50 | P a g e S V C 8 2 0 ( P ) P o c k e t M a n u a l
50
Explanation: OHL (Over Heat Limiter) or Over Temp Limit
Switch activated. IF the OHL or Over Temp Limit Switch has
been activated, this is normally caused by inadequate/wrong
GAS SUPPLY and/or VENTING.
CHECK GAS SUPPLY & VENTING (refer to pages 8-11).
Diagnostic Checks:
OHL
High-Efficiency ONLY: Over Temp Limit
Switch (monitors vent temperature)
High-Efficiency Indoor (condensing) ONLY:
Locate the Over Temp Limit Switch (circled in red)
Connector Location
On Page 14
Turn Power OFF.
Remove & reinsert connector U.
Attempt to operate unit.
Does 14 – Error Code appear?
Continue to diagnostic chart
on next page.
YES
Unit had a loose connection
or over temp limit switch
cooled down. Unit appears
to be operating OK.
NO