getting air out
#1
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getting air out
what is the proper procedure for bleeding the air out of my system since i dont have air vents at the convectors. system on or off. ball vaves open or closed on which side of circulator do i somehow isolate a zone from another? etc etc Also, how do i go about getting the right size air valves for my convectors, i can figure out what size threads but do some vents release more air than others?
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first off down on the boiler do you have a RED painted assembly for the water into the boiler with a metal tag hanging on the adjusting screw stamped with 12LBS.that is your automatic water feed as you bleed the air out of the system.those convectors do they have small plugs that can be removed and vents installed?might be 1/4" or 3/8" threads standard at Home Depot.the system shold be off when you vent the air usually from the upper most convectors first then below floors one vent on each level will bleed the air don't need one on each convector(unless your talking old fashion radiators)question is how did the air get into the system.
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well the heating system was never 100% since the install. it was a complete overhaul. steam boiler converted for hot water all new pipes... everything new. contractor was in and out of the house for almost a year and when i finally got in the house the lowest floor, the basement didn't heat at all. the closest rad was warm the furthest one cold. also the top floors would heat even when heat was not called for. i called someone other than the original plumber, installer b/c the contractor and the plumber had a fall out and i had no way of reaching him directly. the guys who came in swore it was air in the system. they attached a hose to the valves by the pumps and let a lot of water out. it didnt really help. then i did some research on line and determined that the reason i had the heat upstairs even when it was not callled for was something called gravity feed or something like that so i hjad someone install a taco universal flockeck on each zone . that solved the second issue. now for sometime everything on the two top floors heated well but when the really cold weather started about a week ago i couldnt get the stats to rwead anything more that 68 to 71 at best on any floor. coincidence or not im not sure. now even on relatively ild days i cant get enough heat. also even when i try to set a thermostat up to the max setting of 90+ THE MOST I GET FROM THE BEST ZONE IS 74. NOW, THERE ARE NO AIR VENTS ON ANY of my rads so im guessing that could be the problem. i need some help .
#6
Pete, looking at your pressure and temp gauges I have to think that you may not have enough pressure in the system... and the temp seems a tad on the high side ...
I would think that at close to 200° you would be over 20 PSI... right now it looks to be barely above 15 ... and 15 is more like what a COLD system would read.
If you let the system go cold, what kind of pressure readings would you be getting? Say at 100° or less?
What is the total height of the heating system from the lowest point to the tip-top of the highest rad/baseboard?
I would think that at close to 200° you would be over 20 PSI... right now it looks to be barely above 15 ... and 15 is more like what a COLD system would read.
If you let the system go cold, what kind of pressure readings would you be getting? Say at 100° or less?
What is the total height of the heating system from the lowest point to the tip-top of the highest rad/baseboard?
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it is a 3 story private house. i have about 10' ceilings. how do i let the system go cold? to add pressure do i add water? the plumber had an air vent of sorts connected to the top of the expansion tank and the valve was tight i loosened it and got a little but not a lot of air out. i check it periodically and it seems to release air regularly now and maybe even a tad bit of water droplets. is this normal? i think since i loosened it that the heat might b working a little better?!?
also, should i install air vents to all rads/convectors i have none now. what kind/brand/make/size should i use. it looks like the plugs on the convectors is 1/2". does it matter what side i install one supply vs return?
thanks for any and all assistance
also, should i install air vents to all rads/convectors i have none now. what kind/brand/make/size should i use. it looks like the plugs on the convectors is 1/2". does it matter what side i install one supply vs return?
thanks for any and all assistance
#8
Pete... a three story house with ten foot ceilings needs a WHOLE lot more pressure than you are currently running! That right there is a HUGE part of your problem, perhaps ALL of it ...
You need 0.433 PSI per foot of height!
Boiler in basement? with 3 stories above? that's probably almost 40 feet from the bottom of the boiler to the top of the highest radiator, right?
You probably need more like TWENTY POUNDS COLD on that system! AND, with 20 PSI cold, you better have a properly sized expansion tank, because when the system heats up you don't want the pressure to rise more than say 5 PSI ... or you'll be blowing the relief valve all the time ... you might have to oversize the expansion tank because of that ...
You need 0.433 PSI per foot of height!
Boiler in basement? with 3 stories above? that's probably almost 40 feet from the bottom of the boiler to the top of the highest radiator, right?
You probably need more like TWENTY POUNDS COLD on that system! AND, with 20 PSI cold, you better have a properly sized expansion tank, because when the system heats up you don't want the pressure to rise more than say 5 PSI ... or you'll be blowing the relief valve all the time ... you might have to oversize the expansion tank because of that ...
#9
To let the system get cold, TURN IT OFF and wait! When the boiler temp gets down to like 100 or less, read the pressure and tell us what it is ... I bet it's gonna be less than 10 ... WAY TOO LOW for that height home!
Yes, adding water will raise the pressure, but there should be an automatic valve that adds water for you... it's probably set too low though, and I'm betting that the manual feed valve is closed.
The cap on the air vent should be loose all the time... you wanna let it do it's job, and it can't do that with the cap closed. That is an AUTOMATIC vent... you don't have to do anything for it to work. There's a float inside that lowers and releases the air all by it's lonesome... some water is normal when you hold that valve open ... a lot of water is normal if you continue to hold it open, but you'll burn your finger on the hot water!
just let it work on it's own...
Air bleeds on the radiators/convectors is a good idea... don't use the automatic variety though... the do eventually leak, and that could go unnoticed inside a cabinet ... use the small manual type that work with a coin or a 'clock key' ... you may need to use bushings if your holes are tapped at 1/2" because most of the bleeders are 1/8" thread ...
Yes, adding water will raise the pressure, but there should be an automatic valve that adds water for you... it's probably set too low though, and I'm betting that the manual feed valve is closed.
The cap on the air vent should be loose all the time... you wanna let it do it's job, and it can't do that with the cap closed. That is an AUTOMATIC vent... you don't have to do anything for it to work. There's a float inside that lowers and releases the air all by it's lonesome... some water is normal when you hold that valve open ... a lot of water is normal if you continue to hold it open, but you'll burn your finger on the hot water!

Air bleeds on the radiators/convectors is a good idea... don't use the automatic variety though... the do eventually leak, and that could go unnoticed inside a cabinet ... use the small manual type that work with a coin or a 'clock key' ... you may need to use bushings if your holes are tapped at 1/2" because most of the bleeders are 1/8" thread ...
#10
Pete, I just looked at your pics again, and you've got a '30' size expansion tank on there... I'm willing to bet that when you raise the pressure that that which is required for your home, you will either need a LARGER size '60' tank, or TWO size '30's...
In the one pic where you titled "not sure what this is or does" ... that is your PRESSURE REDUCING VALVE and that is where the pressure from your city water is reduced to the operating pressure for the boiler system ... is there a manual hand valve somewhere on that 1/2" pipe ?
In the one pic where you titled "not sure what this is or does" ... that is your PRESSURE REDUCING VALVE and that is where the pressure from your city water is reduced to the operating pressure for the boiler system ... is there a manual hand valve somewhere on that 1/2" pipe ?
#11
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the top of the highest rad is 24' from the ground because i have a total of three floors including the basement. the basement ceilings are 8' the top two floors are about 10' each so, how is the pressure using those numbers, i think i mislead you before into thinking that i had a total of 4 floors.
what does the automatic water feed look like?
there is a manual valve near the pressure reducing valve that i have used on occaSSION TO ADD WATER TO THE SYSTEM AFTER BLEEDING FROM THE VALVES NEAR THE CIRCULATORS.
i have added pictures to my photobucket containing pics of the rads/convectors, they look like 1/2" dont they. look at that one that has been piped from above....i wont be able to put an air vent on that one right??? b/c the threads for the vent are on the underside.
Pictures by djpetedagreek - Photobucket
can you reccomend a brand of manual air vents?
NJ Trooper thanks for all your help!!!
what does the automatic water feed look like?
there is a manual valve near the pressure reducing valve that i have used on occaSSION TO ADD WATER TO THE SYSTEM AFTER BLEEDING FROM THE VALVES NEAR THE CIRCULATORS.
i have added pictures to my photobucket containing pics of the rads/convectors, they look like 1/2" dont they. look at that one that has been piped from above....i wont be able to put an air vent on that one right??? b/c the threads for the vent are on the underside.
Pictures by djpetedagreek - Photobucket
can you reccomend a brand of manual air vents?
NJ Trooper thanks for all your help!!!
#12
the top of the highest rad is 24' from the ground because i have a total of three floors including the basement. the basement ceilings are 8' the top two floors are about 10' each so, how is the pressure using those numbers, i think i mislead you before into thinking that i had a total of 4 floors.
(28 X 0.433) + 4 = appx 16 PSI
Your system should be pressurized to 16 PSI when it is COLD. The pressure will increase when it's hot, but should probably not go up more than 8 PSI or so... The expansion tank you have may be sufficient...
what does the automatic water feed look like?

The tan bell shaped thingy with the lever on top is the "Pressure Reducing Valve" which drops your domestic water pressure to the required COLD fill pressure of your system.
In the upper right hand of that picture, there are two yellow handle ball valves.
The one at the top, on the horizontal section of pipe, with it's handle shown in the CLOSED position, is called a FAST FILL BYPASS. If you open that one (always do that SLOWLY!) you will get full domestic water pressure into the system. That valve can be used in combination with a hose and other valves to fill the system after draining for maintenance work, or for purging air if that's needed. It can also be used (open SLOWLY and WATCH the gauge!) to add water to the system.
The one that's hiding behind that other pipe, in the vertical secton of pipe, shown in the OPEN position is a manual feedwater shutoff valve. Closing that one would shut off ALL water supply to the boiler.
The fact that that one IS open, and your pressure is apparently LOW, means one of two things... either the Pressure Reducing Valve is clogged up with 'crud', and not passing any water through, or that reducing valve is adjusted too low.
i wont be able to put an air vent on that one right?

photo courtesy Bell & Gossett
This is the type you want to use. Avoid the 'automatic' variety as they can and do leak... you should be able to find this or similar at home centers and hardware stores. Yes, those plugs in your convectors do appear to be 1/2" thread... so you would need a 'bushing' to drop down to the 1/8" thread on this type air vent.
Normally these would be installed on the DOWNSTREAM end of the radiator, and bled with the circulator RUNNING... but some of yours appear a bit 'caddy wompus' and in that case I would install them on the higher of the two ends and bleed with the circulator NOT running...
You could also install these on top of a 6" pipe nipple with a coupling on top to reduce to 1/8" thread... air in the system would tend to collect in that pipe nipple until vented.
#14
They can be cleaned... but the best thing is probably just to replace it if it's really gunked up ... unfortunately you don't have a valve between the boiler system and the valve so you can't isolate it to work on it without draining the boiler, at least partially. So, until the spring anyway, just add some water with the top yellow handle valve until you get the pressure up to where it needs to be... then in the spring repair or replace the valve, and install another valve AFTER it so in the future you can do repairs on it without having to drain anything.
However, it's possible that it simply needs to be adjusted.
Do you want to try that first?
However, it's possible that it simply needs to be adjusted.
Do you want to try that first?
#16
Turn the boiler off and allow it to cool to 100°F or less.
That gadget with the lever on top of the reducing valve unscrews. Take it off.
You will see the top of a hollow threaded tube with 'coin slots' to turn the threaded tube.
There is a small metal rod inside that tube, carefully lift it out and put it aside, and DON'T LOSE IT!
There is a NUT on that tube that locks it in position, loosen that nut.
While watching the pressure gauge, turn the threaded tube ONE TURN CLOCKWISE and STOP AND WAIT a few minutes. These valves are sometimes slow to react. You should see the pressure increase on the gauge. If it does not increase, turn ONE MORE TURN clockwise. Keep track of how much you turn the tube! If the pressure STILL does not increase, try ONE MORE TURN... if it STILL does not increase, STOP... the valve is likely plugged. Return the setting to the original setting and snug (don't MUSCLE) the nut to hold the position. Replace the rod and lever cap.
If the pressure DOES increase, continue turning clockwise until you have 16-17 PSI on the gauges. Snug the lock nut, replace the rod and the lever cap.
This should be enough pressure for your system to operate properly, and allow you to bleed the air out. With the extra pressure, you may not have to do much bleeding, the air may be removed by the scoop and automatic vent, if not, then you will have to bleed some.
Watch the pressure gauge as the boiler heats up. With the extra pressure in the system, you may see it heading toward 25 PSI when hot. 25 is OK, but if it goes OVER that, you need to have a look at your expansion tank for correct air charge, and proper sizing.
That gadget with the lever on top of the reducing valve unscrews. Take it off.
You will see the top of a hollow threaded tube with 'coin slots' to turn the threaded tube.
There is a small metal rod inside that tube, carefully lift it out and put it aside, and DON'T LOSE IT!
There is a NUT on that tube that locks it in position, loosen that nut.
While watching the pressure gauge, turn the threaded tube ONE TURN CLOCKWISE and STOP AND WAIT a few minutes. These valves are sometimes slow to react. You should see the pressure increase on the gauge. If it does not increase, turn ONE MORE TURN clockwise. Keep track of how much you turn the tube! If the pressure STILL does not increase, try ONE MORE TURN... if it STILL does not increase, STOP... the valve is likely plugged. Return the setting to the original setting and snug (don't MUSCLE) the nut to hold the position. Replace the rod and lever cap.
If the pressure DOES increase, continue turning clockwise until you have 16-17 PSI on the gauges. Snug the lock nut, replace the rod and the lever cap.
This should be enough pressure for your system to operate properly, and allow you to bleed the air out. With the extra pressure, you may not have to do much bleeding, the air may be removed by the scoop and automatic vent, if not, then you will have to bleed some.
Watch the pressure gauge as the boiler heats up. With the extra pressure in the system, you may see it heading toward 25 PSI when hot. 25 is OK, but if it goes OVER that, you need to have a look at your expansion tank for correct air charge, and proper sizing.
#17
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Even if you are able to adjust the pressure, I would put on your list of springtime chores: replace the pressure reg valve (auto fill valve). From the looks of it, it's been around awhile.
NJ Trooper seems recognize it. But when you go to replace, personally, I would go with a Bell & Gossett.
Doug
NJ Trooper seems recognize it. But when you go to replace, personally, I would go with a Bell & Gossett.
Doug
#18
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There must be a valve, even if it's the main city-water shut-off, on the inlet side of the pressure reducer. Shut it. Then the pressure reducing valve is isolated - for replacement or disassembly.
My bill is in the mail.
Doug
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1 Weil Mclain boiler converted from steam to hot water running on natural gas. Model#: EG/PEG 45 (150,000 BTU/HR) also provides domestic hot water through coil less tank
3 zones – 3 Armstrong ASTRO-30 circulator pumps
1 Elbi diaphragm expansion tank Model#: XT-30
1 ARGO ARM-4P control with priority
3 TACO 218 universal flocheck
1 McDonell low water cutoff
1 Honeywell Auquastat relay type L8148E
3 LUX TX9000TS thermostats
Ball valves on both sides of each circulator pump and a drain valve
In Brooklyn, NY
Brick 3 story semi-attached home
Bedrooms on top floor
Living room, dining room, and kitchen on middle floor
Office, play area, boiler and bath on bottom floor – this floor is ground level at front of building and ½ below grade in back of building
Gas hot water heater added to system but only used during warm months when heat is not needed and boiler is shut down.
and the things you all named for me that i did not know what they were.
3 zones – 3 Armstrong ASTRO-30 circulator pumps
1 Elbi diaphragm expansion tank Model#: XT-30
1 ARGO ARM-4P control with priority
3 TACO 218 universal flocheck
1 McDonell low water cutoff
1 Honeywell Auquastat relay type L8148E
3 LUX TX9000TS thermostats
Ball valves on both sides of each circulator pump and a drain valve
In Brooklyn, NY
Brick 3 story semi-attached home
Bedrooms on top floor
Living room, dining room, and kitchen on middle floor
Office, play area, boiler and bath on bottom floor – this floor is ground level at front of building and ½ below grade in back of building
Gas hot water heater added to system but only used during warm months when heat is not needed and boiler is shut down.
and the things you all named for me that i did not know what they were.
#23
Pete, the Honeywell 8148E is your aquastat, and the high limit control in there should be set to 180...
but something puzzles me a bit... if you are running a 'tankless coil' in the boiler for domestic, you would typically have what they call a 'triple aquastat' which would keep the boiler warm for the purpose of producing domestic hot water. Since you have an auxiliary gas fired water heater, this is probably not an issue... your boiler probably stays hot enough during the winter to provide domestic water, and I assume that the gas fired unit will take up any 'slack'.
but something puzzles me a bit... if you are running a 'tankless coil' in the boiler for domestic, you would typically have what they call a 'triple aquastat' which would keep the boiler warm for the purpose of producing domestic hot water. Since you have an auxiliary gas fired water heater, this is probably not an issue... your boiler probably stays hot enough during the winter to provide domestic water, and I assume that the gas fired unit will take up any 'slack'.
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sorry it tok so long to get those photos of the area by the pressure reducing valve. but here they are.
Pictures by djpetedagreek - Photobucket
-how long should it take a zone to warm up from the time it is called to heat. from say 68degrees to 74 degrees?
Pictures by djpetedagreek - Photobucket
-how long should it take a zone to warm up from the time it is called to heat. from say 68degrees to 74 degrees?
#26
No problem Pete! got nothin' left BUT time! Gummint took everything else...
As I said, the yellow handle valve on the horizontal section of pipe is a FAST FILL BYPASS, and the normal position of that valve is CLOSED, as shown.
The one on the vertical section of pipe is your manual water feed shut off valve, and that would normally be OPEN, as shown.
The thing with the blue label is a BACKFLOW PREVENTER, and the pipe leading to the floor is a drain (obviously?) Under some conditions, the backflow preventer will open that drain and it will leak... normally this should not happen... it's usually because some debris gets under one of the valve seats.
How long to heat up? it DEPENDS... it always does... on so many things it's impossible to say... but I would GUESS that you might be able to get a 6° rise in like an hour or so? ? ?
Are you gonna let us know what happened when you increased the pressure? or keep us all in suspense... well, at least me anyway.
Status report please!
As I said, the yellow handle valve on the horizontal section of pipe is a FAST FILL BYPASS, and the normal position of that valve is CLOSED, as shown.
The one on the vertical section of pipe is your manual water feed shut off valve, and that would normally be OPEN, as shown.
The thing with the blue label is a BACKFLOW PREVENTER, and the pipe leading to the floor is a drain (obviously?) Under some conditions, the backflow preventer will open that drain and it will leak... normally this should not happen... it's usually because some debris gets under one of the valve seats.
How long to heat up? it DEPENDS... it always does... on so many things it's impossible to say... but I would GUESS that you might be able to get a 6° rise in like an hour or so? ? ?
Are you gonna let us know what happened when you increased the pressure? or keep us all in suspense... well, at least me anyway.
Status report please!