Boiler running(heat) when thermostat set low

[long island]

Hi, I woke up last nite and my house was 85 degrees
but my thermostat is set to 70 , its was calling for heat
when its was not set anywhere around 80..
I have a LUX dig thermostat line voltage

 

[Dave T]

I have never come across this but check your batteries and be sure there is not a program that is set in the stat that automaticaly adjusts the stat up and down that is off kelter, mine has preset day and time and temp features and will adjust according to the stat preset..Check your zone valves some zones have an (open) feature that allows you to flip a switch and use it as an overheat loop in a power out situation, check your stat wires to be sure connections are good..Good luck,Dave

 

[strmh]

Are you certain that the thermostat was calling for heat? I've run into a similar situation where hot water kept flowing through a zone even though the rooms were up to temp.

The problem has been the check valve (just after the zone circulator).......it will, at times, stick open and water will continue to flow when the zone circulator is off.

So far, it's been a simple fix....a few taps on the check valve has solved it every time.

 

[Gene C]

What brand of boiler are you using? If it is a Tarm, did you wire the boiler "overtemp" aquastat to a zone in the house as instructed in the manual to get rid of excess heat if the boiler gets too hot?

If this is the case, turn the temperature control knob on the right side of the front Control panel slightly counter-clockwise to lower the boiler high temp to something below 195 degree F. (89 degree C)

 

[steam man]

Makes me remember the time my dad did a service call for the same reason. Boiler always ran even when the low voltage thermostat was set low. Come to find out, someone drove a nail into a wall and shorted out the thermostat wires.

Mike