Maintenance; If Main Burner Will Not Come On With Call For Heat - Honeywell VR8305 User Manual

WARNING
!
FIRE OR EXPLOSION HAZARD
CAN CAUSE PROPERTY DAMAGE,
SEVERE INJURY, OR DEATH
Improper cleaning or reassembly may cause gas
leakage. When cleaning, ensure that control is
reassembled properly and perform gas leak test.
Regular preventive maintenance is important in appli-
cations that place a heavy load on system controls, such as
in the commercial cooking and agricultural and industrial
industries because:
• The equipment operates 100,000-200,000 cycles per
year in many such applications, particularly com-
mercial cooking. Such heavy cycling can wear out
the gas control in one to two years.
• Exposure to water, dirt, chemicals and heat can
damage the gas control and shut down the control
system.
The maintenance program should include regular check-
out of the gas control, see Start-Up and Checkout, page 6,
and the control system as described in the appliance
manufacturer's literature.
Maintenance frequency must be determined individu-
ally for each application. Some considerations are:
• Cycling frequency. Appliances that may cycle
100,000 times annually should be checked monthly.
• Intermittent use. Appliances that are used seasonally
should be checked before shutdown and again before
the next use.
• Consequence of unexpected shutdown. Where the
cost of an unexpected shutdown would be high, the
system should be checked more often.
• Dusty, wet, or corrosive environment. Since these
environments can cause the gas control to deteriorate
more rapidly, the system should be checked more
often.
The gas control should be replaced if:
• It does not perform properly on checkout or trouble-
shooting.
• The gas control knob is hard to turn or push down, or
it fails to pop back up when released.
• The gas control is likely to have operated for more
than 200,000 cycles.

Maintenance

! WARNING
FIRE OR EXPLOSION HAZARD
CAN CAUSE PROPERTY DAMAGE,
SEVERE, INJURY, OR DEATH
Do not disassemble the gas control; it contains no
replaceable components. Attempted disassembly
or repair may damage the gas control.
CAUTION
!
Do not apply a jumper across or short the valve
coil terminals. Doing so may burn out the heat
anticipator in the thermostat or damage the DI
module.
IMPORTANT: Allow 60 seconds after shutdown before
re-energizing step-opening model to ensure lightoff at
step pressure.
IF MAIN BURNER WILL NOT COME ON WITH
CALL FOR HEAT
1. Ensure gas control knob is in the ON position.
2. Adjust thermostat several degrees above room tem-
perature.
3. Using ac voltmeter, measure voltage across MV
terminals at gas control.
4. If no voltage is present, check control circuit for
proper operation.
5. If proper control system voltage is present, replace
gas control.
8
Service