Sequence Of Operation - Napoleon WPV-N Série Instructions D'installation Et D'opération

74
ALWAYS DISCONNECT THE ELECTRICAL SUPPLY TO THE FURNACE BEFORE REMOVING
UM
THE FURNACE GAS TRAIN IS DESIGNED TO OPERATE AS A SEALED UNIT. BE SURE
THAT THE BURNER COMPARTMENT ACCESS DOOR IS PROPERLY IN PLACE BEFORE
The furnace achieves its high effi ciency in three general areas. First, there is no wasteful standing pilot. The
furnace consumes no gas in between cycles. Secondly, the furnace is designed to allow very small amounts of
excess air in the combustion process. Older furnaces had heat exchangers which were commonly 40% larger
than necessary for complete combustion. While this prevented the creation of carbon monoxide, the heated
excess air was expelled up the chimney where it could not benefi t the interior of the home. Special safety
controls now prevent the formation of carbon monoxide.
The third general area is the recovery of the latent heat contained in the fl ue gas, which is comprised of water
vapor and carbon dioxide. By condensing the fl ue gas in the furnace recovery coil, heat that would otherwise be
wasted to the outdoors, is captured and redirected into the duct system where it contributes to home comfort.
Each pound of condensation formed releases approximately 970 Btu's. Your furnace may condense up to 1/2
gallon (1.89L) (5 pounds) (2.27kg) of water per hour if running continuously.
This condensation must be properly disposed into a sump or drainage system. The condensate lines must
remain clear and free fl owing. Do not allow plastic drain lines to become pinched or kinked. A blocked drain
line can cause the furnace to operate erratically, or not at all.
IMPORTANT:
Your furnace should be cleaned and inspected annually by a trained and qualifi ed
service technician. Your service technician has the knowledge and test equipment to
determine the condition of your furnace.
4.7

SEQUENCE OF OPERATION

1. Room temperature drops causing the room thermostat call for fi rst stage heat by connecting "W1" to "R".
The control verifi es the limit switch is closed and both low and high pressure switches are open. The
control energizes the exhauster motor on high speed and waits for the low pressure switch to close. The
exhauster remains on high speed and begins a 15 second pre-purge period. The high pressure switch is
ignored. If the low pressure switch does not close within 60 seconds, the control will fl ash "2" on the Red
Status LED, and de-energize the exhauster for 60 minutes.
2. When the 15 second pre-purge time has elapsed, the control energizes the HSI output for a 15 second
warm-up period (15 seconds on retries). The control energizes the low main gas valve. 4 seconds after the
gas is energized, the control de-energizes the HSI output and leaves the gas energized another 1 second
for fl ame proving. If fl ame is present at the end of trial for ignition time, the control leaves the gas valve
energized, exhauster on high speed, and begins heat blower on delay. The control always ignites on high
exhauster/low gas and ignores second stage call for heat until low fi re is established for 15 seconds.
3. Blower on delay time begins when the gas valve is energized. The control provides the motor low heat
speed signal when fl ame is proven, and starts a 30 second blower delay before full capacity blower level.
4. When there is a demand for 2nd stage heat from thermostat W2 or automatic staging, the control changes
the exhauster from low to high speed. When high pressure switch closes, the control changes indoor
blower speed from Low heat to High heat and energizes high gas output. If the high pressure switch is
open the Green LED will fl ash. If the high pressure switch is closed the Green LED will be on. High gas
valve drops out while High pressure switch is open because it is directly in series with the high pressure
switch.
W415-2308 / B / 11.04.19
WARNING
!
THE BURNER COMPARTMENT ACCESS DOOR.
CAUTION
!
ATTEMPTING TO RESTART THE FURNACE.
!
H3.30
!
H27.6.2