Heat

[Atthelake]

I have a 2014 Kropf Park Model- I am trying to understand why when I try to use the furnace I get some cold air? When I go to the thermostat and turn it to HEAT and leave the fan on AUTO the furnace ignites and I feel some heat from the vents. When I switch the fan to ON it blows cold air. Can anyone help me with this?
Dealer is saying heat only works on AUTO? but really doesn’t push the heat out of the floor vents…?
Thank you!!

 

[Mark_K5LXP]

So does the furnace fire when room temp is below thermostat set temp? I can see that the fan would stay on when the thermostat is ON but would expect that a call for heat would also fire the burner. My S&B furnace operates this way. Sometimes I'll turn the fan ON to equalize the temperature in the house when DW is cooking full bore in the kitchen. Looking at the installation/technical data for the furnace unit should describe the modes and what thermostat connections are needed for it to operate.

Mark B.
Albuquerque, NM

 

[Domo]

If the heater has been off - it's exchange chamber is filled with cooled air. So, if you turn on the fan (not to auto) the fan will push that cold air into the room - and will continue to do so until you turn it off. The moving air on your skin will also evaporate any moisture, making you feel cold.

The AUTO position of the fan switch means the fan will ONLY come on when the heater is heating (as set by the temperature control). When the heater does kick on you will get some cold draft as the fan starts and pushes out the un-warmed air, however as soon as the heater ignites it will turn to warm very quickly.

This is pretty much the same as many HVAC systems in a sticks and bricks home.

Don't listen to your salesman.

 

[Gary RV_Wizard]

I'll concur with Domo's explanation. FAN ON means exactly that - the fan runs whether the furnace is hot or cold, so you are going to get cool air part of the time.

In general, the furnace burner should still heat (or not) in response to the thermostat set temperature, regardless of the Fan mode. However, for safety reasons a forced air furnace won't heat unless the fan is running to circulate the heated air, so it's possible your thermostat doesn't send the "Heat Needed" signal when the fan is in a manual control mode.

Please identify the make/model of furnace and thermostat and we can probably be more specific.

 

[Atthelake]

If the heater has been off - it's exchange chamber is filled with cooled air. So, if you turn on the fan (not to auto) the fan will push that cold air into the room - and will continue to do so until you turn it off. The moving air on your skin will also evaporate any moisture, making you feel cold.

The AUTO position of the fan switch means the fan will ONLY come on when the heater is heating (as set by the temperature control). When the heater does kick on you will get some cold draft as the fan starts and pushes out the un-warmed air, however as soon as the heater ignites it will turn to warm very quickly.

This is pretty much the same as many HVAC systems in a sticks and bricks home.

Don't listen to your salesman.

Thank you! Dealer is saying the furnace should only run on Auto and the ON switch is just for the A/C unit. Again the furnace ignites but just not pushing much heat..? Wondering if it’ might be the fan itself?

 

[Atthelake]

I'll concur with Domo's explanation. FAN ON means exactly that - the fan runs whether the furnace is hot or cold, so you are going to get cool air part of the time.

In general, the furnace burner should still heat (or not) in response to the thermostat set temperature, regardless of the Fan mode. However, for safety reasons a forced air furnace won't heat unless the fan is running to circulate the heated air, so it's possible your thermostat doesn't send the "Heat Needed" signal when the fan is in a manual control mode.

Please identify the make/model of furnace and thermostat and we can probably be more specific.

Thank you! I will have to get that info. I am a few hours away from the lake so when I go up next week I will grab that info. Thanks again

 

[Atthelake]

So does the furnace fire when room temp is below thermostat set temp? I can see that the fan would stay on when the thermostat is ON but would expect that a call for heat would also fire the burner. My S&B furnace operates this way. Sometimes I'll turn the fan ON to equalize the temperature in the house when DW is cooking full bore in the kitchen. Looking at the installation/technical data for the furnace unit should describe the modes and what thermostat connections are needed for it to operate.

Mark B.
Albuquerque, NM

Yes it fires just don’t push enough heat. Almost like the fan doesn’t work

 

[Kirk]

Please identify the make/model of furnace and thermostat and we can probably be more specific.

We need to know this to be sure that what you have is an RV type of furnace as not all park models have one and they operate somewhat differently from many of the other types.

Yes it fires just don’t push enough heat. Almost like the fan doesn’t work

As well as the make & model information, you might also post a picture of the thermostat.