How to Replace Spa Heater Tube

Balboa Spa Packs

Note that when the hot tub heater element has failed, the entire heater tube, including the temperature sensors, is swapped out.  Balboa does not sell the heater element alone.  However if one of the sensors is faulty, it only is replaced.  In either case, the replacement the entire Balboa heater tube needs to be removed from the spa pack.  Here is how you do it:

1) Close the two ball valves to isolate the heater from the hot tub.  Open the drain bib valve to drain the water that is between the ball valves.  This requires also opening the small black vent screw on top of the filter.  (you can use this opportunity to clean the filter if you wish).

2) Use two open ended crescent wrenches and remove the nuts that hold each copper strip to the heater element stud and then pull each copper strip back. The 2nd wrench attaches to the back nut of the stud and you hold it fixed so the stud wire does not get twisted.

3) Use a 3/8" socket wrench or open ended crescent wrench to remove the two nuts that physically secure the stainless steel tube to the spa pack case. 

4) Unplug the two temperature sensors from the SenA and SenB receptacles of the circuit board.  They have a little clip that needs to be pushed in to get them out.

5) Uncouple both PVC unions at the both ends of the heater tube.  This may require a strong wrist action if it is tight or you may even have to use of some other way to loosen these, if they are on very tight. Loosening the female nut requires a CCW rotation.

6) Now you can remove the entire heater tube assembly.  If you are replacing it with a new one, install the new one in reverse order. Left sensor plugs into SenA receptacle. 

7) If you are replacing only one or both of the sensors, first unscrew the black sensor nut and then remove the sensor(s). In some instances to remove the sensor, you may also have to push from the inside using some leaver device that you improvise.  Then install the new sensor(s), ensuring the O-ring is present, and reinstall the heater tube assembly in reverse to above.

Dieter Jung

Northern Lights Cedar Tubs Inc.

13/3/2013