Heating, Air Conditioning, Fridge, HVAC/Installing line volt thermostat



I have 240w baseboard heaters in my condo. They currently have Honeywelll dial type thermostats and I want to change them to a new Honeywell Digital unit (non-programmable Line Volt PRO 7000).

I have 2 concerns: 1. The existing unit uses 2 black wires. The 2 red wires on the unit just feed back into the back of the thermostat itself (not used). The new unit has 2 red and 2 black wires. I assume I can just wire nut the red wires and use the black only just like the old unit.

2. The new unit use 14 guage wire while the old thermostat had 12 guage wire. The baseboard heaters are hooked up to a double. Pole 20 amp breaker. Does the thinner wire on the thermostat itself make a difference. I didn't think its good to tie 14 guage wire into 12 guage.

Any help or suggestion would be greatly appreciated



Looked briefly at your stat
Voltage Range


Full Load Amps @ 240VAC


Contact Rating Resistive @ 240V (A)


Your new stat is rated for 15 Amps, that is why it has 14 Gauge wire and the Contact points are rated for 15 amps. I would not use it if your heater draws over 15 amps. Your breaker is a 20 and you have 12 gauge wire. If indeed your new stat is rated for your heater ( look at the date plate on the heater to see what's it draw amperage wise at 240 volt.If it's over 15 amps do not use your new stat. I do not understand ,doesn't the new stat have a detailed wiring diagram? I would call Honeywell ( I'm sure there is a number to call with questions ) somewhere on the wiring diagram. If you have a meter , check to see what two wires on the new stat is the switch and opens on temp. increase or closes on temperature decrease.  

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40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

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