PVI Industries FIREPOWER PV500-9 - Manual (Page 3)

PV500-9 04-2000 (3) Section 9
POWER GAS BURNER START-UP (Con’t)
clearance). Ensure plate is seated firmly against the
gas spider and tighten the plate retaining screws.
Recheck electrode setting as to gap and position.
15. Replace nozzle assembly; be sure to connect the flame
and spark rod wires before installing nozzle assembly
fully into blast tube. Check to be sure connectors on
the ends of the flame and spark rod wires have a good
contact. Look for properly stripped wire ends. Be sure
connectors are firmly attached to the flame and ignition
rod ends. Insulating boots can give a false feeling of
proper seating. BE CAREFUL NOT TO MOVE
ELECTRODES. Be careful not to bump electrodes
Check fan wheel for free rotation.
16. Reinstall orifices in unions (if required). Reinstall burner
cover.
17. Connect a test meter to the control for reading the
flame response signal.
NOTE: Some controls read the flame signal in micro
amps and some in volts DC. The TFM series control has
two terminals marked for reading volts DC. The S89
control uses a micro amp signal for measuring flame
strength. For this control, a meter must be hooked in
series with the flame rod wire. Disconnect the leadwire
at the S89 sensor terminal. Connect the positive lead of
the meter to the quick-connect sensor terminal on the
S89 and the negative lead to the free end of the sensor
leadwire.
18. Be sure the tank is filled with water. Once the burner is
reassembled, two devices to read pressure, preferable
U-tube manometers, will be needed to read gas
pressures. Connect one to read the inlet pressure of
the burner. This is the pressure measured before all
components in the gas train. The manometer must stay
connected throughout the testing, as the inlet pressure
must be monitored during the firing of the burner.
Record static pressure. It must not exceed 14” W.C. for
burners with inputs through 3,200,000 Btu/h. For inputs
above 3,200,000 Btu/h, refer to the appliance date
plate for the correct maximum inlet pressure Pressures
above this could cause damage to the diaphragm in the
gas valve or pressure regulator.
19. Burners with pilot:
A. Connect the manometer to the manifold test port at
the shutoff valve closest to the burner. Turn the main
gas shutoff valve off. Set the air shutter as shown on
the tag attached to the gas train, (see Figure 9-4 and
9-5). This may not be the exact setting you end with,
but it is a good starting point. Turn the unit on using
the rocker switch on the side of the control enclosure
assembly and the toggle switch on the burner. If the
operating control switches are closed, the burner
should come on and pre-purge begin.
B. If nothing happens, check the control to be sure it is
not in the tripped position and reset it by pushing
flame safeguard reset button. The burner should pre-
purge for not longer than thirty seconds. The TFM
series control will have either an MT30-4, MT30-10
or MT12-5 time card. The “30 indicated a 30-second
purge time and the “4”, “5” or “10” indicated a 4-
second, 5-second, or 10-second trial for ignition
period, commonly called TFI.
When the blower motor starts, the air switch which
proves air flow should close and terminal 6 will be
powered. This starts the pre-purge timing sequence.
After purging is complete, terminal 3 or 4 on the
TFM control are energized. Terminal 3 energizes
the pilot valve and terminal 4 energizes the ignition
transformer. At this time, the pilot is established.
The VDC reading on thermometer should read a
steady 14-17 VDC for a TFM control. Each different
control will have the required flame response signal
stamped on it. This is the minimum for it to properly
operate. If the pilot fails to light during the initial
ignition period, it is probably due to air in the line.
The control will lock out. Wait one minute and push
the flame safeguard reset button to restart burner
and begin the purge cycle again.
Now, set the pilot pressure (measured downstream
of gas valve) at the pressure shown on the tag
attached to the gas train. Next, open the main gas
valve slowly. Set manifold pressure at the pressure
shown on the tag attached to the gas train. Do not
screw the adjusting nut of the regulator in past the
point where no further increase in manifold pressure
is noted. Check the incoming pressure with the
burner running. This is recorded as inlet flow
pressure.
Our standard flow pressure requirements are:
a. 5” W.C. with 8” W.C. flow on burners with inputs
through 1,600,000 Btu/h.
b. 8” W.C. with 11” W.C. flow on burners with inputs
from 2,000,000 Btu/h through 3,200,000 But/h.
c. For inputs above 3,200,000 Btu/h, refer to the tag
attached to the gas train for the correct inlet
pressures.
C. If the required manifold cannot be reached, check
the inlet pressure. It should be a minimum of that
shown above with the burner running on full input. It
is important that the incoming pressure does not fall
below these minimums or nuisance control lockouts
could occur.
NOTE: Where low gas pressure is a problem, special
arrangements may have been made to fire the burner
with reduced pressure. The appliance data decal will
reflect this information.