Check Safety Controls - Payne C Series Installation, Start-Up, Operating, Service And Maintenance Instructions

Table 9—Speed Selection
COLOR
White
Black
Yellow†
Blue*
Red*
* 1/5 HP motor models: BLUE to HEAT, RED to SPARE.
† Not available on 1/5 HP motors.
NOTE: Continuous blower is the HEAT speed.
d. Turn thermostat down below room temperature and re-
move blower access door.
e. To change motor speed selection for heating, remove
blower motor lead from control HEAT terminal (See Fig.
24.) Select desired blower motor speed lead from one of the
other terminals and relocate it to the HEAT terminal (See
Table 9 for lead color identification). Reconnect original
lead to SPARE terminal.
f. Repeat steps a through e.
g. When correct input rate and temperature rise is achieved,
turn gas valve ON/OFF switch to OFF.
h. Remove manometer or similar device from gas valve.
i. Reinstall manifold pressure tap plug in gas valve.
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FIRE HAZARD
Leaking gas could be ignited and cause fire, explosion,
personal injury, property damage or death.
Reinstall manifold pressure tap plug in gas valve to prevent
gas leak.
j. Reinstall blower access door if removed.
k. Turn gas valve ON/OFF switch to ON.
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FURNACE OVERHEATING HAZARD
Failure to properly set temperature rise may cause excessive
furnace temperatures and shorten furnace life.
Recheck temperature rise. It must be within limits specified
on the rating plate. Recommended operation is at the mid-
point of rise range or slightly above.
6. Set thermostat heat anticipator.
a. Mechanical thermostat—Set thermostat heat anticipator to
match the amp draw of the electrical components in the
R-W circuit. Accurate amp draw readings can be obtained
at the wires normally connected to thermostat subbase
terminals, R and W. The thermostat anticipator should
NOT be in the circuit while measuring current.
(1.) Remove thermostat from subbase or from wall.
(2.) Connect an amp meter as shown in Fig. 48 across the
R and W terminals or R and W wires at wall.
(3.) Record amp draw across terminals when furnace is in
heating and after blower starts.
(4.) Set heat anticapator on thermostat per thermostat
instructions and install on subbase or wall.
b. Electronic thermostat: Set cycle rate for 4 cycles per hr.
7. Adjust blower off delay
The blower off delay has 4 adjustable settings from 90 sec to
180 sec. The blower off delay jumpers are located on the
SPEED AS SHIPPED
Common BLW
High COOL
Med-High SPARE
Med-Low SPARE
Low HEAT
10 TURNS
EXAMPLE: 5.0 AMPS ON AMMETER
10 TURNS AROUND JAWS
Fig. 48—Amp Draw Check With Ammeter
furnace control board. (See Fig. 24.)
To change the blower off delay setting, move the jumper from
one set of pins on the control to the pins used for the selected
blower off delay. Factory off delay setting is 120 sec.
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8. Set airflow CFM for cooling
Select the desired blower motor speed lead for cooling
airflow. See Table 5-Air Delivery-CFM (With Filter). See
Table 9 for lead color identification.
Step 4—Check Safety Controls
The flame sensor, gas valve, and pressure switch were all checked
in the Start-up procedure section as part of normal operation.
1. Check Main Limit Switch(es)
This control shuts off combustion control system and ener-
gizes air-circulating blower motor, if furnace overheats. By
using this method to check limit control, it can be established
that limit is functioning properly and will operate if there is a
restricted duct system or motor failure. If limit control does
not function during this test, cause must be determined and
corrected.
a. Run furnace for at least 5 minutes.
b. Gradually block off return air with a piece of cardboard or
sheet metal until the limit trips.
c. Unblock return air to cause normal circulation.
d. Burners will re-light when furnace cools down.
2. Check draft safeguard switch.
The purpose of this control is to cause the safe shutdown of the
furnace during certain blocked vent conditions.
a. Verify vent pipe is cool to the touch.
b. Disconnect power to furnace and remove vent connector
from furnace vent elbow.
c. Restore power to furnace and set room thermostat above
room temperature.
d. After normal start-up, allow furnace to operate for 2
minutes, then block vent elbow in furnace 80 percent of
vent area with a piece of flat sheet metal.
34
THERMOSTAT SUBBASE
TERMINALS WITH
THERMOSTAT REMOVED
(ANITICIPATOR, CLOCK, ETC.,
MUST BE OUT OF CIRCUIT.)
HOOK-AROUND
AMMETER
R Y W G
FROM UNIT 24-V
CONTROL TERMINALS
= 0.5 AMPS FOR THERMOSTAT
ANTICIPATOR SETTING
A96316