COOK HMD EN - Manual (Page 15)

15
Attempts to light, with visible spark, but no flame Troubleshooting
No
No
No
No
Check the supply gas pressure and compare it with the unit’s nameplate
pressure requirements. Adjust the supply regulator as needed until
the supply gas pressure is within the specified range (see below). The
nameplate is located on the outside of the unit on the control panel side.
With all access panels in place, the fan running and discharging 70ºF
(21ºC) air, connect a U-Tube manometer to the outer sensing probes
(see below) and measure the static pressure across the burner. The
proper static pressure should be (check CFM / Static Pressure chart
on page 8). If needed, evenly adjust the baffles, keeping the burner
centered in the opening until the required pressure is obtained. The
pressure drop was set at the factory and may not need adjustment.
When required pressure is obtained, be sure to reconnect the outer
sensing probes. This process may need to be repeated until the proper
pressure is achieved. This adjustment will change the air quantity
delivered by the unit and therefore the air quantity delivered should be
rechecked. Refer to the Blower Start-Up section.
To increase the static pressure decrease the opening.
To decrease the static pressure increase the opening.
Purge the air.
Is the inlet gas pressure
between the min and
max?
Is there air in the gas
line?
Is the pressure drop
across the burner
correct? (check chart
on page 8)
Is there still not a proper
spark?
Yes
Yes
Yes
Yes
The wires may be switched. Uncross the spark wires.
Make sure the spark gap is .062 in.
Replace spark the plug.
Consult factory
Refer to the control panel parts list when troubleshooting.