
9
24
1
2
4
Fig. 5
Multifunctional Control
1. Operating control
2. Burner Pressure Adjuster
3. Outlet Pressure test point
4. Pilot Adjuster
Fig. 7a
Modairflow Functional Diagram
3
6.4.2
Apply the pressure set arrow to indicate the appropriate burner pressure on the data badge.
6.5
EXTINGUISHING OF PILOT AND MAIN BURNERS:
6.5.1
On the Multifunctional Control, rotate the OPERATING CONTROL clockwise to the ‘
O
’ position and ensure that the
OPERATING CONTROL fully resets, and both Pilot and Main Burners are extinguished.
6.5.2
On the Multifunctional Control, remove the pressure test gauge and refit the Outlet Pressure test point cover, and test
for gas soundness.
6.6
TEMPERATURE RISE CHECK:
6.6.1
Ignite the Pilot and Main Burners and allow to operate for 15 minutes to ensure stability.
6.6.2
With the Main Burner operating continually, check that the temperature rise across heater is between 45
o
C - 55
o
C,
setting the fan speed accordingly, (decrease fan speed to increase temperature rise). For MODAIRFLOW heaters,
adjusting the balancing screw sets fan speed; for non-MODAIRFLOW heaters, fan speed is adjusted by selecting the
fan speed at the control panel (decrease voltage selection to decrease fan speed).
6.3.6
Ensure that the pilot flame envelops the thermocouple tip, adjusting the Pilot Adjuster as required (Refer Figs. 4 and
5).
6.3.7
Set the Heater Electricity supply
ON
.
6.3.8
Set the Time Control to the required Heating On periods.
6.3.9
Set the Selector switch to ‘TIMED’.
6.3.10 Set the Thermista-stat or room thermostat to MAXIMUM.
6.3.11 Ensure that the Main Burner has now ignited.
6.3.12 Test for gas leakage at the supply, Multifunctional Control, and Pilot and Main Burners using proprietary detection
fluid, sealing any leaks found.
6.3.13 Allow the heater to operate for a minimum of 15 minutes to ensure stability.
6.4
MAIN BURNER PRESSURE TEST:
NOTE: AIR HEATER BURNERS ARE FACTORY SET TO PROVIDE A NOMINAL HIGH RATE OUTPUT AS DETAILED IN SUB
PARA 1.2
6.4.1
Referring to Table 4 and Fig. 5 below, ensure that the pressure test gauge indicates correct burner pressure, resetting
if required as follows:
a.
At the Multifunctional Control:
i.
Remove the Burner Pressure Adjuster cover.
ii.
Set the Burner Pressure Adjuster to provide a pressure test gauge indication for the correct burner
pressure as detailed in Table 4.
iii.
Refit the Burner Pressure Adjuster cover.