Carrier 58PAV - Manual (Page 12)

tion B. The water heater vent connector must be sized
per the National Fuel Gas Code.
E. Removal of Existing Furnaces From Common Vent
Systems
1. These steps shall be followed with each appliance
remaining connected to the common vent system
placed in operation, while the other appliances remain­
ing connected to the common vent system are not in
operation.
2. Seal any unused openings in the common vent system.
3. Visually inspect the vent system for proper size and
horizontal pitch, and determine there is no blockage or
restriction, leakage, corrosion, and other deficiencies
which could cause an unsafe condition.
4. Insofar as practical, close all building doors and win­
dows and all doors between the space in which the
appliances remaining connected to the common vent
system are located and other spaces of the building.
Turn on clothes dryers and emy appliance not con­
nected to the common vent system. Turn on any
exhaust fans, such as range hoods and bathroom
exhausts, so they operate at maximum speed. Do
not operate a summer exhaust fan. Close fireplace
dampers.
5. Follow the lighting instructions and place the apph-
ance in operation. Adjust the thermostat so appliance
will operate continuously.
6. Test for flue gas spUlage at the drafthood rehef open­
ing (or draft safeguard tube opening) after 5 minutes of
main burner operation. Use the fleime of a match or
candle, or smoke from a cigarette, etc.
7. After it has been determined that each appliance
remaining connected to the common vent system
properly vents when tested as above, return doors, win­
dows, exhaust fans, fireplace dampers, any other gas-
buming appliances to their previous condition of use.
8. If improper venting is observed during any of the
above tests, the common vent system must be cor­
rected. The vent system or vent connectors may need
to be resized. Resize any 58PAV Furnaces vent system
according to these instructions. For any other appli­
ances when resizing vent systems or vent connectors,
the system or connector must be sized to approach the
rninimum size as determined using the appropriate
table found in Appendix G of the National Fuel Gas
Code, ANSI Z223.1 or Section 5 of CAN/CGA.B149 for
Canadian installations.
VIII. STARTUP, ADJUSTMENT, AND SAFETY CHECK
A. General
The furnace must have a 115-VAC power supply properly
connected and grounded. Proper polarity must be main­
tained for proper operation. Thermostat wire connections at
R, W, C, and Y must be made at the 24-volt terminal block
on the control board. The gas service pressure must not
exceed 0.5 psig (14 in. wc), but must be no less than 0.16
psig (4.5 in. wc).
Before operating the furnace, check each manual reset
switch for continuity. If necessary, press the button to reset
the switch.
The blower compartment door must be in place to complete
the 115-VAC circuit to the furnace.
A CAUTION
This furnace is equipped with a manual reset limit
switch in the gas control area. The switch will open and
shutoff power to the gas valve if a flame rollout or over­
heating condition occurs in the gas control area. Do not
bypass the switch. Correct inadequate combustion air
supply problem and reset the switch.
B. Sequence of Operation
Using the schematic diagram. Fig. 10, follow the sequence
of operation through the different modes. This furnace has a
new and unique control system, therefore, read and follow
the wiring diagram very carefully.
1. Heating mode
The waU thermostat “calls for heat,” closing the R and
W circuit. The furnace control performs a selfcheck,
verifies the pressure switch contacts are open, and
starts the inducer motor.
a. Prepurge period—As the inducer motor comes up to
speed, the pressure switch contacts close to begin a
15 second prepurge period.
b. Ignitor warm up—At the end of the prepurge
period, the ignitor is energized for a 17 second igni­
tor warm-up period. If ignition is not established
during the first cycle, the next warm-up period is
increased to 45 seconds. AH subsequent ignition
cycles wiU be 45 seconds, or until the 115-VAC
power supply is interrupted. By interrupting the
115-VAC power supply, the warm-up period is auto­
matically reset to 17 seconds.
c. Ignition sequence—When the ignitor warm-up
period is completed the gas valve opens, permitting
gas flow to the burners where it is ignited. After 5
seconds, the ignitor is deenergized and a 2 second
flame sensing period begins.
d. Flame sensing—When burner flame is sensed, the
control begins the blower “on” delay period and
continues holding the gas valve open. If burner
flame is not sensed, the control will close the gas
valve, and control wUl repeat ignition cycle.
e. Blower on delay—60 seconds after burner flame is
proven, the blower motor is energized on heating
speed. Simultaneously, the humidifier and electronic
air cleaner terminals (HUM-1 and C for humidifier,
EAC-1 and EAC-2 for electronic air cleaner) are
energized.
f. Blower off delay—When the thermostat is satisfied,
the circuit between R and W is broken, deenergizing
the gas valve stopping gas flow to the burners. The
blower motor, humidifier, and air cleaner wUl remain
energized 90, 135, 180, or 225 seconds (depending
on the blower off-time selection). The furnace is
factory-set for a 135-second blower off delay.
g. Post purge—The inducer motor will remain ener­
gized 5 seconds after the burners are extinguished.
2. Cooling mode
The thermostat “calls for cooling” closing R-G and R-Y
circuits. The R-Y circuit starts the outdoor condensing
unit, and the combined R-Y and R-G circuit starts the
furnace blower motor on cooling speed. The electronic
air cleaner EAC terminals are energized with 115-VAC
when the blower is operating on cooling speed.
When the thermostat is satisfied, R-G and R-Y circuits
are broken. The furnace blower wUl continue operating
on cooling speed for an additional 90 seconds.
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