Pressure Too High

Hollyfeld · Post by **Hollyfeld** » Wed. Feb. 11, 2009 6:13 pm

Over the few weeks, I've noticed the pressure in the boiler increasing. When I first installed it the pressure was around the normal 17psi (thats what the oil one was usually at). So far I've witnessed it at 20 and then getting close to 25. I've manually blown the release valve into a bucket and the pressure drops, but continues to climb over many hours. **edit** Monday the pressure vent automatically blew into the bucket while I was at work. I've been manually venting when im home until I had time to change the pressure regulating valve, which was this evening.

I've changed the expansion tank because it was full of water and very heavy. This did not solve the problem.

I just changed the pressure regulating valve this evening and the pressure is getting very close to 25 within 2 hours. So again this did not solve the problem.

Why is this happening and what should I do next?

The aquastat is set at 160/180. The temp in the boiler is 180. No zones called for heat today.

crazy4coal · Post by **crazy4coal** » Wed. Feb. 11, 2009 6:21 pm

Does your unit have a DHW coil in it? If it does shut off the water feed to it and see if the pressure rise stops. If it stops the coil has a hole in it.

efo141 · Post by **efo141** » Wed. Feb. 11, 2009 6:25 pm

How do you heat your DHW, is it a coil or a indirect water heater? If you do, you may have a pin hole in the coil slowly pushing the pres. up in you boiler.

whistlenut · Post by **whistlenut** » Wed. Feb. 11, 2009 6:34 pm

How old is the domestic HW coil? Not much left to check. As previously stated, it must be a pinhole. Hope you have ball valves or valves that don't bypass even though fully closed. I happened to work on a boiler today that had 35 year old stop-N=wastes that were bypassing due to rotted rubber gaskets. Man I hate those valves. Ball valves or no valves....except for a nice gate. They usually don't leak.
I'd be finding out about a price of a new coil. If you have an indirect leaking, then you are in a very small minority.
Good luck, don't get burned!

Hollyfeld · Post by **Hollyfeld** » Wed. Feb. 11, 2009 7:07 pm

I heat the hot water with a Boilermate tank which is controlled with a zone valve.

Now that you mention a pin hole... about a week and a half ago I noticed the bath faucet upstairs was dripping. I replaced the entire unit in the wall and all the piping and bath accessories. This morning I noticed in the room directly below the shower the hot water pipe leading up to the bath was dripping at a an elbow. There is a lot of corrosion and limescale around this joint and I might have shaken it loose when messing with the pipe above. Its always been covered with pipe insulation, but I found where it was leaking. Could this cause the problem?

edit - How about a leak at the main shut-off for the water coming in. Its an old gate valve and its a little wet, although not really dripping as far as I can tell right now. I had to turn this off and on when I was doing the work upstairs. It's in the worst spot imaginable.

Tamecrow · Post by **Tamecrow** » Wed. Feb. 11, 2009 7:21 pm

Hollyfeld wrote:Why is this happening and what should I do next?

Could be the expansion tank is waterlogged or the pressure reducing valve is shot.

Terry

djackman · Post by **djackman** » Wed. Feb. 11, 2009 7:24 pm

Hollyfeld wrote: edit - How about a leak at the main shut-off for the water coming in. Its an old gate valve and its a little wet, although not really dripping as far as I can tell right now. I had to turn this off and on when I was doing the work upstairs. It's in the worst spot imaginable.

Find the curbstop valve - do you have a curbstop key or know someone who does?

Hollyfeld · Post by **Hollyfeld** » Wed. Feb. 11, 2009 7:29 pm

Tamecrow wrote:
Hollyfeld wrote:Why is this happening and what should I do next?
Could be the expansion tank is waterlogged or the pressure reducing valve is shot.

Terry

Tank was replaced last Thursday and the valve was replaced 3 hours ago.

djackman wrote:
Hollyfeld wrote: edit - How about a leak at the main shut-off for the water coming in. Its an old gate valve and its a little wet, although not really dripping as far as I can tell right now. I had to turn this off and on when I was doing the work upstairs. It's in the worst spot imaginable.
Find the curbstop valve - do you have a curbstop key or know someone who does?

I don't know where this valve is. I've never seen it, but I know the local community water company would know. The pressure coming into my house is about 30-35 psi. I test that this evening with a gauge from work on the hose bib just a few feet from the entry point. I'm going to test it again later.

Hollyfeld · Post by **Hollyfeld** » Wed. Feb. 11, 2009 7:31 pm

Even though the factory setting on the new pressure reducing valve is 12, I just turned it down 1 complete turn and then blew the pressure out of the boiler.

efo141 · Post by **efo141** » Wed. Feb. 11, 2009 7:32 pm

I have a friend that had 2 indirect water heaters fail in less than 10 years. He has hard water. I don't think the leak in the boiler mate(if thats the problem) has anything to do with your other plumbing leaks.You might want to get your water checked for hardness.

Hollyfeld · Post by **Hollyfeld** » Thu. Feb. 12, 2009 6:33 am

Pressure this morning was around 17psi. I'm still not convinced that a pressure reducing valve less than a year old failed, and a newly installed one wasn't set correctly at the factory. Something is fishy.

Matthaus · Post by **Matthaus** » Thu. Feb. 12, 2009 8:09 am

Measure the pressure on the input side of the auto fill valve, probably neither valve is bad, just need to adjust for high inlet pressure. The spring inside is supposed to regulate inlet pressure to 12psig out, if inlet pressure is high it might require backing off on the spring to compensate..
http://www.inspect-ny.com/heat/0861s.jpg
My city pressure is sometimes over 100psig, I had to back off the spring on the fill valve almost all the way to get 20psig at 190*F in the boiler, pressure starts out at 15psig with a cold boiler. Most houses have a regulator on the cold water supply near the water meter if high pressure is present, for some reason my house doesn't have that, one more thing to accomplish on the "get r done" list.

Hollyfeld · Post by **Hollyfeld** » Thu. Feb. 12, 2009 8:54 am

I measured the pressure coming into the house again this morning just to be sure and its right at 30-32psi. I could measure the pressure on the input side of the valve, but that would entail shutting down the boiler (again) just to remove the pipe connecting to the pressure reducing valve. The flue to the boiler goes directly over the valve with no room to do anything.

If neither valve was bad, then why didnt the pressure start to rise earlier than just a couple weeks ago?

Matthaus · Post by **Matthaus** » Thu. Feb. 12, 2009 12:30 pm

Hollyfeld wrote:I measured the pressure coming into the house again this morning just to be sure and its right at 30-32psi. I could measure the pressure on the input side of the valve, but that would entail shutting down the boiler (again) just to remove the pipe connecting to the pressure reducing valve. The flue to the boiler goes directly over the valve with no room to do anything.

I was off base then I guess, I agree two bad valves is not probable, I think something else must be going on... just not sure at this point.

Hollyfeld wrote:If neither valve was bad, then why didnt the pressure start to rise earlier than just a couple weeks ago?

Unless you are having fluctuations that you don't see.

CapeCoaler · Post by **CapeCoaler** » Thu. Feb. 12, 2009 1:04 pm

The pressure reducer is at fault.
Debris from the pipe is the probable cause.