The furnace won’t heat faster if set higher. Turning the thermostat beyond 72 degrees will not make the furnace work harder or faster than just setting it at 72. This is one common error made by many thermostat tweakers. Your thermostat, although a variable apparatus for adjusting the temperature from warm to cold, only sends a yes or no signal to the furnace.
Once a thermostat detects a temperature that is lower than its setting, it turns the furnace on. The furnace works at only one speed. Cranking the thermostat up to a higher setting will not make the furnace work harder.
Cranking up the thermostat will only cause other problems. Unless you are constantly monitoring the temperature, chances are the furnace will operate too long and get the house too warm. This will make the house seem even colder when you discover the house got up to 75 degrees and you set it back down to 72.
What you can do is monitor the variance in temperature from the coldest the house gets to before the furnace turns on, to the hottest it gets once the furnace turns off.
If you find the variance in temperature to be greater than five-degrees, you can tweak the anticipator on the thermostat. In most cases the anticipator is just under the cover of the thermostat.
The starting setting on an anticipator should be set to the amp reading found on the furnace gas valve. It can be tweaked to compensate for the size of the furnace in relation to the size of the house.
According to Honeywell at Honeywell.com, “The recommended anticipator setting for a forced air furnace is ‘.4’. If the furnace is running too long set the thermostat to the next smallest number. Try a setting for a few hours before making an adjustment. Only move the anticipator one setting at a time.”
If the temperature variance of your house is greater than five-degrees try setting the anticipator one notch lower. As Honeywell recommends let the unit work a few hours and see if the house does not seem more comfortable. The variance should be less and that might be enough to keep the hot and cold flashes from sending your energy bills through the roof.
When in doubt call in your furnace man and let them check the amps on the furnace valve and if need be set the anticipator for you.
Do not short out any of the wires on the furnace control valve or you may need to replace the thermostat.