System is only 7 years old. It's a dual zone system that is controlled by a Honeywell HZ311 TrueZONE Panel. Thermostats are nest Thermostats that have been in there for 4+ years.

Seems there has been a bit of a ghost in the machine. Some issues in the past but a tech comes out. Resets the system. Tells me to chance the filter. It runs for a bit then will crap out again.

What's happening the last few : Heat randomly stops. But the blower is still circulating air. I go up there to check the system and try and troubleshoot it. I find the F'ing DATS sensor is just sitting on top of the unit. NOT plugged in. Just monitoring the attic temp. I figure that's got to be the issues. I figure a tech was working on it and forgot to put it back in. So I insert the DATS sensor thinking I've got it sorted.

This morning once again. Fan is blowing but no hot hair. When this happens the heat light is flashing red on the controller board. In the manual it seems to point to a DATS sensor error.

Worth it to just maybe replace the DATS sensor? For a $30 fix it might be worth it. What else should I check? Is there a way to check the DATS sensor with a multi-meter?

The HZ311 Controller board was replaced about 2 years ago when it went screwy.

Works fine with A/C?
I would bypass the truezone box and wire one stat direct and see if it is the heater shutting down.

You will have to manually open the dampers of course.

No trouble codes from the heater?

quote:

Originally posted by Mikito:
Works fine with A/C?
I would bypass the truezone box and wire one stat direct and see if it is the heater shutting down.

You will have to manually open the dampers of course.

No trouble codes from the heater?

We had a one or two times during last summer we had to reset it. But not like we are having suddenly this winter. About every 2 days I have to reset it.

How would one read trouble codes from the heater?

Only code I've seen is this one from the manual: Blinking Heat LED (Led me to the DATS possible issue)
https://forwardthinking.honeyw...stall/69_2069efs.pdf

Ok. After reading the troubleshooting link I would try replacing the DATs sensor.

Especially if its replace it or call a service tech as your two options.

Another thing. I just checked and mine is an HZ311 also but I am not using a DATS in my setup. You may be able to just disconnect it and see what happens.

Come to think of it. When I had to shut it down in the summer and reset it. I had to let it sit and thaw. It was froze up. My guess is the DATS sensor never reported the proper temperature. Letting it freeze up. Since some knucklehead just removed it and left it sitting on top of the plenum.

quote:

Originally posted by myrottiety:
System is only 7 years old.

Ok, so you have a 7 year old HVAC system.

Brand?

What is it... ?

Gas fired furnace with A/C
Dual Fuel
Heat Pump
Geothermal
Electric

Model numbers?


***Probably safe to say there's a static pressure bypass damper (since they installed the DATS) and that you have a gas fired furnace (reaching the 160F limit). Tripping the DATS, but also tripping the furnace limit and putting it into lock out mode (which initiates the main blower).

No matter what, you need to measure the plenum temperature while running it for 10-15 mins. Measure the temp during a call for heat on Z1 and Z2. Then measure the plenum temperature for each zone separately.

This message has been edited. Last edited by: Excam_Man,