CanadianSpaTech

Little red box just below where the light connects to the board. Turn power off to move switch A7 to up position. A1 is on left end A10 is on right end

In sleep it will only get to 80 degrees. There may be a setting on the circuit board to change the topside mode settings from SL/ECN/ST to just Standard mode. Then if the buttons still work you would be able to press the up button a bunch of times and see it you can get it up to 104 and then each down temp button press will equal 1 degree. Not perfect but might work for now. Post picks of circuit board and the schematic on the inside cover and we can see if there is a "dip" switch setting you can make to get it to ST mode only.

Likely yes if you have no led numbers showing. Should still heat though. Pop the topside out and the part number is on the underside. Make sure to match the button configuration when ordering.

Marine grade Silicone around the jets where the jet body meets the acrylic. Otherwise you will have to remove/disconnect the pumps and pack and then stand the spa up and remove the bottom to be able to fix from the inside of the cabinet.

High fail rate on those topsides

Doesn't have to be Devcon. Should be able to find a suitable epoxy at your local hardware store

hard plastic/acrylic and Devcon 2 part plastic weld epoxy

Yes

Spray all surfaces down with a mold inhibitor spray... https://www.homedepot.ca/product/concrobium-mold-control-spray-bottle-946-ml/1000150815?eid=PS_GOOGLE_D00 - E-Comm_GGL_Shopping_PLA_EN_All Products_All Products__PRODUCT_GROUP_pla-294971530742&gclid=Cj0KCQjw4NujBhC5ARIsAF4Iv6dgByALlxv3pA3BQRUE_1Kece428IhsUuulMwTlfbM9jMG_UET1mZUaApNIEALw_wcB&gclsrc=aw.ds

https://www.poolspaforum.com/forum/index.php?/topic/55652-hot-error-code/

remove the plastic nut and lay silicone to it

Yes they work well and are used on most systems Could very well be. Could it be a worn O-Ring on the face plate?

Test all fuses. Is there an AUX button? Some spas the pump button works both pumps progressively. First press pump 1 low speed, second press pump 1 high speed, 3rd press pump 2 high speed.. or low then high if pump 2 is a 2 speed pump. If fuses all test good you might have to disconnect pump 2 from the board and test for power coming off the board when pump 2 should be running. If you get power then it is a pump issue if you don't then it is a board issue and possible bad relay.

https://www.poolandhottubdepot.com/5hp-impeller-for-waterway-coast-spas-14a-franklin-motors-only/

@B Land Yes standing the spa and removing the bottom might be your best option. What is on the other side of the elbow? You will have to get to the other side of it and get to either soft plumbing or to wherever the rigid plumbing ends and that might be a fitting that enters the bather area. Post more photos once you get to the other side and we can advise you from there.