Boiler issue

[Vista92]

I have a boiler that was installed back in november and since then it keeps losing water pressure and theres no signs of a water leak on visible pipes or pipes in ceiling. I have to add water every 3 days or so or it goes to zero and all the air should have been out in the span of 4 months especially since I bled it after install. What could be wrong?

 

[Geofd]

if its a hot water boiler is the automatic feed also new ?????

 

[Vista92]

I didnt put in auto feed becuase I heard if they failed they could flood the basement. The boiler is a used boiler from 2000 that wasnt used much and the expansion tank and air valve for the tank is new

 

[Diehard]

I didnt put in auto feed becuase I heard if they failed they could flood the basement. The boiler is a used boiler from 2000 that wasnt used much and the expansion tank and air valve for the tank is new

Did you check the air pressure in the expansion tank without any water pressure on it?
You can have a PRV on the system but keep water shut off most of the time. That's what I do.
The next time it goes to zero pressure, check your air pressure in the exp tank.

(Never heard of a failed PRV causing a flooded basement. I don't doubt it may have happened. Typically when they fail, they fail to hold the preset pressure, which I suppose could blow the relief valve.)

 

[Vista92]

I heard if the auto fill fails it could continue to add water and the pressure relief valve would let the water go becuase the pressure. So if the expansion tank is over or under pressure, it could cause me to lose water pressure alot?

 

[frodo]

are you bleeding the air off when you fill it with water at a high point on your base board heaters or the infloor loops?

you should have an air separator and auto fill valve
with gages to see the pressure

 

[Diehard]

Yup...relief valve set at 30 PSI.

By the way, did you install an air separator(called an air scope) and an automatic air vent valve?

Air pressure in exp tank should be set to whatever pressure you have your water pressure set to. Typically around 12 psi cold. But like I said, there can't be any water pressure on it while filling air to 12 PSI. At 12 psi of air, the water side must be no more than zero psi. Either by disconnecting tank or by releasing a bit of water from the system. Whatever it takes.

 

[TomFOhio]

Do you have any underground piping going to a radiator??

 

[Diehard]

I have a boiler that was installed back in november and since then it keeps losing water pressure and theres no signs of a water leak on visible pipes or pipes in ceiling. I have to add water every 3 days or so or it goes to zero and all the air should have been out in the span of 4 months especially since I bled it after install. What could be wrong?

Thinking about this some more. Assuming you have the appropriate amount of air trapped in your expansion tank, to go down to zero PSI, I believe, means your having to add the equivalent amount of water as half of the capacity of your expansion tank every few days or so?? That's a lot of water.

 

[voletl]

Had a customer one time the boiler had no water in it couple of vacations couldn't figure out what was going on it turns out that the boiler was running over the limit and causing the water to steam out the the pressure release the water feed with stuck shut it would not automatically refill the boiler making it the mysterious empty boiler

 

[fixitron]

Assuming that the pressure gage or tridicator is accurate and you fill the system to 12-15 psi when cold, I would expect that if there was so much air in the system that you had to refill every day, then you would not be circulating any water. It also appears that you have had heat. Therefore, I don't believe that the cause is lots of air in the system. The water has to be going somewhere. There may be a leak somewhere that you are not seeing. The expansion tank is either not pressurized properly on the air side, or it is undersized, which would periodically lift the relief valve. I am thinking it is a leak.