central heat question

[stltreedr]

Im running an OWB with a heat exchanger on the central unit. It usually keeps the house comfortable, but in this extremely cold weather ive noticed that it cant keep up. When the propane furnace does come on, the volume of air coming out of the vents seems much greater, almost like the fan is in a "higher gear" for lack of a better term. Any ideas?

 

[OH_Varmntr]

Is your blower motor wired separately for your wood heat and propane heat? Most blower motors have multiple taps to control the speed of the motor for different operations (air conditioning vs heat).

Heat usually is setup to blow slower than air conditioning, but maybe whoever wired it up did so that the your wood heat is set lower than your propane heater. If you have central air conditioning then I'm assuming that's what it is considering there's usually 3 sets of taps and the wood heat would be the last unused tap. For example, Air Conditioner has the High speed, Propane is Medium speed, and your wood heat is Low speed.

 

[stltreedr]

a friend and i wired the thermostat trying to follow the directions. we never messed with the wiring on the motor itself
Can this mistake be made on the thermostat or on the thermostat controls on the furnace? Yes I do have central air. Anywhere I can find a diagram of the different taps you're speaking of?

 

[OH_Varmntr]

Most multi-speed blower motors have White (Neutral), Red (Low Speed), Blue (Medium Speed), and Black (High Speed) wires. I'm assuming you have a blower control board that changes the speed of the motor depending upon which thermostat tells it to turn on. The motor wires will go to that board, which is where the mistake could have been made, yes.

Have you stood by the blower when it cycles between wood heat and propane heat? You should be able to hear the speeds change.

 

[stltreedr]

I will check all that out tonight.. Thanks for all your help.