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anaida
Hot water radiator are cold

I had changed the hot water pump and no more heat in any radiators. The heat goes back and forth to the boiler and pump, half way to the pipes and nothing else reaches the radiators. I have left them all open to exit air or water, nothing happend. I just have no idea why is that. Any help will be appreciated since it is cold in my house and I have a 6 months old baby.

brewster
Re: Hot water radiator are cold

Shouldn't be that hard to solve this----don't panic.

When you changed the pump, did you drain all water out of the entire system, or just drain the piping immediately around the pump??

Check the pressure reading on the boiler gauge ------the boiler pressure should read at least 12 psi.

Did you open the supply valve that allows additional fresh water into the boiler after you replaced the pump????? You have to open this valve to replace the water you lost when you partially drained the system & replaced the pump-----this will allow fresh water into the boiler so that you have approx 12-15 psi boiler pressure/altitude---this will drive the air out of the system when you open the bleed valves
at the radiators.

Do not exceed 30 psi pressure reading on the boiler gauge, or the pressure relief valve will open dumping water onto the basement floor.

Post back if you don't know where the supply valve is located.

Make sure you have re-opened all shut-off valves that were shut off when you replaced the pump---these are situated on the large mains near the boiler---circular handle valves have to be turned counter clockwise, lever handle valves have their lever pointing in line with the main piping when open.

Check that the arrow stamped on the housing of the new pump is pointing in the right direction (the same direction as the pump you removed), to make sure you didn't put the pump in backwards.

Check the electrical connections on the wires of the new pump & make sure you connected the wires properly so that the pump will operate & the boiler water will circulate when there is a call for heat.

Check to make sure the pump is operating when the boiler is running & there is a call for heat----touch the metal end of a large screwdriver onto the housing of the pump & place your ear on the plastic/wood handle---you should hear a high-pitched hum to verify that the pump is running.

Do you have zone valves on your system???

anaida
Re: Hot water radiator are cold

Hi, thanks so much for your expert answer, unfortunately, I have done everything what you said before the first posting and nothing happened. Since there is no pressure, and the water supply valve is on with no result, someone adviced me to fill the boiler with the tap water through the pipe I have unload the water before, tring to get some pressure. Did you ever hear about it?

brewster
Re: Hot water radiator are cold

anaida:

Not sure I understand your last post---are you saying you turned on the tap water valve to refill the boiler, but nothing happened and the boiler gauge is reading well below 12 psi, or near zero????

If this is the case, first try to open & close the tap water valve several times to see if you can get it working----if not, a SLIGHT tap with a hammer or other tool at the base of the valve sometimes gets it flowing again.

If you can't get the refill tap working, then yes, you can use the boiler drain valve at the bottom of the boiler (looks like a regular faucet) to refill the boiler with water by using a garden hose & various couplers to make a useable connection.

You would have to take a garden hose, & connect it to the outside tap, or other available tap, then take a six foot length of clothes dryer hose (having two female ends); connect one end to the male end of the garden hose, and the other end to the male end of the boiler drain valve.

Some garden hoses have female connections of both ends, or there are couplers available at HD/Lowe's to allow you to make the proper connection to the boiler drain.

Turn on the garden hose to full pressure, check for any minor leaks in the garden hose connections; tighten any connection leaks, then slowly open the boiler drain valve to allow tap water into the boiler until you reach 12-15 psi on the boiler gauge----do not exceed 20 psi in your filling procedure; keep a close eye on the boiler gauge needle & stop filling the boiler when you reach 15-20 on the boiler gauge dial.

Since the boiler drain is rarely used, lubricate the valve stem with a squirt of lubricating oil; some slight turning pressure with a wrench may be necessary to initially loosen the boiler valve handle, but be careful not to damage the boiler drain valve handle, which is fragile.

johnjh2o
Re: Hot water radiator are cold

What you have is a bad auto feed valve. It's not a good idea to use a hose to fill the boiler. Just have the auto feed replaced.

John

Rosaleeta
Re: Hot water radiator are cold
johnjh2o wrote:

What you have is a bad auto feed valve. It's not a good idea to use a hose to fill the boiler. Just have the auto feed replaced.

John

Hey John, don't be so high-and-mighty, unless you're volunteering to travel from the South East to make the repair yourself.

The house is cold, everybody's freezing, and the kid's got a bad cold!

Some people are so heartless.

johnjh2o
Re: Hot water radiator are cold
Rosaleeta wrote:

Hey John, don't be so high-and-mighty, unless you're volunteering to travel from the South East to make the repair yourself.

The house is cold, everybody's freezing, and the kid's got a bad cold!

Some people are so heartless.

Who is being heartless? All I'm doing is trying to help the OP out. If he should allow the pressure to get to high feeding the boiler by bypassing the regulator he could create a dangerous situation.

John

JLMCDANIEL
Re: Hot water radiator are cold
Rosaleeta wrote:

Hey John, don't be so high-and-mighty, unless you're volunteering to travel from the South East to make the repair yourself.

The house is cold, everybody's freezing, and the kid's got a bad cold!

Some people are so heartless.

Rosaleeta, saftey is always a primary concern for professionals, your remarks are unwaranted. Boilers can explode and it is never good advice to bypass a saftey feature.

Trying to fill with tap water won't even come close unless you feed the tap water into the highest point in the system and then you will still not have the right cold pressure.

Jack

johnjh2o
Re: Hot water radiator are cold
JLMCDANIEL wrote:

Rosaleeta, saftey is always a primary concern for professionals, your remarks are unwaranted. Boilers can explode and it is never good advice to bypass a saftey feature.

Trying to fill with tap water won't even come close unless you feed the tap water into the highest point in the system and then you will still not have the right cold pressure.

Jack

Thanks Jack. I was going to get nasty but decided against it.

John

JLMCDANIEL
Re: Hot water radiator are cold
johnjh2o wrote:

Thanks Jack. I was going to get nasty but decided against it.

John

Please don't, I have been checking Rosaleeta's other posts and if such confrontational posts continues I may ban the user.

Jack

anaida
Re: Hot water radiator are cold

Hi everyone,
Thanks for your consideration. I have already filled the radiators through the garden hose, before reading all these threds. It was fine last night, all radiators were hot and everybody happy. But next morning, there were "0" PSi, and one of the basebord radiators from basement , was licking through the valve when I have closed it. Of course,this is not the major problem. My question is: why the pressure is "0"?? Since I didn't have problems for ten years with the system, all of sudden I had to learn new things. Maybe this is how should be, maybe, I have to increase the termostat temperature to have the pump working and increase the pressure, which, I did, and still the pressure is "0". Thank you all for your advice.

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