Honeywell cm927 Thermostat thinks room temperature is 40 deg

11 Nov 2012
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United Kingdom
The batteries ran low on the Honeywell CM927 Room thermostat I changed the batteries and even though the room is about 18 degrees centigrade the Thermostat thinks the room temperature is 40 degrees centigrade. Does anybody know how to reset this or is it a case of getting a new Thermostat.
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Thanks got a temporary solution until shops open I put the thermostat in the fridge it thinks its 23 degrees c then the heating is working now I have set the temperature calling to 35 degrees c, thus heating on, hot water was all ok as its a combi boiler. Just got to remember to take the thermostat out of fridge tonight :LOL:
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