A small home water heater (for heating) in a two story home what is the normal psi that it should have. I have a closed system running at about 15 psi and the pumps make noise. If I jack the psi up to 30 the noise goes away. What is the cause of this? I am thinking 15 psi is normal. I am thinking maybe the pump is going bad????
Your boiler and water heater pop off at 20 pounds at the pressure relief valves. (Which they both should have) Usually noise is air. Bleed your system to make sure there is no air causing the noise.
15 to 20 lbs. i would say is normal,during real cold weather the system will run alot more and the pressure will rise a little.
I just installed an exterior boiler for my house. Currently it runs (constant circulation pump) 15-18 lbs/sq. in. PSI @ 120-130 F. Mine has an air scoop which auto bleeds air from the line @ the CAT (captive air tank). You should double check the rating of the pressure/temp. safety relief valves, and verify the PSI/temp. are the correct rating for your system. I believe mine are 30/180, but if you have 2 on the system, they must match. Check operation by lifting the lever and bleed any air. Water should just be allowed to escape a bit, then seal when released. I have a dual circulating pump system: 110 Vac for normal conditions (with backup 110Vac motor pump combo): 12Vdc backup for emergency power failures. If you live in cold climes, don't take chances: keep an extra motor/pump at the ready, for fast swap out. Pump bearings are one component that can fail: sounds vary from squealing to grinding. Cavitation sounds are different; more like sloshing water. If bleeding all your lines does not cure the noise, you might want to replace the pump, done when you are ready for it, rather than wait for catastrophic failure a 'do it now or else' situation.
