Want to use my Honeywell T87 on new Argo control

Old 11-24-14, 11:44 AM
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Want to use my Honeywell T87 on new Argo control

Looking for a little help on using my old T87 mercury thermostat on a new controller. The T 87 won't function properly because most of the new controllers will not provide enough current for the heat anticipator to work.

Should I try to use a Honeywell RA89A which provides a .4A coil/relay for the anticipator. The load side of the relay will then trip the TT on the new controller.

Just like the way the old thermostat works.

Thanks Matt OLDT87
Old 11-24-14, 05:44 PM
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I would replace the thermostat with a digital model that can run on batteries like the Honeywell TH5110D.

Is your old stat a T87 round or a T87 rectangular stat?
Do you have an amp meter to measure the current between T and T when jumpered?


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