Check out some similar questions!

twobks · Dec 21, 2008, 07:46 AM

I have a forced hot water heating system in my home. The furnace is fueled by oil and also serves as my hot water heating system. The furnace is a Beckett EM-125 and it's about 8 years old. It recently started dripping water. There is an open copper tube in the back of the furnace that is dripping cold water. What is the likely cause and how can I fix it.

KC13 · Dec 21, 2008, 08:15 AM

Sounds like the relief valve is either activating or leaking. If the system has a conventional expansion tank it may be flooded.

hvac1000 · Dec 21, 2008, 10:10 AM

If the system has a smaller bladder type expansion tank with a air valve the bladder migh be defective.

twobks · Dec 21, 2008, 04:57 PM

Originally Posted by KC13

Sounds like the relief valve is either activating or leaking. If the system has a conventional expansion tank it may be flooded.

Thanks for the quick response. If the expansion tank is flooded, is it simply a matter a draining the expansion tank? There's a blue knob on the bottom of the tank. Is this a drain plug? Do I need to shut the furnace down before attempting to drain?

hvac1000 · Dec 21, 2008, 05:01 PM

First you have to isloate the expansion tank. Then drain then open up the isloation valve. This is for a normal expansion tank install. Post some pics of the valving so we can see which valves are which.

twobks · Dec 21, 2008, 05:14 PM

Do these help? I just checked on the leak again and now there was hot water running out. More than just a dripping.

hvac1000 · Dec 21, 2008, 05:22 PM

The Extrol tank in the picture is a bladder tank. If the bladder in the tank has sprung a internal leak that will cause the safety valve to leak due to pressure. So It is eighter the safety valve in last picture or the tank in the first picture.

Looking at the gauge in the middle picture your system seems to be over pressured. Take a close up of the gauge and post so I can see it better.

hvac1000 · Dec 21, 2008, 05:28 PM

Just saw another item that could be causing the proiblem. You use the boiler to heat up domestic water for showeres and stuff like that. In the middle picture there is a valve on the water line that oes to a black plate on the boiler right in the front. Turn that valve off for testing purposes. There is a coil inside the boiler that heats the water up for showers that is separate from the boiler heating water. If this coil springs a leak it will cause the boiler safert to leak since the pressures of the two systems are different with the water pressure for the shower water section being higher than the boiler water for heating. This pressure difference will allow the higher pressure from the hot water for showers to enter the boiler and cause the safety pop off valve to leak.

twobks · Dec 21, 2008, 05:48 PM

In the original picture it looks like it was at about 40psi. It had shut down and the psi dropped down to 5. So I turned up the thermostat but the pressure only increased to 15 psi.

twobks · Dec 21, 2008, 05:57 PM

The valve to the right by the American flag doesn't budge. Should I close the one above it?

hvac1000 · Dec 21, 2008, 06:52 PM

From what you just told me when you shut it down and the pressure went down from 40 to 5 then I would be looking at that EXTROL tank.

Usually those tanks are set from the factory at 12 pounds. When you remove the cap at the bottom of the tank there is a tire type inflation valve just push it in for a instant and see if any water comes out or air.

twobks · Dec 21, 2008, 06:56 PM

A drop of water came out. Otherwise just air.

hvac1000 · Dec 21, 2008, 06:59 PM

OK a drop of water is not much. If you have a air pump let all the pressure out the recharge to 12 PSI for the standard system setting. Before you do that see how much pressure is in the tank now before you repressure it. How tall is your home? One story or two?

twobks · Dec 21, 2008, 07:01 PM

And I didn't actually shut it down. When I said it wasn't running I just meant it was idle at the time. I estimated that it had been at 40 psi when the original picture was taken, based on the photot. But I haven't seen it get that high since.

hvac1000 · Dec 21, 2008, 07:02 PM

40 is way to high and will cause the valve to pop off/drip

twobks · Dec 21, 2008, 07:10 PM

Is the meter on the front telling me the pressure of the tank? It's at 8-9 psi now while idle. The only pump I have is a manual bicycle pump. Is that sufficient to repressure it back to 12 psi after I let the air out?

hvac1000 · Dec 21, 2008, 07:26 PM

A bicycle pump should work but you need a tire gauge also. NO the gauge out front is water pressure in the boiler .

Take all the pressure off the boiler. Pump tank to 12 psi. Refill boiler. HOW HIGH IS TH HOME? One story or two. I asked this before.

twobks · Dec 21, 2008, 07:35 PM

It's a two story home with a full basement as well.

hvac1000 · Dec 21, 2008, 07:39 PM

OK increase tank pressure to 16 PSI. Then fill and fire it up. You know this could all be caused by a weak pop off valve but I am sure that has been mentioned before.

But the boiler is never supposed to run at ove 25 PSI when hot. I am sure the pump is also running when the boiler is operating?

twobks · Dec 21, 2008, 07:59 PM

Yes the pump is running.

My tire pressure gauge starts at 5 psi, and the expansion tank doesn't even register. I'll try pumping up to 16 psi. Am I supposed to shut the furnace down before doing this?

How do I take all the pressure off the boiler then refill?