Rheem 834 Series Service Instructions Manual page 58

Overheat Switch (Procedure 21)
1. Isolate water supply to heater by closing cold water inlet isolation valve located
below heater.
2. Remove front panel by following steps 1 ~ 2 of procedure 1.
3. Disconnect wiring from overheat switch.
4. Remove two Phillips head screws retaining overheat switch and remove switch.
5. Reassemble in reverse order of above.
Heat Exchanger Assembly (Procedure 22)
1. Isolate water supply to heater by closing cold water inlet isolation valve located
below heater.
2. Isolate gas supply to heater by closing gas isolation valve located below heater.
3. Remove front panel by following steps 1 ~ 2 of procedure 1.
4. Relieve system pressure by opening and then closing a hot tap, then disconnect
plumbing from water inlet and water outlet connections and allow heater to drain.
5. Disconnect plumbing from gas inlet connection.
6. After heater has drained, remove heater from wall by lifting heater up from rear
mounting screws.
7. Remove five Phillips head screws retaining flue collector / flue terminal assembly to
heater surround panel.
8. Remove two Phillips head screws retaining flue collector / flue terminal assembly fixing
brackets to heater rear (located inside heater rear at left and right sides).
9. Remove two Phillips head screws retaining flue collector / flue terminal assembly to
front of copper heat exchanger and lift flue collector / flue terminal assembly out from
heater.
10. Remove two Phillips head screws retaining overheat switch to heat exchanger pipe
work and move overheat switch out of the way.
11. Remove clamp from heat exchanger cold water inlet pipe and pull pipe out from heat
exchanger (be careful not to lose pipe o'ring).
12. Remove clamp from heat exchanger hot water outlet pipe and pull pipe out from heat
exchanger (be careful not to lose pipe o'ring).
13. Remove two Phillips head screws retaining heat exchanger front mounting brackets to
front of burner assembly.
14. Remove two Phillips head screws retaining heat exchanger rear mounting brackets to
heater rear (located inside heater rear at left and right sides) and lift heat exchanger
out from heater.
15. Reassemble in reverse order of above ensuring o'rings are clean, free from cracks and
lubricated with silicone grease if dry.
16. Start heater and check for water leaks.
17. Purge air from premises hot taps.
TM081 Rheem 834 Series Hydroelectric CFGWH Service Instructions
REV: AA Issued: 22/02/17
This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed uncontrolled.
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