cranbiz

Pictures of the filter area would be helpful.

The Cover Guy is one that gets mentioned here a lot.

110V or 220V? Pictures of the inside of the pack and of the wiring diagram in the inside cover along with the equipment area would help a lot.

No issues with leaving the stereo unplugged. I can't read the output voltage on the power supply so I really can't guess what else it may supply power to.

Have you checked the flow switch? If it isn't working correctly, you will get an OH indication.

Many low end tubs use the heat from the pumps to heat the water, so yes, it is a thing.

Honestly, I would replace those 2 relays and the jumper wire. The one closest to the burned end of the wire got hot. I suspect if you replace those relay's and the wire you will be good to go.

I see you have a second thread on this and said there is a burnt wire/trace. Go to that one about repairing the board.

If it's a relay, relays can be sourced from Amazon and replaced. If you can't solder, you should be able to find an electronics guy that can. I would replace them all while it's being done. New relays will refresh the board and in the overall scheme of things, are not expensive. If it's a trace on the board, that can be repaired with a piece of wire, simply jump between solid terminals that bridge the break.

Did you get 240V between the 2 heater terminals? I'll guess that you will but check anyways. If that is good, disconnect the power and then disconnect the heater from the board. Then check the element with an ohmmeter. You should see anywhere from 10-18 ohms on it. If you don't then you need a new element. I suspect your element is open.

The flow switch should be an off/on switch but sometimes they will get intermittent or crap in them which prevents the 0 ohm reading. For the temp/limit sensors, they should read in the 10's of K range and if you have multiple sensors they should be close to each other in their readings.

It could be the sensors or it could be the flow switch/sensor. I would test the sensors with an ohm meter first before just swapping out sensors.

First, I doubt your advice will be used by the OP, who was looking at hot tubs 6 years ago. Then we get into MasterSpa, their business practices and quality. MasterSpa makes an OK spa. It isn't a top tier spa. There is not anything outstanding about them. Hot Springs, Sundance, Artesian, Bullfrog, Marquis and Jacuzzi are far better tubs. The biggest issue with MasterSpa is that they use the travelling roadshow to sell tubs and then it's just about impossible to get warranty service (dealer are the ones to honor the warranty and the roadshow dealer really could care less about you once you fork over your cash). Do you work for a MasterSpa dealer? Sure sounds like it.

I would use the yellow simply because the Taylor kits use yellow and I trust the Taylor kits over others. In reality, as long as all give the same numbers then both should be reliable and you can use whichever kit you wish. Have you tested each with the same water sample? Same water, same results, then use whatever color costs less.

The T is glued in. A clamp can't properly secure that connection as the T is hard plastic over the soft flexible tubing. If the tubing was over the T, a clamp would work.