292278-UIM-A-0108
22
Unitary Products Group
TOOLS AND INFORMATION THAT WILL BE
REQUIRED IN ORDER TO PROPERLY PERFORM THE
FURNACE STARTUP PROCEDURE.
1.
Call the local gas supplier to obtain heating value of the natural
gas. If you cannot obtain the heating valve of the gas from the gas
supplier, you may use a default value of 1030 BTU/SCF (38.8 MJ /
m³).
2.
You will need a thermometer or portable digital thermometer to
read the supply and return air temperatures.
3.
You will need a U-tube manometer or digital equipment that has
the ability to read pressures between 0 – 15” in.w.c (0 - 3.73 kPa)
in order to measure the gas line and the manifold pressures.
4.
You will need a 3/16” Allen wrench for the pressure port plugs in
the gas valve.
5.
You will need 2 pieces of 1/8” (0.3 cm) ID flexible tubing that is 12”
(30 cm) in length, 2 – pieces of 1/8” (0.3 cm) tubing that are 4”
(10.0 cm) in length, a 1/8” (0.3 cm) tee and a 1/8” (0.3 cm) adapter
to connect the U-tube manometer or the digital pressure measur-
ing equipment to the gas valve pressure ports.
There is an accessory kit (1PK0601) available from Source 1, which
has the following items:
•
1 - 12” (30 cm) length x 1/8” (0.3 cm) diameter tubing
•
2 – pieces of 4” (10 cm) length x 1/8” (0.3 cm) diameter tubing
•
1 - 5/16” (0.8 cm) tee
•
1 – 5/16” (0.8 cm) x 1/8” (3.175 mm) reducing coupling
•
1 – 1/8” (0.3 cm) adapter
There is a accessory kit (1PK0602) available from Source 1, which has
the following items:
•
12” (30 cm) length x 1/8” (0.3 cm) diameter tubing
•
2 – pieces of 4” (10 cm) length x 1/8” (0.3 cm) diameter tubing
•
1 - 5/16” (0.8 cm) tee
•
1 – 5/16” (0.8 cm) x 1/8” (0.3 cm) reducing coupling
•
1 – 1/8” (0.3 cm) adapter
•
1 - Dwyer – Manometer
These items are required in order to properly perform the required star-
tup procedure.
GAS PIPING LEAK CHECK
IMPORTANT:
Burner ignition may not be satisfactory on first startup
due to residual air in the gas line or until gas manifold pressure is
adjusted. The ignition control will make three attempts to light before
locking out.
It is recommended that when the gas supply is first connected to the
furnace, the ground union be loosened until the odor of gas is detected.
When gas is detected, immediately tighten the union and check for gas
leaks. Allow five minutes for any gas to dissipate before continuing with
the startup procedure. Be sure that proper ventilation is available to
dilute and carry away any vented gas.
With furnace in operation, check all of the pipe joints, gas valve connec-
tions and manual valve connections for leakage using an approved gas
detector, a non-corrosive leak detection fluid or other leak detection
methods. Take appropriate action to stop any leak. If a leak persists,
replace the faulty component.
The furnace and its equipment shutoff valve must be disconnected from
the gas supply during any pressure testing of that system at test pres-
sures in excess of 1/2 PSI (3.45 kPa).
The furnace must be isolated from the gas supply piping system by
closing the equipment shutoff valve during any pressure testing of the
gas supply system.
SETUP TEST MODE
During normal operation, the furnace input rate can vary between 35%
and 100% of full nameplate input, making it difficult to check for proper
operation. To help with the furnace startup process, the control has a
TEST MODE available that allows the furnace input rate to stay at a
constant input rate. To access this TEST MODE perform the following
sequence:
1.
With power to the board on and with no thermostat calls (no call for
heating, cooling or continuous fan), push and hold the TEST but-
ton on the board for one second. The LED on the board will glow
red.
2.
Release the TEST button. The LED on the board will flash a rapid
green signal, indicating that TEST MODE is activated.
3.
Turn the thermostat to call for heat (R & W signal).
4.
The furnace will light and operate at high (100%) firing rate. The
furnace firing rate should be checked at this level to confirm that
the furnace is not overfired or underfired.
5.
To run the furnace at minimum rate (35%), press the ERROR but-
ton once. The LED will flash one green flash to confirm.
6.
To run the furnace at a middle rate (70%), press the ERROR but-
ton twice within a five-second period. The LED will flash green two
times to confirm.
7.
To again operate the furnace at maximum (100%) rate, press the
ERROR button three times within a five-second period. The LED
will flash green three times to confirm.
8.
If the thermostat call for heat is removed, the LED will flash a rapid
green signal, indicating that the furnace is still in TEST MODE.
9.
When startup tests are completed, turning off power to the board
will take the furnace out of TEST MODE and will restore normal
operation. The furnace will automatically return to normal opera-
tion after 150 minutes if power is not cycled.
CALCULATING THE FURNACE INPUT
(NATURAL GAS)
NOTE:
Burner orifices are sized to provide proper input rate using natu-
ral gas with a heating value of 1030 BTU/Ft
3
(38.4 MJ/m
3
). If the heat-
ing value of your gas is significantly different, it may be necessary to
replace the orifices.
NOTE:
Front door of burner box must be secured when checking gas
input.
1.
Turn off all other gas appliances connected to the gas meter.
2.
At the gas meter, measure the time (with a stop watch) it takes to
use 2 cubic ft. (0.0566 m
3
.) of gas.
3.
Calculate the furnace input by using one of the following equa-
tions.
FIRE OR EXPLOSION HAZARD
Failure to follow the safety warnings exactly could result in serious
injury, death or property damage.
Never test for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection of leaks
to check all connections. A fire or explosion may result causing
property damage, personal injury or loss of life.
