CanadianSpaTech

Personally I'm buying a new one. Heaters are a wear item and that one looks pretty worn. How old is it?

First post photos of the board and the schematic on the inside cover. Remove filters. Next disconnect pump 2 from the board and see if it will run and heat. Use a multi meter and with #2 pump disconnected test for power going to the pump off the board when you engage pump 2. Test where the white and black wires connect. If you get power off the board then power down and reconnect. If it trips you likely have a bad pump. If it still trips with pump 2 disconnected then start eliminating the other components in the spa one at a time until the breaker holds. Post pics and results.

Post photos of the current board and how it is wired.

Where are you located? It can be repaired... I use a local Electronics repair guy. As for why... If the incoming power copper strand wires (or even worse aluminum strand) are not tightened enough to compress the stands it can come loose over time and arc leading to meltdown. I often have electricians (and homeowners) tighten the screws with their cordless drill and not go back over each screw (2x) and tighten by hand. They gotta be tight.

Have not seen that pump before but looks like it would work.

Try this first. https://hottubchemicals.ca/products/spaboss-ultra-spa Unlikely an option

Disconnect the heater from the board and test for 240V coming off the board when the heat indicator light is lit on the topside. If you gat 240V you likely have a bad heater element. Test the 2 wires for continuity. If you don't then it's a board issue and likely a blown relay. Relays can be replaced fairly cheap. I normally have my electronics repair guy replace all the relays while it is out.

Post photos of the circuit board so we can see.

Looks like a compression fit jet body. Starting to see these more and more and can see they will be problems going forward. Have not found available parts yet... but have not searched very hard. My way to go.... Remove the jet from the jet body. Marine grade silicone bead around the jet body and the acrylic where the o-ring gasket sits. Create a barrier and see if it holds. If no it looks like the jet body can be pushed forward into the bather area. Not cutting the plumbing lines. If you can push it forward far enough to get at the gasket o-ring you could replace the gasket if you can find one or... take a second shot at silicone and use the same gasket. The blue Loctite type stuff is glue and you won't get the hose off the jet body without cutting it and reattaching it once the repair has been made. Hopefully they left enough spare 3/4" hose to reach back to the jet body again. Glue I use: https://www.amazon.com/Weldon-10850-Medium-Bodied-Professional-Industrial-Grade/dp/B009YA250U

Regular 50 inside panel and 50 amp GFCI out by the spa. In view of the spa but no closer than 10' to the spa (check your local regs.) You should not be able to reach the GFCI from inside the spa bather area. You could put the GFCI in the panel and have a pull type disconnect outside but I find that those pull disconnects will sometimes trip the GFCI when pulled and if you don't have access to the inside you pack up your tools and go to the next job... ie Home...lol Solid advice How many amp does this draw? Don't max out the sub panel

If you are talking about TB1 where the incoming power wires connect to the board the white wire goes into #4. #4 is at the top, Then an open #1 then #2 red and finally #3 black at the bottom. FYI...Group #4 is just above where the incoming wires connect (J45), Group 2,3 are below it. Think you are a bit confused and thinking where the incoming wires connect to the board (TB1) are a "Group" They are not considered a "Group". Again Group #4 is above those incoming wire connections (J45 to J79 and for 120V) Group # 2 is below the incoming power wires J1 to J72 and is for 240V components. There should only be white wires connected at Group # 2.

Group 4 is for 120V components. If say you had a 120v ozone installed in the spa on most packs you would move the white wire from Group 2 up to group 4. Group 2 is for 240V components. So if you have any components that are 120V in the spa they won't work with this pack. I have never noticed or seen that a BP7 pack is 240V only. Odd they have dotted lines denoting 120V set up on the schematic.

Ouch... That's worse then Edmonton...lol. Good Luck in your search.

Where are you located?

#1 rule for buying a used hot tub... Never buy a hot tub you don't see running and up to temp. Don't be mad if it has issues. You've been warned.

Correct So bad relay?... Could remove board and look on back for darkened or burnt relay Odd... what size breaker do you have and is the spa wired 120V or 240V? Running in low speed AND the relays are good and it is sending power to the heater it should heat fine/normal in low speed. Is this a new to you install? Has it ever run as it should at your location?

Would be better if you have some. How about a hand cart/dolly? Home Depot rental maybe?... or buy and return...lol. Lay down a moving blanket first to protect the acrylic if needed

Bring a strap or 2 and some cardboard wide as the spa is tall so the spa will sit with cardboard under the acrylic edge to the base. Lay the strap down and the cardboard on top. Stand the spa on the cardboard and wrap the strap (s) around the spa. Slide the spa on the cardboard.

One way to test if you can get at the back of the motor and remove the dust cap you will see a slot in the shaft of the motor. While the spa is humming and trying to start the pump in low speed use a flathead in the slot of the shaft and give it some help starting. If it starts up in low with help then likely a bad start cap.

Does it hum or make a hard loud buzzing sound? Hum likely a bad cap. Loud hard buzz it could be a stuck relay sending power to both speeds at the same time. You are able to run in low speed after going into high speed so I don't think you have a bad relay. One way to test if you can get at the back of the motor and remove the dust cap you will see a slot in the shaft of the motor. While the spa is trying to start the pump in low speed use a flathead in the slot of the shaft and give it some help starting. If it starts up in low with help then likely a bad cap.

YouTube search: spa pump capacitor test

Unlikely. Coast does not use a traditional "Name" system to identify models. Try and search for Coast Spas and see if you can find a match and go from there. FYI if you are trying to find an owners manual you should be able to find on their website but there is very little useful information is most manuals.

Likely the spa is in "Rest" mode and should be in "Ready" mode. Should also be in "High Range". See page 39 here: https://www.masterspas.com/documents/_manuals/twilight/2015-twilight-owners-manual.pdf

Disconnect the pump from the board and test for low speed power off the board. If the board is sending correct power to the motor (in both speeds) then at this point I am replacing the unit. It could be cap related or possibly the hi/low switch in the back of the motor is faulty.

Likely a bad start capacitor on the motor.