Thermostat/Furnace ?

[Zoolou]

I have a Lennox G24M Series Furnace....Lately the furnace fires up and then turns off repeatedly and then turns off....I have it set at 22 C . I haven't heard it do this before just wondering if someone might know what it could be.Is it possible that i may have a faulty thermostat??? Just bought a Noma 5+1+1 Programmable Is this safe to use on this furnace...Cause it say on the inside not to use with 12V/24V

[Pete_Coach]

Is this a problem since you installed the thermostat?
If so, you probably wired it wrong.
Yes, some thermostats need to be wired to the house wiring system and will not operate off the 12/24 volt wires from the furnace.
You need a thermostat for your furnace, not all are equal. Some are for electric baseboard and they will not work for you. Be certain you have the right one.

[Zoolou]

Just picked up a Honeywell RTH4300B Stat in exchange for the Noma...Guy at the Home Depot said should be no problem

[loudsubz]

could have been the heating/cooling overshoot was not functioning properly. It basically means that it will heat your house a few degrees over set temp and let it fall back, to eliminate the furnance from turning on, and turning off so fast because the temp hasn't changed much from the set point. Some Tstats you can set the overshoots manually. I like to use 2 degrees minimum overshoot.

[synaptech]

Do a search on the NOMA (here and other sites) to find some of the same experiences with that thermostat.