cranbiz

@CanadianSpaTech I believe you mean 750W setting, not 750V. Not sure I want to see the aftermath of setting the heater to 750V. 🔥🔥🔥🚒

It should unplug from the main board. You will need to pull the side cover and the cover of the box the board is in. It will also be a good time to get pictures of the board and wiring as well as the wiring diagram which is usually on the inside of the spa electronics cover.

You will be better off doing 2 things here. 1) Start a new thread. In it be specific in your ask and in what you have done. You have posted your question in a thread that had it's last reply year ago. The experts will normally skip over old threads and even if they do stop in, they will not read the entire thread because someone brought it back to life and says their issue is the same. A new thread will get much more attention. 2) Post up pictures showing what you need. In this case, it wouldn't hurt to post up overall equipment area pictures too. Now this tube you need to replace, is it the heater tube or something off of it? As I said before, pictures will help here.

Post up pictures of the board and the wiring diagram that is usually found on the inside of the cover. Make sure we have a good shot of the dip switches. There are several jumper wires that need to be moved as well as changing dip switch positions. It's not hard to miss one.

You can use any pack that supports the features of your tub. If you have 2 pumps, circulation pump and ozone, that's the minimum number of features the pack needs to support,

The topside controller doesn't really help in this. You need the model number from the spa pack in the tub. The manual won't really tell you much either. They are not very detailed, basic wiring and operation is about the best you will get.

In the end of the pump there is a hole which you can access the pump shaft. Try to turn it with a screwdriver. Does it spin freely? Your pump also should have a centrifugal switch in it. Check that switch out, make sure the contacts are good and not carbon arced. Are you sure that you don't have a start cap as well as a run cap? Putting in a 45uf cap won't hurt it but also won't make any difference.

You should have 120v across the red and white pair the black and white pare and 240v across the red and black wires.

Sounds like a bad relay in the control board. The pump is probably fine. Post up pictures of the control board, the wiring diagram of the spa, which is usually on the back side of the cover and the pump wiring diagram on the pump.

Post up a picture of the wiring diagram which is usually found on the inside of the cover.

Bad circulation pump. Not an uncommon occurrence.

To me, everything revolves around the circulation pump working correctly. Yours certainly appears bad. Circulation pumps go bad way more frequently than any other pump.

Do you get good flow out of it? It's very common for the circulation pump impeller to go bad.

$6000 for a trailer just to move a hot tub doesn't sound very budget friendly to me. Now, if one has other uses for a trailer like that, sure. Will you need the trailer on the farm as well as using it to move a tub? If so, then yes, an equipment trailer will work. You may need to add cribbing as many large tubs are wider than many car trailer decks.

Hot Springs doesn't release those to anyone except authorized dealers. Post up your problem with pictures of the plumbing, control box, wiring diagram and equipment area. The more info you can give us, the better the results normally are.

Those caps look good (well, the left 3 do, hard to tell if the right one is domed from this angle). A bad one will have a domed top and possibly electrolyte leaking from it. If the right one is domed, then it's bad and can be causing issues.

This one is close enough. it's a 4HP 2 speed pump. Your current pump is a 4.5hp +- 1/2HP https://www.amazon.com/2-Speed-Waterway-Discharge-Executive-3721621-13/dp/B00KYPVF50

Sounds like it's air bound. You sure you bled all the air out of the lines?

I used a couple of big electrical reducing washers. If I remember right I needed an 1 1/4 to 1" and then a 1" to 3/4". You could also buy a zinc 3/4" flange, attach it to the tub side and thread the liquidtite elbow into it

Flow switch shouldn't matter. It's an off-on switch. Polarity doesn't exits on those.

Is the tub keeping the set temperature? If so, you are good. The pump is cycling as it's supposed to. Most owners manuals are crap and really don't explain the full operation of the tub.

Depending on how it's plumbed, it may only turn on to get the tub back to the set temperature. When you did a drain and refill, the tub was coming back up to temp so the circulation pump would run. Once up to temp, it will only run when the tub drops below the minimum temp range to bring the tub back up to temp.

Check the heater element. With an ohm meter, check the resistance of the heater. It should be between 12-18 ohms. You can also check that the heater is getting voltage when the tub is calling for heat. There should be 220V across the 2 heater terminals. (assuming you have a 220V tub)

The blue disc is a MOV, or also known as a surge protector. Looks like a lightning strike near by.

Yes, the yellow stuff is just glue/potting compound. There is a good chance that the power supply board is bad though. It's a common problem.