InsTAllATIon - operATIon
operATIon
prior to operation
IMPORTANT
1. To prevent premature heat exchanger failure, observe
heat exchanger tubes. If the bottom of the tubes become
red while blower and furnace are in operation, check
to be sure the blower has been set to the proper rpm
for the application. Refer to pages 9 and 10 for Blower
Adjustments.
2. Start-up and adjustment procedures should be performed
by a qualified service agency.
Although this unit has been assembled and fire-tested at the
factory, the following pre-operational procedures should be
performed to assure proper on-site operation.
1. Turn off power to the unit at the disconnect switch. Check that
fuses or circuit breakers are in place and sized correctly. Turn
all hand gas valves to the "OFF" position.
2. Remove the side control access panel.
3. Check that the supply voltage matches the unit supply voltage
listed on the Model Identification plate. Verify that all wiring is
secure and properly protected. Trace circuits to insure that the
unit has been wired according to the wiring diagram.
4. Check to insure that the venting system is installed correctly
and free from obstructions. Before you start use the following
steps to verify that the venting system is adequately sized:
a. Seal any unused openings in the venting system.
b. Inspect the venting system for proper size and horizontal
pitch, as required in the National Fuel Gas Code ANSI
Z223.1 or CSA B149.1 Installation Code-latest edition
and these instructions. Determine that there is no
blockage or restriction, leakage, corrosion and other
deficiencies, which could cause an unsafe condition.
c. In so far as practical, close all building doors and
windows and all doors between the space in which
the appliance(s) connected to the venting system are
located and other spaces of the building. Turn on clothes
dryers and any exhaust fans such as range hoods and
bathroom exhausts, so they shall operate at maximum
speed. Do not operate a summer exhaust fan. Close
fireplace dampers.
d. Follow the lighting instructions. Place the appliance
being inspected in operation. Adjust thermostat so that
the appliance will operate continuously.
e. After it has been determined that each appliance
connected to the venting system properly vents when
tested as outlined above, return doors, windows, exhaust
fans, fireplace dampers and any other gas-burning
appliance to their previous conditions of use.
f.
If improper venting is observed during any of the above
tests, the venting system must be corrected.
5. Check to see that there are no obstructions to the intake and
discharge of the unit.
6. Check fan clearance. Fan should not contact casing when
spun by hand.
7. Check to make sure that all filters are in place and that
they are installed properly according to direction of air flow
(if applicable).
8. Perform a visual inspection of the unit to make sure no
damage has occurred during installation.
9. Check that all horizontal deflector blades are open a minimum
of 30° as measured from vertical.
10. Turn on power to the unit at the disconnect switch.
11. Check the thermostat, ignition control, gas valve, and supply
fan blower motor for electrical operation. If these do not
function, recheck the wiring diagram.
12. Check the blower wheel for proper direction of rotation when
compared to the air flow direction arrow on the blower housing
(if applicable). Blower wheel rotation, not air movement, must
be checked as some air will be delivered through the unit with
the blower wheel running backwards.
13. For blower units, check the blower speed (rpm). Refer to
Blower Adjustments for modification.
14. Check the motor speed (rpm).
15. Check the motor voltage.
16. Check the motor amp draw to make sure it does not exceed
the motor nameplate rating.
17. Recheck the gas supply pressure at the field installed manual
shut-off valve. The minimum inlet pressure should be 6" W.C.
on natural gas and 11" W.C. on propane gas. The maximum
inlet pressure for either gas is 14" W.C. If inlet pressure
exceeds 14" W.C., a gas pressure regulator must be added
upstream of the combination gas valve.
18. Open the field installed manual gas shut-off valve.
19. Place the manual main gas valve on the combination gas
valve in the "On" position. Call for heat with the thermostat.
20. Check to make sure that the main gas valve opens. Check the
manifold gas pressure (See Main Gas Adjustment) while the
supply fan blower is operating.
21. Check to insure that gas controls sequence properly (See
Control Operating Sequence). If you are not familiar with
the unit's controls (i.e. combination gas control), refer to the
control manufacturer's literature supplied with the unit.
22. Once proper operation of the unit has been verified,
remove any jumper wires that were required for testing.
24. Replace the side control access panel.
main Burner Adjustment
The gas pressure regulator (integral to the combination gas
control) is adjusted at the factory for average gas conditions. It is
important that gas be supplied to the unit heater in accordance
with the input rating on the serial plate. Actual input should be
checked and necessary adjustments made after the unit heater is
installed. Over-firing, a result of too high an input, reduces the life
of the appliance and increases maintenance. Under no circum-
stances should the input exceed that shown on the serial plate.
Measuring the manifold pressure is done at the outlet pressure
tap of the gas valve.
To Adjust the manifold pressure
1.
Move the field installed manual shut-off valve to the "OFF"
position.
2.
Remove the 1/8" pipe plug from the outlet pressure tap on
the gas valve and attach a water manometer of "U" tube type
which is at least 12" high.
3.
Move the field installed manual gas shut-off valve to the
"ON" position.
4.
Create a high-fire call for heat from the thermostat.
5.
Refer to Table 15.1 to determine the correct high fire
manifold pressure for the gas type of the unit. Adjust the
main gas pressure regulator spring to achieve the proper
manifold pressure (for location, see the combination gas
control literature supplied with unit).
6.
After adjustment, move the field installed manual shut-off
valve to the "OFF" position and replace the 1/8" pipe plug.
7.
After the plug is in place, move the field installed manual
shut-off valve to the "ON" position and recheck pipe plugs for
gas leaks with soap solution.
6-583.2
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