The Sundance Spa has been making a low humming/buzzing noise on and off for the past few weeks. This noise is quiet in comparison to the gurgling noise the spa used to make before the circulation pump was replaced, but it’s still annoying.
The low frequency humming/buzzing noise was intermittent which made it all the more obvious as it came and went. It sounded like something was loose or vibrating within the spa.
I took off the front panels of the spa to isolate the noise, which turned out to be coming from the SunZone ozone generator. This device uses high intensity UV light to create ozone that is sucked into the circulation water supply to help with sanitation.
To try and get rid of the noise, I thought I’d see if anything was obviously loose in the generator. After turning off the power to the spa I removed the SunZone ozone generator which was only held on by 4 wood screws. On the back though, there were at least 12 metal screws, 3 bolts and 2 rivets. Too many things to make pulling it apart simple.
Onto plan B. I held the unit at various angles and gently thumped the unit with the base of my hand in the hope that if something were loose it would move enough that it wouldn’t vibrate any more. It was a bit of a long shot but it was worth a try.
After reinstalling and turning the power back on I was pleasantly surprised to not be hearing that annoying buzz anymore. Magic! Sometimes I get lucky.
While I was there I also zip-tied the hartford loop in the ozone air line up above water level. Previously it was just sitting on the top of the circuit board housing. Not sure if that had any affect on the noise.