Circulator won't turn on for one zone???

Adam E

I've got a 3 zone monoflo system with one Taco 007 that's not behaving..

In the morning when I turn the t-stat up, it takes at least 10-15 minutes for the burner to kick on and the radiators (BaseRay) very slowly heat up. The other two zones seem to be fine.

Now, I'm no expert, but it seems to me that the circulator isn't on and it's heating up from gravity.

Does this sound like a bad Honeywell zone valve (V8043F1036 with terminals)?

Is the pump fired with a contact closure? If so, can I jumper two of the terminals to see if it fires the pump? I take it this would be the end switch terminals?

Also, What's up with the three other wires going to TH, TR, and THTR. I would expect only two to supply the 24v.

I'm prolly way off base here so be kind.

Thanks.

jim lockard

Yea

Adam-- With kindness perhaps it would be best for you to consult a pro. Best Wishes J,Lockard

Weezbo

manually open that zone valve.

if it gets hottern blue blazes then dont put your hand on it again:)

Paul Mitchell_2

That Zone

If thtat zone heats up when the other two are on then it could be the end switch in the valve. If it doesnt matter then it could be the valve itself...but that does not happen often. also make sure there is no air in the radiators or baseboard.

Adam E

Jim, I understand your concerns. I was just hoping that if I could isolate the valve as the problem, I could easily swap it out myself.

Thanks.

Unknown

Is one Taco 007

controlling the 3 zones ? It sounds like the end switch for the problem zone isn't turning the circulator on .

Try turning off the other 2 zones and keep the problem zone up . See if the zone valve opens , and if the circulator turns on .

Adam E

Yea Paul, if another zones calls for heat while that first one is on, then the pump turns on and everything heats up nice.

If it is an end switch, does that mean a whole new valve?

jim lockard

ok

If you wish to try good luck. J.Lockard

Adam E

Ron, yes - one Taco for three zones.

When the other two zones are off, the problem valve opens with no pump action and very slowly heats the radiators.

Thanks.

Paul Mitchell_2

Valve

Depending on the age of the zonevalve you can probably just change the powerhead assembly...without draining any water. I would rcommend you call a pro though.

Joe Mattiello

Pump is not always at fault

If you have 1 007 circulator, 3 zone valves, and only 1 zone is taking approximately 15 minutes to energize the boiler, then the problem clearly is the zonevalve, and not the good old faithful 007 circulating pump. The zonevalve may be stuck in the open position, and allowing flow through, when another zone is calling for heat. Hopefully, you have Taco 570 series zonevalves on your system so you can replace the actuator only, and not have to drain the system, or spend more money then you need too.

Taco, Inc.
Joe Mattiello
Technical Service Technician
joemat@taco-hvac.com
401-942-8000 X 484
www.taco-hvac.com