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There is an "insulation kit" available for HS spas?
Look at the inside of your motor compartment door - if if is covered by a black plastic panel, it is already insulated. there is not much insulation, only about a 1/2" think foam board, but combined with the door itself and the plastic inside panel, it should be fine. I think the insulation kits were for spas prior to this factory insulated door, which I just noticed around 2006 or so.However, if you think you need to add something, I would ask your dealer if they have had to do this for others in your area. 8-)
Can someone take a picture of the black plastic panel? I don't think I need one but I would like to see what it looks like.Thanks in advance............