How do I set the heat at 75 with no fan mode. I don't want the fan to come on once the room reaches 75
Hi, there is no way that this can be done. The fan is controlled by several different parts for the furnace to run properly. If you are saying that the fan continues to run after it reaches its set point, this is normal if it only runs for about a minute and 1/2. This is to cool down the heat exchanger. If it continues to run all the time after reaching its 75 degree set-point, you have a fan relay that is sticking internally, or a high limit switch that has failed and depending on how old the unit is, it may be what is called a combination fan/limit control that has dirty or burned contacts which will keep the fan on. What I am trying to say, is when your unit reaches the temperature you want, the fan should only run a short time as the limit controls are there to shut it down from a setting on the fan control that is preset by the factory. If you can give me more information on your unit such as model, serial, name of unit, and if it is a gas fired central heat and air unit, or heat only, a heat-pump ect. would be of a big help to determine what controls you have on this unit that is keeping the fan on. Leave this info in the comment thread for my user name, and I will get back to you.
A/C, Heating, & Commercial Refrigeration Contractor