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Mystic Jay
No water pressure in boiler

Evening everyone,

I was hearing the sound of water running in my baseboard heating everytime it kicked on, so I went down and checked the furnace to find no pressure on the gauge that says water psi? I tried to manually fill it with auto fill? regulator but I cant hear any water running through it. The system goes from the well to the backflow preventer to the auto fill(I think thats what its called). Do these things fail? or could it be something else. I think the backflow preventer works because I have hot water at the tap.

Any ideas would be so helpful!

johnjh2o
Re: No water pressure in boiler

The auto feed needs to be repaired or replaced. Most times replacement is required.

John

Mystic Jay
Re: No water pressure in boiler

Thanks John,

Is that something I can do myself or do you think I shouldnt go near it. The way its set up seems pretty simple to replace, just threaded black pipe.

Thanks again.

johnjh2o
Re: No water pressure in boiler

It's not that difficult to do. You may have to change some piping as chances of getting a exact replace may take some looking.

John

Dobbs
Re: No water pressure in boiler

Mystic,

There's almost always a simple manual water shutoff valve that's located before all the other valves you mentioned; its purpose is to isolate the well water, which is at approx 30-40 psi from the boiler water, which is at approx 12 psi----make sure this manual valve (if it exists) is open.

If THAT valve is not the problem, it's usually that the internal screen at the bottom of the preessure reducing valve is clogged with minerals (especially seeing that you have well water).

Before replacing the PRV, turn off the water line coming in from the well water & unscrew the bottom of the PRV and clean out the accumulated crud from the screen & replace the screen & screw-in cover.

The purpose of the backflow preventer valve is to prevent undrinkable boiler water from getting into your fresh water supply in the event of well pump failure & loss of the usual 30-40 psi present there; it has nothing to do with your hot tap water supply.

Another possibility is that you have a leak somewhere in the system---look for water at the base of the boiler, as well as any baseboard fittings (bleed valves) or hairline cracks anywhere in the system.

You should not run the boiler if there is a zero boiler water reading; you could overheat & crack the heat exchanger sections.

Mystic Jay
Re: No water pressure in boiler

Thanks everyone for your help,

I took it out this morning and totally disassambled the fill valve. It was full of crud so the actual valve had no pressure going to it. I even lapped it in so it seats nice and tight. The system is holding pressure now so I dont think there are any leaks.

Thanks again.

johnjh2o
Re: No water pressure in boiler

Good job, but I would keep an eye on it. Check to be sure the pressure doesn't exceed 12-15 PSI.

John

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