Balboa Metal Boxed M7 Heater Fitting & Removal Guide

Metal Box M7 Heater Fitting & Removal Guide

This M7 Balboa heater is usually mounted on the bottom of the spa control box, you can remove this heater without the removal of the control box. Do this by undoing the two large plumbing union collars first and if needed unscrew the two screws from the split heater collars and remove them completely to give you more space. Disconnect the two copper power terminal straps by removing the two 3/8" nuts and gently bend up the copper straps away from the terminals. The heater tube itself is held into the control box by two aluminium mounting brackets, remove these by unbolting the four 5/16 bolts that are secure the brackets to the control box. Unplug the two M7 sensors from the printed circuit board by pushing the small tab in and unclipping from the PCB. Remove the heater from the control box and reinstall in the same order.

Take care when tightening the two heater power wires onto the new heater terminals, use a 1/4 inch spanner and hold the base of the terminal whilst tightening the 3/8 inch nuts up to prevent the terminals being twisted. New gaskets are supplied with the new heater so replace and fit these to your heater union connections.