1 radiant loop not heating

haventseenenough

Gotta heating system in a relatively new home. WM gv6,5 zones Honeywell zone valves not full port. Primary secondary pumping SS 80 tank (no problems there) no injection control, mixing valve is used. The house is not piped well. Supply and return piping goes every which way. The farthest loop, that does not heat well has 3/4" s@r into 1/2" wirsbo no purge manifolds for each zone all done in mech closet. Replaced mixing valve and went from a taco 007 to a 008 in hopes of increasing flow. no ifc in any  pump. Power purge system no air, seemingly good flo. No check valves on primary, domestic, or secondary loops.Any thoughts Thanks.

Alan (California Radiant) Forbes

Can you

turn on only that zone and close down all the loops except the one that's not heating?  If so, do you get flow and heating in that loop?

haventseenenough

1 radiant loop not heating

Alan, Shut down the other 4 zones, disconnected dhw aquastat some movement but no real heat. Waited an hour no results. S@R run in the ground for a bit and insulated. still scratching my head. This has been a problem for 4 years. The laundry list of work done is long and varied.

Mark Eatherton

Bubbles...

Sounds like it is air bound to me. If not, you'd be getting SOME circulation...



No way to easily purge it out?



ME

icesailor

Loop not heating:

The other thing if it has always been a problem from the beginning is that something is stuck in the tube or there is a kink under the floor. It may not be easy but I personally would figure out a way to get my air compressor on that loop an blow it back. Blow all the water out of it and see what kind of a blast of air you get back. You may have a way to close off the other loops and purge with air, that loop. If the water comes back slowly, there is something wrong in the loop.

I have a very old copper radiant plastered ceiling job that I split the second floor zone into two so I could get two thermostats. In the master bedroom, there is a circuit like this. The heat in this room has never worked properly. I know that there is a problem in this loop but I don't dare try to fix it.

I found this problem with a infra-red heat thermometer gun. Perhaps, if the loops are close to the floor, you could shoot the floor and find the loops. Then, look for the one that isn't working. You may find where the problem is. 

haventseenenough

1 radiant loop not heating

I've purged this system till I get no bubbles. It still does not heat well. I can isolate that one loop, but would feel a lot better if I could see the supply and return manifolds. not in crawler or behind any visible access panels. Thank heavens for understanding customers, they can help make a troubling job easy.  Thanks

icesailor

1 radiant loop:

If you can't see the manifolds, or get to them, how do you know that you purged the one not working? If the manifolds are under or in the crawl, you should call the idiot who did the install to come out and help you purge it as punishment for doing something as stupid as that. If it has never worked, maybe that's why it doesn't work. It's never been purged.

haventseenenough

1 radiant loop not heating

The job was done by a fly by niter can't find him don't want to. Broke out the multi meter toned out the wires to the corresponding tstat,zone valve. Its the only zone not working well. Most likely as you had said debris in the tubing. The copper s&r  go thru the poured finished floor and up thru the dirt in the crawler. A home run from the mech closet to the zone I'm guessing. Thanks

icesailor

Loop not heating:

I may not be telling you anything but, if you can get into the return piping of the loop, take an air compressor and blow it backwards. If it is possible, you might blow out the obstruction.

I recently was called to a high end house that had just had an addition. The contractor moved the cellar wall out and there was a 1' space outside the wall for the submersible well casing. The roof had an overhang, covering a deck. Under the deck was the well casing. accessed by a hatch. The outside grade was brought up to the bottom of the deck so there was just one step to grade. The grade under the deck was left alone and there was 2' from the grade to the bottom of the deck joists. Water running off the roof ended up going under the deck. Flooding the under deck. A week of rain really flooded it. Muddy water went over the well cap. The water drained into the screen that lets air into the casing. The screen filtered the water only allowing very fine sand into the well. The pump pushed the sand all through out the potable water system. I was told that I was the third person called. I blew it all out with compressed air. Even the toilets wouldn't fill. The owner had bought all the high end fixtures off the Internet. No support or availability of parts.

My portable hot dog tank air compressor is my most important tool in my truck.

haventseenenough

1 radiant loop not heating

Advice well taken. Probably a spring time job. No real pressure from the homeowner. This has been going on for quite some time. Thanks

Mark Eatherton

Find the manifolds with Infrared camera...

It's like having XRAY vision. You can see the tubes right through the wall with just a LITTLE heat and flow in the tube.



Had a home a while back where ALL of the manifolds were buried in the wall. I was able to identify each and every one of them for the owner. He said he'd dig them out at a later date.



Cameras (FLIR) are as low as $2k these days, and you can rent them before you buy them if you want.





ME