Specifications
TM040 16, 18 & 20L Continuous Flow Gas Water Heater Service Instructions
D.O.I: 2/06/2009
This document is stored and maintained electronically by Service. All printed copies not bearing this statement in RED are deemed “uncontrolled”
54
Over Heat Limiter
Replacement of the Over Heat Limiter requires removal and possible replacement of the
Heat Exchanger.
1. Remove the Heat Exchanger. Refer „Heat Exchanger Removal‟ procedure on page 52.
2. Remove the two white wires from the terminal block on the right hand side of the Over
Heat Limiter.
3. Remove the two plastic rivets retaining the Over Heat Limiter to the back of the water
heater cabinet and remove the Over Heat Limiter.
4. Inspect the Heat Exchanger for holes or combustion damage. (Replace Heat
Exchanger if necessary)
5. Reassemble in reverse order of above (Note: Ensure all multi-pin plugs are
reconnected and all wiring is neatly repositioned and retained to prevent damage
during operation).
6. Test operation of water heater.
7. Check and if necessary adjust the MIN and MAX burner gas pressures. Refer to
„Burner Gas Pressure Check‟ procedure on page 46 and „Burner Gas Pressure
Adjustment‟ procedure on page 47.
Controller
1. Isolate power at the water heater.
2. Remove the small Phillips head screw from the bottom of the Controller.
3. Gently pivot the Controller up from the bottom and then lift up and off upper retaining
lugs.
4. Kitchen Controller: Disconnect the wiring from the terminals on the back of the
Controller (Note: The wiring is not polarity sensitive).
Bathroom Controllers: Disconnect the multi-pin plug.
5. Reassemble in reverse order of above.
Transformer
1. Remove the Front Panel. Refer to „Front Panel‟ procedure on page 48.
2. Disconnect the Transformer secondary windings from the bottom right hand side of the
PCB (2 x red wires).
3. Disconnect the multi-pin plug to the Transformer.
4. Remove the four outside screws on the underside of the water heater retaining the
Transformer base to the water heater cabinet.
5. Lower the Transformer and base plate from the base of the water heater.
6. Remove two screws retaining Transformer to the transformer base plate.
7. Reassemble in reverse order of above.