Peerless condensate loop not working

TOM DUFAULT

Good Evening,

I have a friend that has an older Peerless boiler and has a hydronic open loop of heat in his finished basement. His problem is that the hydronic open loop is not getting hot. The water is circulating, and we even replaced the circulating pump, and still the feed pipe was luke warm at best. we bled, bled, and bled the water loop some more with no luck. I pulled the check valves apart and found 1 to be bad, left the guts out of both for no question in the check valves interfearing, with same result. I opened both the feed and the return on the back of the boiler, and ran a drain snake into the holes, with no restrictions. Reconnected after snaking with the same result. At this point, I decided to create a small water loop in the back of the boiler between the feed and the return line, the top of the loop was just below the water line, and the pipe got hot, with the larger loop running cold.

The same boiler has a tankless water coil that has been connected to a seperate electric standard 50 gallon hot water tank through a manually controlled by knob mixing valve. I do not think the connection to the water heater is necessary.

Can I use the tankless connection to heat the hydronic loop in the basement, and if not, is changing the return to go through the mud leg another choice to circulate the water in this section to redirect the hot water towards the feed on the mud leg? I spent over 9 hours working this issue yesterday, with very little progress. Any help would be much appreciated.

bob young

loop

pressure test the loop to make sure there is no obstruction.install pump on supply pumping out of boiler.

Al Letellier_9

hydronic loop

Hard to say without seeing, but you said the supply and the return at the back of the boiler??? If both are taken off the back section, you could be short circuiting the flow only thru the back section and using all the boilers output. Also, what is the aquastat set for to keep the boiler hot for that coil. You may have to raise the temp. If all the hydronic piping is below the water line, circulation shouldn't be the problem. If ANY portion of the tubing does go above the water line AT THE LOW WATER CUT-OFF POINT, you need to reinstall the flow checks to trap the water in the hydronic loop.

TOM DUFAULT

There is a loop drain just prior to the return side of the boiler, and if you open it after getting all of the air out it flows great. The pump is on the mud leg at the bottom left rear of the boiler, running perpendicular from the leg. It is when you seal the loop back up where it has issues circulating. The bypass loop that i put between the pressure side of the feed line and the return gets real hot, but the heat loop will not.

TOM DUFAULT

The feed is comming off the mud leg with the pump running perpendicular to the mud leg, and the return is running right in back of the fire box, in the back of the boiler. The check valves are after the pump just prior to going to the ceiling, and just prior to re entering the boiler. The aquqstat was at 180F, and I even cranked it up to 205F, with no change in the water temp going through the loop. You can actually feel the water circulating through the loop, but it does not get hot. If you push the water around somehow in the boiler, you can get a slug of hot water to go through the loop, but then it goes warm to cold, to warm. The loop does go above the low water line, it actually goes to the ceiling, and then down. The return comes back floor level, and steps up 12 inches just going back into the boiler.

bob young

air

Sounds like it is air bound. try filling loop with a hose & locking with checks to prevent vacuum.