Carrier WEATHERMAKER 8000 58WAV - Manual (Page 9)

remains on until the end of the purge period, then shuts off
until the end of the ignition warm up and trial for ignition
periods (a total of 24 sec). The blower then comes back on at
heating speed.
When the W input signal disappears, the control begins the
normal inducer post-purge period and the blower changes to
cooling speed after a 1-sec delay. If the W-Y-G signals should
disappear at the same time, the blower remains on for the
selected heating blower off delay period, and the inducer goes
through its normal post-purge period. If the W-Y inputs
should disappear, leaving the G signal input, the control goes
into continuous blower mode and the inducer remains on for
the normal post-purge period.
While in heat pump mode, the control uses only the 17-sec
ignition warm-up period and does not use the 45-sec period at
all. Any time the control senses false flame, the control locks
out of heating mode. This occurs because the control cannot
sense the W input due to the false flame signal, and as a result,
sees only the Y input and goes into cooling mode blower off
delay. All other control functions remain in standard format.
EAC terminals are energized during blower operation.
HUM-1 is energized only during gas heat or defrost operation.
START-UP PROCEDURES
1. Self-test—The furnace features a self-test system to help
diagnose a system problem in the case of a component failure.
Two test pins (ST-1 and ST-2) are located in the lower
right-hand corner of the control board as shown in Fig. 9. To
initiate the self-test procedure, momentarily short across the 2
pins for approximately 0.5 sec.
A91060
Fig. 9—Control Center
NOTE:
The self-test feature does not operate if the control board
is receiving any thermostat signals.
The self-test sequence is as follows:
a. The furnace control checks itself, then operates the inducer
motor for 10 sec, then stops.
b. The hot surface ignitor is then energized for 15 sec, then
de-energized.
c. The humidifier relay is then energized for 10 sec, then
de-energized.
d. The blower motor operates on cooling speed for 10 sec,
then stops.
e. The blower motor operates on heating speed for 10 sec,
then stops.
2. Purge gas lines—After all connections have been made, purge
the lines and check for leaks.
A WARNING
Never purge a line into a combustion chamber. Never use
matches, candles, flame or other sources of ignition for the
purpose of checking leakage. Use a soap-and-water solution
to check for leakage. A failure to follow this warning can
cause a fire, explosion, personal injury, or death.
3. To operate furnace, follow procedures on operating instruc­
tions label attached to furnace.
4. With furnace operating, set thermostat below room tempera­
ture and observe that furnace goes off. Set thermostat above
room temperature and observe that furnace restarts.
ADJUSTMENTS
1. Set gas input rate.
There are 2 methods of adjusting the gas input rate. The
preferred method is by using Table 6 and following instruc­
tions in item a. The second method is by clocking the gas
meter and following instructions in item b.
The gas valve regulator has been nominally set at 3.5-in. wc
for natural gas. When adjusting input rate, do not set manifold
pressure above 3.8- in. wc or below 3.2-in. wc.
a. Check gas input rate using Table 6.
(1.) Obtain average yearly heat value for local gas supply.
(2.) Obtain average yearly specific gravity for local gas
supply.
(3.) Verify furnace model. Table 6 can only be used for
model 58WAV Furnaces.
(4.) Check and verify orifice size in furnace. NEVER
ASSUME THE ORIFICE SIZE. ALWAYS CHECK
AND VERIFY.
(5.) Find natural gas heat value and specific gravity in
Table 6.
(6.) Follow heat value and specific gravity lines to point of
intersection. Find orifice size and manifold pressure
settings for proper operation at given natural gas
conditions.
EXAMPLE:
Heat value = 1070 Btu/cu ft
Specific gravity = 0.58
Therefore Orifice No. 44 *
Manifold pressure 3.3-in. wc
* The furnace is shipped with No. 43 orifices. Therefore, in
this example, all main burner orifices must be changed and
manifold pressure must be adjusted.
(7.) Proceed to item c. to adjust manifold pressure,
b. Check gas input rate by clocking gas meter.
(1.) Obtain average yearly heat value for local gas supply.
(2.) Check and verify orifice size in furnace. NEVER
ASSUME THE ORIFICE SIZE. ALWAYS CHECK
AND VERIFY.