Racking my brain

Anthony_10

This has been racking my brain for months. My heater does not hold its pressure. It is your basic hot water radiator home heating system. I was told on this site that the compression tank has nothing to do with pressure. But when I fill my system to about 15 psi then open up the expansion tank valve, my pressure drops to zero. I know my valve to the exp. tank needs to be open, because when you heat water, you make more water and where does this water go? Right, the exp. tank. Plumbers have told me to add an automatic fill valve to the system, but isn't that an easy way out of fixing the pressure problem? I also have tried draining my exp. tank ( someone said that it could "water logged" ). This seems to help for about 3-5 days, but eventually the pressure drops. I think that I don't need a plumber, but I need a heating troubleshooter to come and see if everything is how it should be in my system. I was also told that I may have a leak INSIDE my boiler, where it evaporates and escapes through the flue. Is there anyone who knows any heating troubleshooters in the Deleware County PA area that may be able to solve this problem before NEXT winter. I've been playing with this system throughout this winter. My downstairs rads get hot and my 2 bedrooms upstairs get hot. The 3rd bedrom has the problem when the pressure is at 0 because the water, I believe, can't get there by the circulating pump ( which I have changed also ). Can anyone help me out here??? I'm at my witts end. Thanks for listening.

Mike T., Swampeast MO

Will try, but need some info:

Is it an old plain tank or a newer tank with a bladder and air connection (like on a tire)?

A problem with either generally leads to increased pressure--that's why people are suggesting a leak--even one "hidden" in the boiler.

Anthony_10

It is an old style exp. tank that sits above the heater in the ceiling.

Mike T., Swampeast MO

In operation and at system pressure (typically 12#) it should be about half full of water. Does it empty when you loose pressure? (You can usually lift one end slightly and get a very rough idea of how much water is inside.)

Have you completely bled the air from all of the radiators? Standing iron rads don't trap bubbles so if you get nothing but water, they're OK. BUT, big old systems can take quite a while (like weeks) for air to stop collecting in the tops of the rads.

Any old capped off branch lines? If so, they'll trap air and it can take a VERY long time to eventually migrate to the radiators.

The problem with plain old tanks is that water can circulate slightly via gravity into and out of the tank--the pump CAN'T do this, but gravity can. The air dissolved in the water that circulates out of the tank drops out of solution and winds up in the radiators and the pressure will drop when you bleed the air. Then you add more water to bring the pressure back up and the cycle continues until the tank is gets so full of water that there is no longer an air "cushion" and the system pressure starts to climb as it heats. Continue the process long enough and the pressure relief valve finally opens.

Get (or have installed) a Bell & Gossett Air-Trol fitting on the tank. It prevents the gravity circulation that causes the problem. Follow the fill instructions that come with the fitting carefully, but if this is an old gravity system you can forget about the step that says to disable the circulator and heat the boiler to 220°. (The heat aids in the initial air removal, but the systems contain so much water that just heating the water in the boiler itself won't do much good.) Good to rig the circulator for continuous operation and leave it running a few days with the boiler off. Then vent the rads. Then re-wire the circulator and use the boiler for a couple weeks and vent again.

If the system continues to loose significant pressure after all of this, you can fairly safely assume that there is a leak.

Weezbo

someone will help you Anthony.

try find a pro here or and if that doesnt get it try the radiant heating panel associations find a pro... i am inclined to believe there is indeed a leak in your system ,and that the boiler is heating the water enough to give you heat.of sorts.fixing it on your own is simply a stress and strain on you, as there isnt anything clear cut that you can identify as the source.and without a picture of the boiler room or a means to communicate exactly what to look for step by step it is just adding to your general frustration..........Someone will help. my attempts have been thwarted because you think for some reason the way i say things is designed to urinate you off.it isnt.i really understand how much fricking hassel it is for someone who is only seeing the trunk of the elephant to describe what the "Thing" is doing and all the running around after it to keep up with whats going on. i will say it again,turn off the boiler ,wait till the temp goes down to 100F (about an hour)purge every line,isolate the individual zones,open them one at a time,run the zone for a half an hour ,close it,open another,make sure the pressure hasnt changed in the boiler each time you do that,open the last one run it for a half an hour or hour,see if it is the culprit...if there is no reduction of pressure on a line then it is likely it was simply air locked, if none of the zones cause a reduction in pressure (always at the same temperature reading) in an hour and a half,then the next places to look are the boiler and associated piping,turn off all the zones and run the temp up no visible leaks?,then shut the power off open the boiler door or if it doesnt have a door remove the burner look inside the fire box or chamber (if it is oil)if it is atmospheric gas then youll need a flash light to look at he lower area of the boiler above the burner, if it is a gas Gun burner take it out just like a oil burner, what you are then looking to find is a sign of white or red or actual water itself leaking ....this then is an indication where its comming from. unless certain things are noted as they are discovered theres no way anyone can divine the answer.if there are no signes of water or condensating steam or long term leakage thru the gaskets or sections on that side of the equasion then the other side needs to be tested and visualy inspected quite often i will also pull the "skins" off the boiler at that time to make certain i havent missed the obvious before embarking on dragging out more tools and instruments ,for this reason i only told you the easiest things to look into on your first post.and at the same time i said what i did because thats how i say what i say and thats exactly what i mean...not something else. the reasoning behind it is that it at least etches into ones mind the importance of doing things safely and that there are consequences to our actions.kow tow to God .i intend to put off meeting him as long as natural selection doesnt take me out.i also dont send people out on fools missions, if some one is going to be the lead on that it wont be someone who i am advising or who trusts my word.it will be me, as i am better able to contend with and read the variables immmediately.thats why i suggested getting someone who knows what they are looking at ..it would save you considerable amount of time and vexation.

Richard_4

Install the auto fill and a back flo preventer which is installed before the fill valve. Fill the boiler and expansion tank at same time then purge radiators. After a day or two feel the auto fill, if the fill pipe is cold or you can hear water running through it, your leaking water someplace. are there any underground pipes or hidden pipes in your system?

JimGPE_3

Anyone else

think this sounds like a leaking expansion tank? Perhaps a plugged fitting that is leaking the air out of the tank?

Al Gregory

No PRV and probably no LWC. Time to come to the 21st century and get a Pressure Reducing Valve with a backflow preventer. A nice Extrol tank would be nice too.