Page 1 of 1

Dual Fuel Trane xl400

Posted: Tue Jan 07, 2014 9:25 am
by calicojake
This morning I tapped the function key on my thermostat to read the outside temp. and it displayed the - ' - -' instead of the outside temp. and it also - 'service' & 'outdoor'....Also, the gas furnace did not come on but the heat pump did come on 'Stage 1' ...which is heat pump only and not the gas furnace. The temp. outside was 9 degrees so the gas furnace should have been on and not the heat pump. What do you think the problem is? Should I switch over to Em. heat mode to operate the gas furnace or keep it on Stage 1 which is the outside heat pump which is not keeping the inside temp. up to 70 deg.

Regards,
jake

- Dual Fuel Trane xl400

Posted: Tue Jan 07, 2014 2:11 pm
by Freon
Definitely use the emergency heating (gas furnace). The heat pump below about 30 degrees is useless.

I am not sure why you're getting the display on your thermostat. Check the installation instructions. Check if there's a "Service interval" reminder setting in the thermostat that you can skip for now. But do get the gas furnace going.

- Dual Fuel Trane xl400

Posted: Sun Jan 12, 2014 12:48 pm
by calicojake
I called my heating & Air guy this morning and he told me it sounded like a frozen outside temp. control....the one that controls the gas furnace coming on below 35 deg. and the heat pump coming on at 45 deg. to support the dual fuel capabilities. After the outside weather temperatures got above freezing, everything went back to normal as far as gas/heat pump operation along with an outside 'temp' reading on my inside trane thermostat. So.....I guess living in S.C., the trane system was not used to such low, low outside temperatures that we experienced last week. It broke a record down here at 5 deg.....burrrrr.......

Regards,
jake

- Dual Fuel Trane xl400

Posted: Sun Jan 12, 2014 1:08 pm
by Freon
Trane makes fine equipment. And a "frozen outdoor heating control" needs further definition.

You have a temperature sensor outside and that tells the system when to stop the condenser and use the indoor furnace. That outdoor sensor can be wired through the thermostat or is set at the control board in the condenser. I would try and find out exactly how your temperature sensors are set for operation.

It may also be possible the defrost cycle for the condenser was not run long enough to stop the condenser from turning into a block of ice. With very low outdoor temps, this can happen too. Fortunately such cold is the exception and you can pull the disconnect on the condenser and run only the furnace if necessary.

- Dual Fuel Trane xl400

Posted: Thu Jan 23, 2014 10:58 am
by calicojake
If I change the 'mode' on my inside Trane thermostat from "AUTO" to "EMHEAT" allow me to use the gas furnace only?

- Dual Fuel Trane xl400

Posted: Thu Jan 23, 2014 1:40 pm
by Freon
Yes it should, depending on how you have your system setup in the thermostat installation program.