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Troubleshooting the Digital Round Honeywell T8775A,C Thermostat in a heat/cool setup

I replaced my classic mercury Honeywell round thermostat wire-for-wire after taking a reference photo of the old installed back plate (white wire corresponded to the yellow terminal, blue to the white terminal).  DIP switches are set to off for circulated water.


The solution to this install problem is that the device waits 5 minutes before turning the fan on. It works fine as I installed it. Thanks for your interest.


  • Empire_2
    Empire_2 Member Posts: 2,343
    More info needed

    Please list what kind of equipment you have.  Did you say circ. water?  4 wires 3 circuits...Heat cool and fan, that's it.

    Mike T.
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