aquastat L8148E
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Hello People,
I need to replace the controller on my furnace. The system does not fire up.
The conroller I have reads: L8148e 1257.
However, I can not find this model anywhere.
Do you think I could use L8148e 1265 instead?
I appreciate your help,
Laszlo
I need to replace the controller on my furnace. The system does not fire up.
The conroller I have reads: L8148e 1257.
However, I can not find this model anywhere.
Do you think I could use L8148e 1265 instead?
I appreciate your help,
Laszlo
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#3
How did you determine that the aquastat was defective ?
Are you sure the damper is opening and the proving switch is 'making' ?
Personally, I'd want to be 100% sure before I plunked down a buck and a half on a new controller.
The first line of the ad that brew posted says this:
Honeywell L8148E1257 controller. Functional replacement for L8148E1265.
And these guys are about $30 cheaper:
8148E1265 at Patriot Supply
Are you sure the damper is opening and the proving switch is 'making' ?
Personally, I'd want to be 100% sure before I plunked down a buck and a half on a new controller.
The first line of the ad that brew posted says this:
Honeywell L8148E1257 controller. Functional replacement for L8148E1265.
And these guys are about $30 cheaper:
8148E1265 at Patriot Supply
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here is the timeline of what happend:
-first the circuit breaker tripped(I turned it back on)
-pushed on the switching relay and I saw the damper moving (I think it was opening)
-replaced the circulator pump (it had given high pitch whistling noise ocassionally. I had the plan how to replace it, I just never had the courage to do that before, I did not trust myself)
-still no luck, it did not fire up
-replaced the gas valve with exactly the same model, exactly the same way (I think only one wire connected the controller to the gas valve from B1 to TH, the other was just hanging there), Is it possible for the gas valve to work with only one wire connection?
-naturally no luck,
-tried to buy a controller but I ran out of time. The shops got closed by saturday noon
-started googling, found this forum:
-took out the controller and cleaned the contacts and put it back,
-tested different connections in the controller box
-realized that a wire connection was missing from B2(controller) to TR on the gas valve so I plugged it in and it WORKED! As soon as it fired up the new gas valve gives a constant buzzing noise when it is open, I hope it is natural.
some diagrams shows B2 to TH and B1 to TR some others
all the way around: B2 to TR and B1 to TH. Does it make any difference? I hope not.
I have 3 radiators two warmed up nicely. Now we can walk in the house without a coat and we are not confined to one room which was heated with an electrical heater.
The 3rd radiator is still cold I left the bleeder open and waiting for the water coming out. Out of the three radiators there is always one that takes a lot longer to warm up then the other two but sooner or later it usually warms up, as well:-)))
As you can see I went through a lot of hassle because of my inexperience.
Thank you so much for your help!!!!!!!!!!!!!
I learned a lot about my heating system in the last two days.
Pardon my writing style, as you see I am not a native speaker. I have just become an American Citizen on Friday.
God bless you all!
Thanks again,
Laszlo
-first the circuit breaker tripped(I turned it back on)
-pushed on the switching relay and I saw the damper moving (I think it was opening)
-replaced the circulator pump (it had given high pitch whistling noise ocassionally. I had the plan how to replace it, I just never had the courage to do that before, I did not trust myself)
-still no luck, it did not fire up
-replaced the gas valve with exactly the same model, exactly the same way (I think only one wire connected the controller to the gas valve from B1 to TH, the other was just hanging there), Is it possible for the gas valve to work with only one wire connection?
-naturally no luck,
-tried to buy a controller but I ran out of time. The shops got closed by saturday noon
-started googling, found this forum:
-took out the controller and cleaned the contacts and put it back,
-tested different connections in the controller box
-realized that a wire connection was missing from B2(controller) to TR on the gas valve so I plugged it in and it WORKED! As soon as it fired up the new gas valve gives a constant buzzing noise when it is open, I hope it is natural.
some diagrams shows B2 to TH and B1 to TR some others
all the way around: B2 to TR and B1 to TH. Does it make any difference? I hope not.
I have 3 radiators two warmed up nicely. Now we can walk in the house without a coat and we are not confined to one room which was heated with an electrical heater.
The 3rd radiator is still cold I left the bleeder open and waiting for the water coming out. Out of the three radiators there is always one that takes a lot longer to warm up then the other two but sooner or later it usually warms up, as well:-)))
As you can see I went through a lot of hassle because of my inexperience.
Thank you so much for your help!!!!!!!!!!!!!
I learned a lot about my heating system in the last two days.
Pardon my writing style, as you see I am not a native speaker. I have just become an American Citizen on Friday.
God bless you all!
Thanks again,
Laszlo
#5
Congratulations on your new citizenship! BRAVO and welcome to the USA !
Your writing style may be better than many born Americans I am sad to say.
You have it working, that is good.
I am concerned that you say that you have left the bleeder open. You should not have to wait for water to come out of that bleeder. There should (must) be pressure in the system at all times.
There is a gauge on the boiler to read the pressure and temperature. What is the pressure reading ? It should be between 12 and 15 PSI when the boiler is cold, and perhaps 5-8 PSI higher when it is hot.
Your writing style may be better than many born Americans I am sad to say.
You have it working, that is good.
I am concerned that you say that you have left the bleeder open. You should not have to wait for water to come out of that bleeder. There should (must) be pressure in the system at all times.
There is a gauge on the boiler to read the pressure and temperature. What is the pressure reading ? It should be between 12 and 15 PSI when the boiler is cold, and perhaps 5-8 PSI higher when it is hot.
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Unfortunately, the gauge doesn't work, it broke.
I will have to replace it or have it replaced if it is too difficult.
Is it difficult to replace it? (Crown boiler)
Is there a risk running the furnace without knowing the pressure?
The water pressure is high enough in the bathroom.
I don't understand why I don't have pressure in one radiator, maybe there is a blockage/dirt in the system?
I will have to replace it or have it replaced if it is too difficult.
Is it difficult to replace it? (Crown boiler)
Is there a risk running the furnace without knowing the pressure?
The water pressure is high enough in the bathroom.
I don't understand why I don't have pressure in one radiator, maybe there is a blockage/dirt in the system?
#7
You can find a gauge that you can use at Lowe's or Home Depot as a temporary installation. This is a gauge that is used for checking water pressure in a home, and is used by people who have lawn sprinkler systems in the yard. This gauge screws onto a hose connection. You can buy these for under $10 and screw it onto a boiler drain hose fitting. When you open the drain, you can read the boiler pressure. Do NOT leave the drain open all the time, only when you want to read the pressure.
Yes, there is. If you have very low pressure, you may not have enough water in the boiler (if you have a leak for an example). If this happens and you run the boiler with no water, you risk damaging the boiler and a very high risk of a fire starting. You also run a risk of high pressure, and if the safety pressure relief valve does not function, there could be a big explosion!
Is this third radiator at a higher level than the others ? If so, then it is very possible that you do not have enough pressure in your system. If it is at the same level, or lower than the others, you may have some type of blockage, or you may have a valve that is closed that should be open.
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Hello Trooper,
You were right the pressure is low and yes the third radiator is on the second floor. I don't use the second floor radiator all the time. I did not detect any leak where we would lose water but couple days ago the system was gurgling and the pressure relief valve on the furnace openned up and shot hot black water out. The whole basement got full of steam. I was not at home, my wife told me that. I bled the radiators again and it does not gurggle anymore. I keep an ear on the radiators now.
The furnace must have overheated. I wonder why the sensing bulb (on the controller) did not detect the high temperature and why it did not shut the furnace down?
I know that there is no heat conductive compound around the sensing bulb. Maybe it is the controller's fault.
The plumbing store does not sell the compound, maybe I can buy it online.
I will have to buy the thermo-pressure gauage online too because I could not find the exact model in the store.
How can I raise the system to the proper pressure?
How should I bleed the expansion tank?
Do you think I need to replace the air purger?
Thank you for your help,
Laszlo

http://users.adelphia.net/~lacilasazlo/gauge.htm
You were right the pressure is low and yes the third radiator is on the second floor. I don't use the second floor radiator all the time. I did not detect any leak where we would lose water but couple days ago the system was gurgling and the pressure relief valve on the furnace openned up and shot hot black water out. The whole basement got full of steam. I was not at home, my wife told me that. I bled the radiators again and it does not gurggle anymore. I keep an ear on the radiators now.
The furnace must have overheated. I wonder why the sensing bulb (on the controller) did not detect the high temperature and why it did not shut the furnace down?
I know that there is no heat conductive compound around the sensing bulb. Maybe it is the controller's fault.
The plumbing store does not sell the compound, maybe I can buy it online.
I will have to buy the thermo-pressure gauage online too because I could not find the exact model in the store.
How can I raise the system to the proper pressure?
How should I bleed the expansion tank?
Do you think I need to replace the air purger?
Thank you for your help,
Laszlo
http://users.adelphia.net/~lacilasazlo/gauge.htm
Last edited by laszlo; 12-02-07 at 09:04 AM. Reason: picture did not go through
#9
Hello Laszlo, I hope that your wife was not scared too badly when that happened !
I wish that those Watts gauges had a better resolution at the lower ranges. It is possible to remove the gauge itself from the hose fitting and install a 0-30 PSI gauge in it's place. It appears that you have around 10 PSI in the system and that is not enough...
The relief valve will open only if there is a PRESSURE increase, there is not a temperature sensing feature on those, so it is not likely that your aquastat is at fault this time.
Can you take pictures of the boiler and the expansion tank, and the pipes and valves around the boiler and post them ? It is very difficult to explain if we can not see the system. Please take at least one wide view of the whole system for reference.
I would recommend using the www.photobucket.com site for various reasons...
I wish that those Watts gauges had a better resolution at the lower ranges. It is possible to remove the gauge itself from the hose fitting and install a 0-30 PSI gauge in it's place. It appears that you have around 10 PSI in the system and that is not enough...
The relief valve will open only if there is a PRESSURE increase, there is not a temperature sensing feature on those, so it is not likely that your aquastat is at fault this time.
Can you take pictures of the boiler and the expansion tank, and the pipes and valves around the boiler and post them ? It is very difficult to explain if we can not see the system. Please take at least one wide view of the whole system for reference.
I would recommend using the www.photobucket.com site for various reasons...
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Laszlo
I too want to offer my congratulations on becoming an American citizen. God Bless the USA.
I doubt you will find the heat conductive compound sold separately & I've never seen a factory installed aquastat where the compound was used. It is unlikely the air purger, unless you mean the automatic air vent, would need to be replaced.
Some more pictures of the boiler & nearby piping would be helpful it explaining to you how to increase the pressure, etc. If you can find a pressure gauge with a lower scale
(30, 50, or even 100 pound max.) it would make reading the pressure easier. That gauge looks like it is 1/4" pipe thread. If you can provide a model number of the boiler, I might be able to tell you what size thread the factory boiler gauge uses.
I doubt you will find the heat conductive compound sold separately & I've never seen a factory installed aquastat where the compound was used. It is unlikely the air purger, unless you mean the automatic air vent, would need to be replaced.
Some more pictures of the boiler & nearby piping would be helpful it explaining to you how to increase the pressure, etc. If you can find a pressure gauge with a lower scale
(30, 50, or even 100 pound max.) it would make reading the pressure easier. That gauge looks like it is 1/4" pipe thread. If you can provide a model number of the boiler, I might be able to tell you what size thread the factory boiler gauge uses.
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getting ready for the winter
Hello Gents,
I uploaded some pictures to Photobucket as you advised.
I still try to solve the issues I mentioned above with the pressure and overheating, gurgling.
Last winter sometimes the pressure was so low that some of the radiators did not get hot or other times it became so high when the thermostat was turned up that the relief valve sprayed out black water. Some other times the system ran smooth.
Any idea what might causes these issues, what should I test?
Would you like to see more pictures from different angles?
Any advise greatly appreciated,
Laszlo
http://s380.photobucket.com/albums/oo250/lacilaszlo/
I uploaded some pictures to Photobucket as you advised.
I still try to solve the issues I mentioned above with the pressure and overheating, gurgling.
Last winter sometimes the pressure was so low that some of the radiators did not get hot or other times it became so high when the thermostat was turned up that the relief valve sprayed out black water. Some other times the system ran smooth.
Any idea what might causes these issues, what should I test?
Would you like to see more pictures from different angles?
Any advise greatly appreciated,
Laszlo
http://s380.photobucket.com/albums/oo250/lacilaszlo/
#12
Laszlo, good to hear from you again and sorry that you did not get the system operating properly by now.
I'm sorry that what I have to say may cause alarm to you.
Those pictures tell me some serious safety issues with that boiler, and some non-safety related issues that will prevent it from operating properly.
The most serious thing that I can see is the way that the pressure relief valve is piped. It appears that there is a 90° elbow on the end of it, and that elbow is pointing directly at the place where people (or God forbid, the child that uses that small bicycle) may be standing ... When the relief valve opens up and sprays 190°F water straight out sideways, if someone is there they can be EXTREMELY seriously injured, perhaps even KILLED.
That relief valve should be replaced immediately, and piped straight down to within 150mm of the floor. If it is still possible after doing this repair for someone to be sprayed by the water splasing up from the floor, a shield of some sort should be installed around it to prevent injury to people.
It does not look as though the automatic flue damper is in very good condition, and that can pose a SERIOUS problem with CARBON MONOXIDE in the home. CARBON MONOXIDE is a silent killer. It is an odorless gas. You will not know until it is too late.
PLEASE TELL ME THAT YOU HAVE FUNCTIONAL CARBON MONOXIDE DETECTORS IN EVERY BEDROOM AT THE VERY LEAST. I will sleep better at night knowing this, and if you don't have them, get them.
The next most obvious thing that I see wrong is not so much of a safety issue, but will NOT work properly as it is installed, and could cause pressure and circulation problems such as you are experiencing. The AIR SCOOP that the expansion tank is connected to will NEVER function in the vertical position that it is mounted. The automatic air vent will NEVER function properly the way it too is mounted. The AIR SCOOP must be mounted horizontally, and the VENT part must be mounted vertically.
It appears that there is some serious water leakage and corrosion of the pipes surrounding that area.
I am afraid.
I'm sorry that what I have to say may cause alarm to you.
Those pictures tell me some serious safety issues with that boiler, and some non-safety related issues that will prevent it from operating properly.
The most serious thing that I can see is the way that the pressure relief valve is piped. It appears that there is a 90° elbow on the end of it, and that elbow is pointing directly at the place where people (or God forbid, the child that uses that small bicycle) may be standing ... When the relief valve opens up and sprays 190°F water straight out sideways, if someone is there they can be EXTREMELY seriously injured, perhaps even KILLED.
That relief valve should be replaced immediately, and piped straight down to within 150mm of the floor. If it is still possible after doing this repair for someone to be sprayed by the water splasing up from the floor, a shield of some sort should be installed around it to prevent injury to people.
It does not look as though the automatic flue damper is in very good condition, and that can pose a SERIOUS problem with CARBON MONOXIDE in the home. CARBON MONOXIDE is a silent killer. It is an odorless gas. You will not know until it is too late.
PLEASE TELL ME THAT YOU HAVE FUNCTIONAL CARBON MONOXIDE DETECTORS IN EVERY BEDROOM AT THE VERY LEAST. I will sleep better at night knowing this, and if you don't have them, get them.
The next most obvious thing that I see wrong is not so much of a safety issue, but will NOT work properly as it is installed, and could cause pressure and circulation problems such as you are experiencing. The AIR SCOOP that the expansion tank is connected to will NEVER function in the vertical position that it is mounted. The automatic air vent will NEVER function properly the way it too is mounted. The AIR SCOOP must be mounted horizontally, and the VENT part must be mounted vertically.
It appears that there is some serious water leakage and corrosion of the pipes surrounding that area.
I am afraid.
Last edited by NJT; 09-29-08 at 08:42 PM.
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furnace condition
Thanks for the fast response Trooper.
I have a couple Carbon Monoxide detectors in the house.
I will make sure that I pipe down the relief valve before I fire up the furnace.
As far as the Air Scoop, it was installed by a "professional".
I paid quite a bit of money for the work he did.
I am thinking this coming Saturday I would redo the piping for the Air Scoop to place it in a horizontal position.
Do you think I could do the soldering with a hand tourch?
Is that the most likely cause for the pressure/ temperature inbalance?
Where would you start detecting the problem?
Thank you again,
Laszlo
I have a couple Carbon Monoxide detectors in the house.
I will make sure that I pipe down the relief valve before I fire up the furnace.
As far as the Air Scoop, it was installed by a "professional".
I paid quite a bit of money for the work he did.
I am thinking this coming Saturday I would redo the piping for the Air Scoop to place it in a horizontal position.
Do you think I could do the soldering with a hand tourch?
Is that the most likely cause for the pressure/ temperature inbalance?
Where would you start detecting the problem?
Thank you again,
Laszlo
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Hello,
I redid the piping for the air scoop/air vent.
It was a lot more work than I thought it would have been.
Now the water is coming/spraying out on the top the air vent(the little copper cylinder) when I fill up the system.
Any idea why?
Thank you,
Laszlo
I redid the piping for the air scoop/air vent.
It was a lot more work than I thought it would have been.
Now the water is coming/spraying out on the top the air vent(the little copper cylinder) when I fill up the system.
Any idea why?
Thank you,
Laszlo
#15
That little cylinder has a 'float' inside it. When the water lifts the float up, it closes the valve on the top. The valve is not sealing properly, most likely from small pieces of debris in the system having entered the device. They are fairly inexpensive and I would simply replace it. Home Depot or Lowes should carry them.
In the meantime, if you need heat, you can screw a tire cap on that valve tight, and stop the leak. But you may have air.
Sometimes if you push the valve stem by hand you can clear the valve and it will close...
In the meantime, if you need heat, you can screw a tire cap on that valve tight, and stop the leak. But you may have air.
Sometimes if you push the valve stem by hand you can clear the valve and it will close...
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still having problem
Today, I turned on the system.
I filled it up with water first. The second floor
radiator did not even got filled up probably because of the low pressure.
Then, I turned the gas on. The furnace just running and heating the water. The radiators got
hot on the first floor. I was on the second floor waiting for the water to come up. Finally it reached the second floor and filled up the radiator with hot water. That is when I turned off the bleeder on the second floor.
By that time the radiators on the first floor got very hot. I went down to the basement and saw as the air scoop was reliving the steam like a locomotive. That is when I turned the whole system off. It seems like there is nothing that would tell the furnace to stop heating the water and it just heats out of control. That is why my original idea was to replace the controller last year.
Where could I set the water temperature lower so it would not raise the water temp so high.
I see only one dial on the controller. Is that the one? What would you do?
Please help,
Laszlo
I filled it up with water first. The second floor
radiator did not even got filled up probably because of the low pressure.
Then, I turned the gas on. The furnace just running and heating the water. The radiators got
hot on the first floor. I was on the second floor waiting for the water to come up. Finally it reached the second floor and filled up the radiator with hot water. That is when I turned off the bleeder on the second floor.
By that time the radiators on the first floor got very hot. I went down to the basement and saw as the air scoop was reliving the steam like a locomotive. That is when I turned the whole system off. It seems like there is nothing that would tell the furnace to stop heating the water and it just heats out of control. That is why my original idea was to replace the controller last year.
Where could I set the water temperature lower so it would not raise the water temp so high.
I see only one dial on the controller. Is that the one? What would you do?
Please help,
Laszlo