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wlmpdiycr 10-19-2011 02:52 AM

pressure relief valve is leaking on boiler
3 Attachment(s)
Help Please!

Short version - pressure relief valve is leaking. Tried replacing leaking pressure valve with new APOLLO Value RVW30-F Safety Relief Valve and this valve leaked water from the top after we put it on and turned the water back on. So we put the old valve back on and it is constantly dripping water. We didn't turn the unit on because pressure relief valve is leaking. The pressure is at 19. What should we do? Tired of emptying water buckets!

Long version
In March the thermostat went out. We tried to replace it, but it still didn’t work. Did a few tested and figured out it was the aquastat acting up. Called a heating tech. He came out and said the aquastat needed replacing. He replaced it and the boiler worked! But the next day we weren’t really getting good heat. So we called tech and asked it aquastat needed adjusting? Tech told us it doesn’t but he would stop by. Tech looked at pipes and touched them and told us the system wasn’t balanced. He opened the screw on one big pipe, drained the expansion tank, and then bleed the radiators. We got fantastic heat. Two days later, we noticed water near the boiler, the pressure relief valve was leaking. We were about to turn boiler off when we saw the psi was 30, but we noticed the expansion tank was off. So now we need to replace the pressure relief valve because the heating tech wants to charge us again to put on the pressure relief valve after we purchase another one!
What is weird is the water leaking from the pressure relief valve. When we tried to replace valve, we turned off water to boiler, turned off fill valve, and expansion tank and we still got a good stream of water trickling from pressure relief valve. We know that you have to drain a little water out of boiler, but the water hasn’t stop?

Peerless Gas Boiler GEM-9958 series (1st picture)
The old pressure relief valve (2nd picture)
Apollo value RVW30-F (replacement pressure relief valve) (3rd picture)

Any advice is greatly appreciated!

oh'mike 10-19-2011 05:31 AM

An HVAC guy will help soon----However---most often when the pressure relief valve dribbles it is a symptom of an expansion tank failure----

Let's see what a boiler man has to say.

COLDIRON 10-19-2011 06:38 AM

Check your auto feed valve, it might be sticing open and not closing completely.

wlmpdiycr 10-19-2011 01:46 PM

Is there a way to check to see if auto feed valve is not working or the expansion tank ?

diyorpay 10-19-2011 02:43 PM

Flick it fast. In other words, with a bucket underneath, pull up tab and let it go, fast. Try a number of times. If any luck, it may adjust to normal.

beenthere 10-19-2011 03:33 PM

A. It looks like you have the old relief valve on wrong. looks like you have its discharge port piped to the boiler. Look at it, it should be marked which end is which.

wlmpdiycr 10-19-2011 03:50 PM

Is the relief valve on the second picture wrong? Its the new one we tried, but it leaked at the top when we put it on, so maybe its wrong?

beenthere 10-19-2011 04:29 PM

Yes, its connected that its discharge port is connected to the boiler.

wlmpdiycr 10-19-2011 05:21 PM

Is it normal to have water coming out of the pipe connected to the safety relief valve when you are trying to replace it?

we turned off water to boiler
turned off expansion tank
drained water from boiler until pressure read 0 PSI
then we put the new relief valve on wrong, but while putting it on water was coming out? Is that normal?

oh'mike 10-19-2011 05:52 PM

That would be normal--the boiler and pipes are holding water----so you are draining some from the system.

beenthere 10-19-2011 06:18 PM

Yep, its normal. Gotta be fast when changing them out.

biggles 10-19-2011 08:12 PM

is that a cold start boiler as in it doesn't maintain the water temp but heats when stat calls? when it starts the auto feed PSI should be just readable on the guage by the time the house reaches setpoint and shuts off you should be no where near 30PSI how many floors??..the relief is doing what it was designed where is that pressure coming from...flip the lever on the relief and let it flush if you need the heat running a dripping relief isn't a big thing to worry about just check the bucket but it should never flow and make up feed water...water has to expand when heated and if the EX tank isn't taking up the heated water it will show back on the boiler guage....and water will blup out of an isolated boiler when changing anything below the piping going up into the house...:wink:

wlmpdiycr 10-20-2011 03:05 AM

1 Attachment(s)
Yes, its a cold start boiler. We have 2 floors. We haven't heated boiler yet. Was waiting to get pressure relief valve on first before we turned boiler on.

Right now the PSI is 17. The water is on, the fill valve is on, but the expansion tank is closed. Today I will test to see if the fill valve is working. If the fill valve is okay, then we will put on pressure relief valve, the right way this time - like in picture below. If this goes well, then we will open expansion tank and turn on boiler.

Or should I bleed each radiator before turning on boiler to make sure no air is in system?

Are there any other thing I should do or test before I turn on boiler?

wlmpdiycr 10-20-2011 03:08 AM

Should I check setting on the aquastat to make sure its okay too?

beenthere 10-20-2011 04:12 AM

The 30 PSIG came from when the boiler ran with the valve to the expansion tank closed.

Cast iron rads, the aquastat can probably be set down to 160 if its not already set there or lower.

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