How Propane Heaters Work
Propane hot tub heaters use liquid propane as a heat source, burning it in the same manner as propane home heating systems or in-line propane water heaters. The burning propane heats water as it passes through copper tubes, the natural expansion of water as it heats causing the water to circulate and provide hot water for the hot tub. The displacement of water by the expanded hot water drives water back into the pipes to be heated, creating a water heating cycle for the hot tub without the need for an electric pump.
Propane hot tub heaters offer several advantages to hot tub owners. Because propane heaters generate their own water circulation, they can place the hot tub in locations where electricity is not readily available. The propane heaters are energy efficient, heat the water in the hot tub significantly faster than electric heaters and lose less heat to the air while bringing the hot tub to the desired temperature. If you already have a propane tank for heating your home you can run your hot tub off the same source of propane.
A professional should install a propane hot tub heater. The propane line needs to run by your propane provider and will likely run underground to protect it. The heater itself will sit on a flat, level surface next to the hot tub. If the hot tub doesn't have a suitable area next to it, the professional will create an appropriately-sized foundation made of a solid material such as brick or concrete.
Propane hot tub heaters have few if any moving parts and as such require relatively little maintenance. You should have the connection to the propane line checked yearly when getting your propane tank refilled to ensure that there are no leaks. Perform periodic checking of the burners to make sure that they are all burning correctly.
Winterize the heater and hot tub to prevent water from freezing inside of the unit or the hot tub should be drained completely if you don't plan on using it during the winter. If you notice any leaks or signs of damage, call a repair technician to inspect the heater.