This process is used on Dimension One Spas with a “Trombone” style heater from 1998-2014. The photo shows a typical example of the equipment layout for a 2-pump system.
You’ll need to shut off power at the GFI and drain the spa to get started.
Cut the zip tie holding the High Limit Sensor in place. (Fig 1a)
Slide the High Limit Sensor out from under the pad. (Fig 1b)
Unplug the flow switch connector from the PC Board. Please call us if you need help locating this connector.
Cut the 4 heater wires where they enter the metal equipment box. (Fig 5a)
Disconnect and remove the wires you’ve just cut.
Unscrew and remove the thin nut holding the plastic heater box to the metal equipment box. (Fig 5b)
Loosen and slide the clamp to the right of the flow switch. (It only needs to move about 1 ½”.)
Separate the flow switch from the hose.
The heater assembly is now loose and can be removed. You’ll have to be a little creative and use some muscle to get the assembly out. Just be patient and you’ll figure something out.
The new heater has an adapter that you won’t need for this installation. Remove and dispose of the adapter.
Attach the new heater wires to the circuit board. (Fig 17a)
Attach the ground wire to the grounding nut inside the metal box. (Fig 17b)
Remove the nylon clamp holding the hose in place.(Fig 2a)
Remove the metal bracket holding the heater tube in place. (Fig 2b) You won’t need to replace this metal clamp later. The heater will stay in place without it.
Remove the wire between the heater lug and grounding lug. (Fig 6a)
Remove heater grounding wire at grounding screw. (Fig 6b)
Loosen hose clamp where lower heater hose attaches to the circulation pump. (The middle of this pump can be red, blue or black).
Set the old heater next to the new heater as pictured.
Move the short piece of hose from the bottom of the old heater tube, to the new heater.
Attach the new flow switch tee to the old hose. (Fig 14a & 14b) Slide the hose clamp back to the left and back in place. (Fig 14c)
The grounding lug on the new heater tube is in a different position so we’ll have to make our own new ground wire to attach outside the box. Taking the original green wire from the old heater, cut a piece 6” long. Remove about ¾” of insulation from each end, (Fig 18a), and twist the wire strands.
Attach one end onto the heater lug and the other on the grounding bar as pictured, (Fig 18b).