We have a Hartell Automotic Condensate pump (KT-15X-1UL) attached to our Comfortmaker super high efficiency furnace/air conditioner. It is making a continuous racket. There is a powdery substance that fallen under the pump and there is a small hot smell coming from it. Can we safely unplug it till the repairperson arrives tomorrow or will we lose heat? Will we risk anything by not unplugging it?
Thanks!

If the pump is disabled, any condensate produced by the system will overflow the reservoir. Unless, the pump has an auxiliary/overflow switch wired to shut down the system and prevent overflow. It sounds like you are in the market for a new pump anyway, so perhaps get what you can from this one.