On various retail sites, I usually see questions about small electric shop heaters (17000-19000 BTUs). Since the heater hangs from the ceiling, there are questions of how to easily control it without "setting and forgetting" or using a ladder.
I installed a 240V, 21 amp heater that is rated at 17,000 btu. It is wired with 10/2 with ground. I purchased a 240 V, 30 amp relay with 24 v coils. I then matched to that a 120V transformer with output of 24V. My third purchase was an adjustable wall thermostat rated for 24V. From the transformer I ran thermostat wiring to the thermostat and from it to the relay coils. The 10/2 runs from the panel to relay then to heater. I can easily set the thermostat and it cycles on and off. When I leave my shop, I turn the thermostat from "heat" to "off". Works great. I left out some wire routing details. If you aren't sure, seek help.
I installed a 240V, 21 amp heater that is rated at 17,000 btu. It is wired with 10/2 with ground. I purchased a 240 V, 30 amp relay with 24 v coils. I then matched to that a 120V transformer with output of 24V. My third purchase was an adjustable wall thermostat rated for 24V. From the transformer I ran thermostat wiring to the thermostat and from it to the relay coils. The 10/2 runs from the panel to relay then to heater. I can easily set the thermostat and it cycles on and off. When I leave my shop, I turn the thermostat from "heat" to "off". Works great. I left out some wire routing details. If you aren't sure, seek help.
