Hot tub heater making a funny sound, what do I need to do?

See if turning down the temperature stops the buzzing sound. If so, then the heater relay is probably failing, happens all the time. There are several circuits in the hot tub, most are for the air-jets, but the heater circuit is the most punished. A lot is demanded of it, and I would say as much as 90% of the electrical power pulled by a hot tub goes through the heater circuit. I'd recommend finding a replacement circuit board ASAP or learn to fix your own (de-solder the broken relay and install a replacement...preferably with the power OFF!).

One more note: you mentioned it was drained. I hope it wasn't turned on while it was drained, cuz that will run the water pumps with air in them, which is almost always a bad idea (it will burn out the pumps), plus the heater probably won't like it, either (the element will burn out or melt)

If this an electric powered Heater, this is maximum probable the heating factor lengthy gone out. They less then $10 at Lowe's/homestead Depot. Be very certain the electric powered to the heater is off. eliminate the metal panel, if there one staggering and backside, be taught the staggering first. maximum probable at an identical time as the pipes were re-artwork the water point pass down interior the heater (Siphon consequence) and the staggering factor overheat and burn out. you will possibly prefer to be taught the two. Use a backyard hose to empty the heater. as soon as it fix, make certain you fill nicely with water previously turning the electric powered back directly to the heater, allow it set for air to settle and top off, try this by utilising turning on a warm water faucet.. additionally, i could use a Volt Meter to make certain the electric powered is off, regardless of what the Breaker field say. One solid factor about experts, they make blunders too! ;-)