View Full Version : hot zones not calling for heat

04-04-2009, 05:13 PM
I have 5 zones in my house and now that it is spring none of them are calling for heat except for my hot water superstore. Unfortunately the hot water is passing into the other zones. I did have to replace my taco relay last year due to a lighting strike. Any help?

04-04-2009, 05:41 PM
How are your zones separated. Valves, pumps, ??? If valves are they stuck open? If pumps are they running same as main or HW pump?

04-05-2009, 04:58 AM
I have circulators. Keep in mind that all of the zones are getting hot. The circulators are not running when this happens. I tested circulators. No power from relay when this is happening. I labeled every wire when I replaced the board after the lightning strike so I'm almost positive that its not a wiring issue, however I'm not ruling that out. What about flow valves. The hot water is passing through the circulators when they are not on. Kind of like siphoning I guess. My house is 4 years old.
Thanks for the help.

04-05-2009, 05:39 AM
When you turn a thermostat up does a circulator run?

If no than you either have a thermostat problem (not likely) or the zone relay is bad (likely)

If the zone gets hot and the thermostat is not calling and the relay is not energized than your check valve is open (very likely)

If your check valve appears to be closed but water is still getting by then the valve is stuck (bap it smartly with a hammer)

I suspect however that you need to replace the zone controller as the lightning strike probably fried the priority circuit so that only the water heater will run.

04-05-2009, 06:23 AM
Im not sure if i do or do not have a check valve? I have a 1 1/2" pipe coming out of the top of my boiler passed the low water cutoff through the airtrol and into the manifold dividing the circulators.
The circulators work for each individual zone when the thermostats activate them. So thats not a problem.
The relay board is brand new. I just put it in 3 months ago.
Should "check valves" be on each individual zone?

04-05-2009, 11:26 AM
Yep, Taco 219 or it's equivalent. Heat rises and so does hot water. With no check valves, any time any zone runs, they all get hot.

04-05-2009, 04:06 PM
Thats great thanks for the info. Where should i locate the check valve(s)?
Before or after the circulators? Im not sure why my plumber at the time did not do this. Could there be a rreason?

04-05-2009, 06:53 PM
After the circulators.

04-06-2009, 01:47 PM
Confused again. If the check valves are placed after the circulators what stops the hot water from passing through them? Does the pressure from the circulators allow flow through the check valve, but stops water from passing into the zone when it is not being actuated?