SECTION 17: S
EQUENCE
OF
O
PERATION
53
Selectrastat dial. The 7-day programmable
to
u
chscreen thermostat pro
v
ides nighttime setback
for
u
nocc
u
pied space heating.
AUTO/WINTER Mode:
Occ
u
pied time: Blo
w
er and b
u
rner cycle operate
contin
u
o
u
sly to maintain a constant space
temperat
u
re as selected on the Selectrastat dial. The
b
u
rner flame f
u
lly mod
u
lates and
v
aries the
discharge air temperat
u
re to maintain the space
temperat
u
re.
Unocc
u
pied time: Blo
w
er and b
u
rner cycle on and off
to maintain space temperat
u
re as selected on the
to
u
chscreen thermostat (night setback).
ON/WINTER Mode:
Blo
w
er and b
u
rner operate contin
u
o
u
sly to maintain
a constant space temperat
u
re as selected on the
Selectrastat dial. The b
u
rner flame mod
u
lates and
v
aries the discharge air temperat
u
re to maintain the
space temperat
u
re.
ON/SUMMER Mode:
Only the blo
w
er operates contin
u
o
u
sly to pro
v
ide
u
nheated air. The b
u
rner remains off regardless of
temperat
u
res on the temperat
u
re selection dial and
thermostat.
FAN ON indicator:
Indicates that the air handler is s
u
pplying po
w
er to
the blo
w
er motor
v
ia the M1 motor starter.
BURNER ON indicator:
Indicates that the air handler has s
u
pplied po
w
er to
open the main gas safety sh
u
t off
v
al
v
e.
BURNER LOCKOUT indicator:
The b
u
rner control mod
u
le has experienced a fa
u
lt
and
w
ill need to be reset. The b
u
rner control mod
u
le
m
u
st be reset at the air handler. Refer to
Page 72,
Section 21
and
Page 82, Section 23
to determine the
ca
u
se of the fa
u
lt.
CHECK FILTER indicator:
The airflo
w
in the air handler is ins
u
fficient to acti
v
ate
the lo
w
press
u
re s
w
itch. This is most commonly
ca
u
sed by dirty filters b
u
t co
u
ld also indicate other
obstr
u
ctions in the air stream.
