Lennox MS8 SERIES Installation And Service Procedures page 77

OUTDOOR UNIT HIGH TEMPERATURE AND OVERLOAD PROTECTION
High temperature and
overload protection
Is the outdoor ambient
temperature higher than
127ºF (53ºC)?
Power off system and
restart after 20 minutes
Is heat dissipation of
indoor and outdoor units
abnormal?
N
N
Is outdoor unit fan
operating correctly?
Y
Replace outdoor
control
End
APPLICABLE UNIT SIZE(S): All
APPLICABLE ERROR CODE(S): E1, E5, H4
This is a normal protection
Y
feature of the unit. once
outdoor ambient air
temperature drops below 53ºC
(127ºF) system will operate.
Improve heat dissipation of
Y
environment around unit.
1. Check connection to OFAN
terminal on outdoor control.
1. Check resistance between
N
OFAN terminals, should be
1k ohm.
Replace C1 fan
capacitor
Replace
outdoor fan
FIGURE 86
Page 77
Corp. 1244-L9