Replace T451a 24v thermostat with programmable

Old 01-03-20, 12:20 PM
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Replace T451a 24v thermostat with programmable

I have 2 Honeywell T451a thermostats connected to a two wire 24v system. One for each of two zones. A black wire and a white wire. I checked with a multimeter and it is around 27 to 28 volts. It is an oil burner - hot water system with baseboard radiators. I would like to replace with programmable thermostats. Any ideas on what would work?
Old 01-03-20, 06:07 PM
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Just about any thermostat that runs on batteries will work.

A Honeywell TH6110D1005 runs about $48 and will work.

A Honeywell touch screen TH8110R1008 runs about $133 and will support your equipment.

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