Furnace Always Building Pressure

ODDSNENDS4U wrote:Hi,
Something else I kept forgetting to mention. We seem to be not getting hot water all the time like we used to. The wife just reminded me after her shower that she ended her shower with warm water instead of hot like it used to be. Any thoughts?
Den

Well, in a normal electric HWH, warm water, not hot, would be an indication your TPR valve is defective, and its blowing all the hot water out. Change it out as soon as you can, even if its not the main cause of your High-pressure issue.

Pinholes in your water coil will bring down your water temp instead of cold water staying in the 1/2 copper finned coil
pipe /loop the cold water is leaking into the boiler water bringing down your DHW water temp and increasing your PSI on the boiler Replace with a new water coil 5 or 7 GMP.

Good Morning all,
Well I had the dhw feed valve closed all night and a spigot open in the bathroom above the boiler and there was still water in my bucket in the morning. Not as much as the night before but still some there. And this morning the pressure was at about 31. So now are we looking at the expansion tank? Any help ?
Den

Hey Coal berner, Why do you use Buckwheat instead of Rice coal?
Den

I think you said you have a ceiling hung tank. If you do, opening the drain valve is not enough to empty it. It gets airbound. You need to get a small hose, or something through the drain valve and up to the top of the tank to break the vacuum. Make sure the water is cold and expect a flood.

Some people never have a bit of trouble with ceiling hung tanks, but because the waterlogging, that's why I like the Extrol diaphragm tanks.

Somethings goofy.... water pressure can only come frome three places: Expanding water that has no place to go, The feed to the boiler or a leaky domestic coil. You say you shut off the boiler feed and it still made pressure...Then you shut off the domestic pressure and still made too much pressure, soooo, my best guess is either the boiler feed that isn't shutting tight, and a bad pressure reducer, or a expansion tank problem. On top of that I'd question the integrity of the pressure relief valve. I think I'd remove the expansion tank & test it. You need to remove all pressure from the system to do this unless there's a valve between the tank & system. (rarely is there one) Once it's removed put 12 pounds of air in the air valve. If it will not hold the air, the bladder has failed.

Hi,
There is no valve between the lines and the exp. tank. It just screws directly on a pipe nipple. Now What is the best way to drain the system down to take that off without a major flood. And yes it is a bladder type exp tank. A honeywell with a butyl bladder. Seems odd as it is only about 1 yr old. That is why I have been avoiding that avenue.
Den

ODDSNENDS4U wrote:Hi,
There is no valve between the lines and the exp. tank. It just screws directly on a pipe nipple.

Den, get a copper or brass cap the same dia as the pipe nipple the press tank is screwed into. I am assuming the nipple is MPT, so the cap should be FPT. Unscrew the press tank, and quickly screw the cap onto the end of the nipple. This will save most of your water, and now you can play with the press tank.
Or, what I would do, is take off the press tank and let the system drain down as much as it wants to. Then screw on a FPT ball valve to the end of the nipple, and this way you can always isolate the press tank in the future. Leave the ball valve in place, and just screw the press tank into the ballvalve. No sweating required.

Why not just turn off the water inlet valve, reduce the pressure in the boiler to zero and then use a bicycle valve gauge and see if the tank has 12# of pressure at the fitting on the round end? No tank removal required. If water comes out of the valve, you know the bladder is shot.

Hi,
Since it was an easy job, I tried as you said stoker-man. I released all the pressure and there was no pressure in the exp tank. No water came out either. I pumped it up to about 12#. Could this have been my problem. If so,where did the air pressure go that was in the exp. tank bladder?
Den

The air valve itself may be leaking.

ODDSNENDS4U wrote:Could this have been my problem.

Could be you found the problem. Did the valve have a metal cap on it? By dropping the pressure to zero you may have let air into the system if any air purges were not closed. If only a little it may take care of itself. If a lot you'll know when a zone won't heat. Do you have baseboard? Radiators? Infloor radiant?

Hi,
I have baseboard heat. I just checked the valve stem on the expansion tank and there were no leaks. Still has 12 lbs. pressure in it from this afternoon. Bucket did have water from the prv AGAIN!! Man I am totally lost!! Tried everything and nothing changed. WHATS NEXT?
Den

ODDSNENDS4U wrote:Hey Coal berner, Why do you use Buckwheat instead of Rice coal?
Den

Cleaner then rice coal little to no fines Price stays the same all year long unlike rice always available ulike rice .

So the PRV leaked, but was the pressure up? If not, change the valve. Servicemen are loathe to test the PRV because many times they don't seal up. Yours has opened many times and it just might not seal anymore.