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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I have a Trol-a-Temp controller that operates a 2 zone HVAC

Customer Question

I have a Trol-a-Temp controller that operates a 2 zone HVAC system. The system uses Power Open / Power Close dampers. The Nest Thermostat is not compatible with the Trol-A-Temp. I looked at replacing the Trol-A-Temp with a Honeywell HZ311 but that unit does not appear to be compatible with Power Open / Power Close dampers. Is there another 2-Zone controller that will work with Power Open / Power Close dampers and be compatible with Nest?
Submitted: 2 years ago.
Category: HVAC
Expert:  gotoman for ac replied 2 years ago.
Russ here. Welcome. I am here to help. Please do not rate until you are satisfied with answer. Always available for follow up questions. One moment. The 311 is compatable with your system if it not a heat pump. Straight cool,furnace only. If you need heat pump control go to HZ322 Honeywell and that will be compatible with heat pump. The 311 has M1,M4,M6 contacts to operate power open power close. Russ
Expert:  gotoman for ac replied 2 years ago.
Anymore questions I ma here. Russ
Customer: replied 2 years ago.
Sorry about the delay in responding. Work has been busy this week.I appreciate the response. It looks like it will work. I pulled the manual on the HZ311 and see the list of dampers it can control including power open / power closed. The current damper actuator is a Trol-A-Temp 93-057H-001-00 which appears to have be the same as the Honeywell MSTN. Just to confirm, that the connections from the MSTN to the HZ311 are straight forward - M1 to 1, M4 to 4 and M6 to 6.

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