get better air flow. Hopefully once they are all clean the convection currents in the rooms will move a bit faster and do the job.
Ao, how about that aquastat setting???
#35
10-20-10, 01:30 PM
You might also consider air sealing around the convectors and their framing cavities. Foam, caulk, etc. Seal 'em up. In your pics, looks like lots of space for drafts, especially in an exterior wall. You can even foam around the supply/return penetrations.
Drafts in and around the cabinets will also compromise output.
Drafts in and around the cabinets will also compromise output.
#36
10-20-10, 04:00 PM
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Yes, spray foam and I get along
I'm planning on sealing up the cabs, as I have noticed some drafts around the rough openings for the cabs. I was thinking of spray-foaming the gaps and applying caulk where needed.
Also, the cab inserts seem to have a felt-ish gasket type material around the perimeter where the front cover makes contact. they have fallen apart and are worthless. Would it be wise to replace them with a weatherstripping of some sort?
I cleaned a few more cabs today, and the downstairs bathroom was actually feeling toasty! This is a good thing.
Heading away to a conference tomorrow, so the upstairs will have to wait until next week! hope the preggo wife can handle a few more cold nights
I'm just happy I am making forward progress and not stepping backwards.
Thanks Guys!
I'm planning on sealing up the cabs, as I have noticed some drafts around the rough openings for the cabs. I was thinking of spray-foaming the gaps and applying caulk where needed.
Also, the cab inserts seem to have a felt-ish gasket type material around the perimeter where the front cover makes contact. they have fallen apart and are worthless. Would it be wise to replace them with a weatherstripping of some sort?
I cleaned a few more cabs today, and the downstairs bathroom was actually feeling toasty! This is a good thing.
Heading away to a conference tomorrow, so the upstairs will have to wait until next week! hope the preggo wife can handle a few more cold nights
I'm just happy I am making forward progress and not stepping backwards.
Thanks Guys!
#37
10-20-10, 04:45 PM
Originally Posted by bryankloos
Also, the cab inserts seem to have a felt-ish gasket type material around the perimeter where the front cover makes contact. they have fallen apart and are worthless. Would it be wise to replace them with a weatherstripping of some sort?
Foam and caulk are many-splendored things.
#38
10-20-10, 05:07 PM
It is also very possible that replacing those strips will prevent 'dirt streaks' up the wall from air leaking around and out the back of the cover. You might look at something like the self-stick EPDM stuff at HD or Lowes... but I do wonder if the sticky stuff will stand up to the heat. There are also felt weather strip products you can buy...
By the way, I would turn the aquastat back to 180...
By the way, I would turn the aquastat back to 180...
#39
10-20-10, 06:07 PM
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180 it is!
It's a shame there's not a concrete way to measure the increase in output... Being a scientist, I try to steer away for subjective analysis. I guess if the wife is warm, that's good enough!
It's a shame there's not a concrete way to measure the increase in output... Being a scientist, I try to steer away for subjective analysis. I guess if the wife is warm, that's good enough!
#40
10-20-10, 07:32 PM
I'm sure there is a scientific method... but like you say, if the wife is warm... you don't have to listen to it!
While you are on yer knees cleaning... take a few minutes to straighten as many of those bent fins as you can. be careful! them fins is sharp!
While you are on yer knees cleaning... take a few minutes to straighten as many of those bent fins as you can. be careful! them fins is sharp!
