Error Code 99 / Warning Code 10 - Rheem 862 27 Series Service Instructions Manual

Error Code 99 / Warning Code 10

Fan Motor is not creating enough ventilation. The fluing system passed pre-purge, but has
failed during normal operation. At a minimum check the following:
1 Check for blockage of heat exchanger fins.
2 Check heat exchanger flapper valve at vent connection of water heater moves freely.
3 Clean air intake filter.
4 Remove all obstructions. Check the flue termination on the outside of the building and
the flapper valve at the top of the heat exchanger.
5 Temporarily disconnect the flue structure from the water heater. If this fixes the problem,
then the issue lies in the fluing. If this does not fix the problem, then the issue lies in the
fan motor or printed circuit board.
Warning Code P1
Water flow rate is less than minimum for main burner ignition. The unit must have 2.5 litres
per minute before the main burner will light or sustain burner. When water flow does not
reach minimum flow rate for five seconds the warning code is displayed. At a minimum check
the following:
1 Check cold water inlet strainer for debris.
2 Check fixture aerator strainer for debris.
Noisy Operation
Internal Models – As the unit is a room sealed heater the air supply for combustion is
delivered via the coaxial flue. Ensure that the correct Rheem approved coaxial fluing has
been fitted. If the Rheem approved coaxial flue is not fitted the unit may be starved of oxygen
and excessive vibration/noise will be generated.
TM049 27L Continuous Flow Service Instructions
REV AL – Issued April 2019
This document is stored and maintained electronically by Rheem Technical Support. All printed copies are deemed "uncontrolled".
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