If you find that your natural gas heater doesn't get your house up to the 70 that you want it to, would putting the thermostat at 75 help? Surely it won't in such a situation.

However, assuming the system can reach the setpoint and cycle off ... raising the setpoint of course will make the indoor temp warmer. Being that the delivery air temp is warmer than the room temp, it *feels* much warmer with the heated airflow happening.

As outdoor temps go lower, temperature differences between rooms can become larger. The home will get draftier too. The increased drafts can be caused a number of ways. The walls, ceilings and, especially, windows are colder so the convection of cool air is stronger. The force-air heating systems are running more and pressure imbalances they often cause can suck in more outside air due to constant running.

This all causes occupants to feel colder even though the old, trusty t-stat says that it is the same,set, temp inside as it is on much warmer days.

If one has a multistage heating system, raising the thermostat will push it into the 2nd stage. Heat pumps will activate auxiliary heat if the thermostat is raised more than 2 degrees from the setpoint.

weedmeister,

This is not the case with everyone's system.

I have my "lockout" temperatures for my auxilliary heat and also my HP set at the same 25 degree temp.

Thus, at no outside temp is aux heat called for due to setback recovery temp differential.