Boiler psi zero

lisap

Should my pressure gauge ever be at zero.it seems to be running ok and heating ok but shows zero psi .  Yesterday it fluctuated from 8 - 15 psi  but now zero.  If I  add water it lasts for a couple days and now reading zero again. It is a brand new boiler and they came out once already and added water. But still a problem. Any ideas

GGross

I suspect you have a leak somewhere. When filled the system should not lose any pressure from its cold fill, you may see the pressure rise somewhat during a heating cycle, you may drop pressure somewhat as the system purges out air (though the installer should do this before finishing) If you are at 0 PSI and fill up to 12-15 and then it goes back to zero, I would highly suspect a leak somewhere.

MaxMercy

lisap said:

Should my pressure gauge ever be at zero.it seems to be running ok and heating ok but shows zero psi .  Yesterday it fluctuated from 8 - 15 psi  but now zero.  If I  add water it lasts for a couple days and now reading zero again. It is a brand new boiler and they came out once already and added water. But still a problem. Any ideas

What controller is it using? I'd be worried about a low water condition but most controllers have a low water cutoff.

hot_rod

How long has it been running? It could take days, or longer to purge small air bubbles. Water needs to be added as air comes out,
the type and location of the air purger has  a lot to do with how long it may take 

lisap

They came out over a week ago and added the water. Held for a couple days . I have added water a few times. Other than zero pressure. It is heating nicely. No error codes.  Is it normal for me to add water this often and if so how long should I give it until I have them out to diagnose again. I really hope it isn't a leak. That sounds like a nightmare 

psb75

The further question to ask is: why isn't the auto-filler not getting it back up to pressure? Assuming you have one. I would tend to trust and I'd pay attention to the new pressure gauge. That scenario can go on for quite a long time...and still be a leak. Worth investigating. You could put another pressure gauge on the boiler drain for further verification. Often the boiler itself has its own temp/press gauge. More data = more better.

GGross

do you have some pictures of the boiler and associated piping? In general no it is not normal to need to add water to a closed loop hydronic system.

EBEBRATT-Ed

You could have a defective gauge or a defective expansion tank.

Alan (California Radiant) Forbes

Fill valves often get stuck and stop keeping the system filled. The good part is that it lets you know there's a leak or some other problem.

If the pressure has been zero for awhile, it could have sucked in some air, so keep filling it and let the systems rid itself of the air. If it continues more than a week, there's a leak somewhere.