1.
(See Fig. 23 or 32 for thermostat connections)
NOTE: The
The furnace will start up in either low- or
If the power is interrupted, the stored history is erased and the control CPU will select
The wall thermostat “calls for heat”, closing the R to W circuit. The furnace control performs a
a. Inducer Prepurge Period
(1.) If the furnace control CPU selects
(2.) If the furnace control CPU selects
b.Igniter
c.
d.
e.
f.Switching from
g.Switching from High- to
h.
2.
NOTE: In this mode the LHT must be ON to select the
The wall thermostat “calls for heat”, closing the
The start up and shut down functions and delays described in item 1. above apply to the
58CT
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