On our 2015 159 HT EXT we ordered the rear heat / ac option with the idea of having an engine heated HWH. I'm thinking of a Isotherm SPA model in 4, 6.5 or 8 gallon size. I like the 750 watt heater as it will be manageable with a 2kw inverter and 460 ah battery pack if not running the engine.
I don't really know what the $96 package got us except for a pack of two 'T' fittings and clamps (pic). The 'T's are 3/4" x 3/4" x 3/8". My assumption is that they should be installed in the heater hoses near where they attach to the dash heater at the firewall (pic). My tank will be near the wheel well on the drivers side so I figure about 15' of hose each way (30' total). I'll probably go with 1/2" heater hose as 3/8" sounds pretty small for that run. I assume the flow will be adequate as it works for the dash heater. I'll install a ball valve to shut the system off if needed. Perhaps I should put a ball valve near each 'T' in case a tube would get damaged where they run underneath.
It doesn't look easy going underneath with the hoses, particularly from the firewall back to where the load floor starts. From there it looks like I can stay along the rocker panel pretty much. It would be great to go under my plywood floor (3/4" with 1" polyiso underneath) but I don't have a clue as to how to get in there from the front. I'll probably try to wrap some EZcool insulation around the hoses.
Has anyone installed this type of system yet? I read Seapro's post about his isotherm tank and he was concerned about warranty implications of an engine connection. I figure if they sell a rear heater kit it should be okay to install it. Of course I don't have any specific info from FCA on how to do it and the upfitter's guide doesn't address it.
I'd appreciate any thoughts on how to best go about this installation. Bill
I don't really know what the $96 package got us except for a pack of two 'T' fittings and clamps (pic). The 'T's are 3/4" x 3/4" x 3/8". My assumption is that they should be installed in the heater hoses near where they attach to the dash heater at the firewall (pic). My tank will be near the wheel well on the drivers side so I figure about 15' of hose each way (30' total). I'll probably go with 1/2" heater hose as 3/8" sounds pretty small for that run. I assume the flow will be adequate as it works for the dash heater. I'll install a ball valve to shut the system off if needed. Perhaps I should put a ball valve near each 'T' in case a tube would get damaged where they run underneath.
It doesn't look easy going underneath with the hoses, particularly from the firewall back to where the load floor starts. From there it looks like I can stay along the rocker panel pretty much. It would be great to go under my plywood floor (3/4" with 1" polyiso underneath) but I don't have a clue as to how to get in there from the front. I'll probably try to wrap some EZcool insulation around the hoses.
Has anyone installed this type of system yet? I read Seapro's post about his isotherm tank and he was concerned about warranty implications of an engine connection. I figure if they sell a rear heater kit it should be okay to install it. Of course I don't have any specific info from FCA on how to do it and the upfitter's guide doesn't address it.
I'd appreciate any thoughts on how to best go about this installation. Bill

