Good Day. We've just installed a wood gasifier into home. House has got a standard thermostat that runs AC and then has a 10K electric backup should the gasifier go down/vacation etc. Right now we have a small circ pump feeding a hot water loop to the furnace. It has it's own thermostat which triggers a relay that switches the pump. What we're trying to accomplish is getting the air handler fan to kick on when the pump does, without affecting the existing wiring from the original thermostat that current would turn on the electric backup when it's calling for heat. Right now they just run the airhandler fan full time, and when the gasifier thermostat calls for heat, it switches on the pump therefore sending hot water to the coil. Anyhow, your help would be appreciated.