Carrier 58MVP - Manual (Page 4)

b. R-W/W1 with R-Y/Y2 and R-G signals terminated—
The blower continues to operate completing a normal
blower off delay.
11. Post purge—The inducer continues operating for 15 sec after
gas valve is de-energized.
Step 7—Continuous Fan Mode
1. Operating with continuous fan only.
a. Call for continuous fan—The thermostat closes R-G
circuit.
b. Blower on—The blower starts immediately.
NOTE: The blower starts at approximately 400-500 RPM. After
20 sec, the motor is turned off for 1/10 of a sec where a coast down
calibration is done to evaluate resistance of the conditioned air
duct system. The microprocessor then determines blower RPM
required to provide proper airflow for heating mode.
NOTE: The continuous fan speed is the same as low-heat speed
unless it is field adjusted to another desired airflow. See Continu-
ous Fan Setup Switches section in Installation, Start-Up, and
Operating Instructions for details. There is also a chart on
schematic diagram shown in Appendix A.
c. Electronic Air Cleaner—The EAC-1 terminal is ener-
gized whenever blower operates, regardless of operating
mode.
2. Operating with continuous fan (R-G) and call for heat
(R-W/W1) is received—Same as heat pump mode except
blower on delay is 10 sec less than the heat mode. After call
for heat (R-W/W1) is terminated, the blower remains operat-
ing at low-heat speed for selected blower off delay before
resuming continuous fan speed.
3. Operating with continuous fan (R-G) and call for cooling
(R-Y/Y2) is received—See Cooling Mode section. After call
for cooling (R-Y/Y2) is terminated, the blower remains
operating at cooling speed for 90 sec before resuming con-
tinuous fan speed.
Step 8—Component Test
All components are functionally operated except gas valve with
component test feature.
This feature helps diagnose a system problem in case of a
component failure.
NOTE: Setup switch SW-1 MUST be in OFF position or Fault
Code 22 (setup error) will occur.
NOTE: NO thermostat signal may be present at control center,
and all blower time delay off periods must be completed.
To initiate component test feature, proceed with the following:
1. Leave 115-v power to furnace turned on.
2. Remove main furnace door.
3. Remove blower access panel.
4. Turn setup switch SW-6 to ON position.
5. Manually close blower access panel door switch.
On some models, blower access panel door switch opens only
24-v power to control center. No component operation can
occur. The 115-v power is still present at control center,
transformer, inducer motor, and main blower motor. Caution
must be taken when manually closing this switch for service
purposes. Failure to follow this warning could result in
personal injury or death.
Fig. 1—Variable Speed Furnace Control
A98293
SEC-2 SEC-1
W2
Com 24V
W/W1
Y/Y2
HUM
RG
DEHUM
SEC-2 SEC-1
DE
W2
Com 24V
W/W1
Y/Y2
HUM
RG
DEHUM
DE CONNECTION
WITHOUT DE
CONNECTION
WITH DE
CONNECTION
4