How to lower my boiler pressure a little

rickhow

Recently had a company fix a leak on my boiler (heating). One of the shutoffs was dripping. I'm not a guy who can successfully solder . My boiler always had pressure during heating season of no higher thant about 17 or 18 when hot, worked fine. After fix he purged a couple of 5 gallons pails of water out and refilled, but he adjusted pressure and it now sits at 20 all the time. (Cold here, heating a lot). What the best way to drop this down 2 or 3 points. Let it cool, drain out a bit of water until desired pressure, then stop drain? It will refill to proper level with pressure reducing valve?? Or do I have to refill it by opening the reducing valve until desired pressure??

Jamie Hall

Just close the automatic feed (there should be a shutoff on it), open a drain a bit and watch the pressure gauge until it gets to where you think it should be. Then close the drain and reopen the automatic feed. If the adjustment on the automatic feed is correct, it should perhaps rise a bit, but stabilize.

Note: if the gauge doesn't respond in the first step, there's something amiss with the gauge -- which wouldn't be a bit odd. You will need a better gauge tapped in somewhere.

HomerJSmith

It depends on what is regulating the sys pressure. Jamie Hall is correct if you have an independent feed valve. However, if the pressure is regulated by the expansion tank, such as a Filtrol 110, then the sys pressure is regulated by the air charge on the expansion tank.

It may be that the sys was over charged when the tech filled the sys, in which case, I would just open a hose bibb valve on the boiler or piping and drop the water pressure to 15 psi on the boiler gauge. If the pressure goes back up then adjust the independent feed valve (cold water pressure regulation valve) or the pressure on the Filtrol Xtank.

Be aware that the pressure can increase up to 3 psi when a cold boiler heat up the water in it.

rickhow

Thanks guys. I give it a go tomorrow.