How I Go from this old system....
To this awesome looking digital spa control installation in about 3 to 5 hours. Mistakes, the mess and trials and errors included....
First thing to do, start removing old equipment and cutting out the old plumbing. This is a no-brainer, simply remove all spa equipment and controller components - and make it viable for new heater plumbing. I prefer to use a "sawzall" or reciprocating saw to cut out things fast. This includes removing the thin wooden support in the middle of the spa (to the left of the blower) to make room for the controller. I cut EVERYTHING! Hoses, cables, the wood, pvc.. Takes only a minute or so.
Center wood support has been cut out. We're also going to be moving the old blower and hose (center-right side of photo) to the far right side of the spa cabinet, giving us a lot more space to work with. Here I've removed the fitting that connects to the Vulcan heater - note the Jacuzzi swivel fitting above the box - Going to remove the old control box from the metal support plate in a sec...
I love these saws on the job, make things go so much faster. Here I'm sawing off the pvc elbow that leaves the top discharge fitting of the pump. By the way, if you decide to use an electric saw to cut things like this, be sure the blade is at least 12 TPI, or made for metal/fiber cutting. NEVER use a WOOD blade! So far this is looking like a simple installation, provided however Murphy doesn't show up!
Left side of heater fitting sawed off from pump, right side of heater loosened now the old Vucan spa heater assembly is removed.. Next I'll saw off the old flow switch T to the right of this.. (Far right of photo at edge you'll see the top part of the flow switch and cord which is going away)
This looks better as time goes on, now just a couple of screws on the top of the control box to remove and it's gone. Old flow switch assembly is gone, Just the pvc elbow on the top right of this photo. I don't like to go too fast sawing out old plumbing until I'm 100% sure it's what I want to do. You'll notice the electrical 'victims' hanging loose from the old control box - that's the black wires that got cut off with the saw too... " title="Smile" />
Ok, as it worked out, there's about 3" of 1.5 inch pvc pipe extruding from the slicer valve, just before it went into the elbow that attached to the old flow switch. After this is done, then we go into the trial and error phase of putting the new spa control system in place to see exactly how the pipes and fittings need to be plumbed so it'll work right.
You'll notice the 2.5 inches of pvc pipe sticking out of the pump discharge fitting waiting to go back into action --- First though I'm going to remove the old top side spa control thermostat sensor from the thermowell. Easy to do, just loosen the plastic outer nut that holds the thermowell assembly in place, pull out the thermostat sensor and reassemble the thermowell so it won't leak.
With all of that out of the way now, I've got a couple of extra 45 degree elbows with me so I put them together, and install them on top of the pump. Simple.
Installed and positioned... A 4 inch length of 1.5" diameter pvc pipe connects both 45's to make an offset 90.
Hmmm, well this seems ok for a new installation but it's certainly looking a little 'tighter' than I would've wanted. The distance between the pump discharge on the left and the spa filter input (at the slicer valve) on the right isn't a whole lot.
It seems like everytime I think it's going to be a quick spa control installation, something doesn't go right. First, the left side of the new spa heater is right up against the thermowell housing, which is the tail end of a 1.5 inch pvc Tee. Second, the right side of the new spa heater is going past the input point for the slicer valve to the spa filter.
Here you'll see what I'm talking about. The red arrow on the left is pointing to the interference problem that I'm having with the spa heater fitting. On the right, to make matters worse, the discharge from the heater is creating an unacceptable angle in alignment with the spa heater discharge fitting. Everything under this spa has to be moved somewhere else for this to work properly.

More to follow, stay tuned...