National Comfort Products Comfort Pack U Series, Руководство по установке

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17
Installation Guide | Comfort Pack with 80% Gas Heat
Abnormal Functions
• Interrupted Thermostat Call for Heat
– If the thermostat
demand for heat is removed before the flame is recognized, the
control will run the venter motor for the post purge period and
de-energize all outputs. If the thermostat demand for heat is
removed after successful ignition, the control will de-energize
the gas valve, run the venter motor through post purge, and run
the blower motor on heat speed for the selected delay off time.
• Soft Lockout
– The control shall not initiate a call for heat or call
for continuous fan while in lockout. The control will still respond
to an open limit and undesired flame. Lockout shall automatically
reset after one hour. Lockout may be manually reset by removing
power from the control for more than one second or removing
the thermostat call for heat for more than one and less than 20
seconds.
• Hard Lockout
– If the control detects a fault on the control
board, the status LED will be de-energized, and the control
will lockout as long as the fault remains. A hard lockout will
automatically reset if the hardware fault clears.
• Power Interruption
– During a momentary power interruption
or at voltage levels below the minimum operating voltage for
line voltage the system will self-recover without lockout when
voltage returns to the operating range. During a momentary
power interruption of low voltage the board will enter a soft
lockout. Power interruptions of less than 80mS shall not cause
the control to change operating states. Power interruptions
greater than 80mS may cause the control to interrupt the current
operating cycle and re-start.
• Ignition Retry
– If flame is not established on the first trial for
ignition, the control de-energizes the gas valve and the venter
motor remains energized for an inter-purge period of 30 seconds.
The spark and gas valve are then re-energized, and the control
initiates another trial for ignition. If flame is not established on the
second trial for ignition, the control de-energizes the gas valve,
energizes the blower motor on heat speed, and venter motor
remains energized. The blower motor is shut off after a short
period. When the blower motor de-energizes, the spark and gas
valve are re-energized and the control initiates another trial for
ignition. (This blower delay is a self-healing feature for an open
auxiliary limit switch). If flame is not established on the third
trial for ignition, the control de-energizes the gas valve, and the
venter motor remains energized for an inter-purge period of 30
seconds. The control then re-energizes the gas valve and spark
and initiates another trial for ignition. If flame is not established
on the fourth trial for ignition (initial try plus 3 re-tries), the
control de-energizes the gas valve and goes into lockout. The
control goes to one flash on the green LED to indicate ignition
failure lockout.
Installation Codes
These units must be installed in accordance with local building
codes. In the absence of local codes, in the United States, the just
be installed in accordance with the National Fuel Gas Code (latest
edition). A Canadian installation must be in accordance with the
CAN/CGA-B149.1 and B149.2 Installation Code for Gas Burning
Appliances and Equipment. These codes are available from CSA
Information Services, 1-800-463-6727. Local authorities having
jurisdiction should be considered before installation is made to
verify local codes and installation procedure requirements.
High Altitude Operation
If the heater is being installed at an elevation above 2000 ft.
(610m), the input rate will have to be derated. This is done by
adjusting the valve outlet pressure (See page 18). In addition, if
the heater is being installed at an altitude above 6000 ft. (1830m),
the pressure switch will have to be changed. Adjusting the valve
outlet pressure is done after the heater is in operation; follow
the instructions below. If the pressure switch needs changed, do
that before the heater is operated (see Figure 1).
Figure 1
Heat Section Burner/Control Compartment
(Note: Unit side panel is removed for clarity; side panel is not
removable. Access to the burner/control compartment is through
the small rear access panel.)