Honeywell VR8304 installation instructions Maintenance, Check Safety and Shutdown Performance

VR8304 INTERMITTENT PILOT COMBINATION GAS CONTROL

5.Carefully check main burner lightoff at the step pres- sure. Ensure the main burner lights smoothly and with- out flashback to the orifice and that all ports remain lit. Cycle the main burner several times, allowing at least

30 seconds between cycles for the regulator to resume the step function. Repeat after allowing the main burner to cool. Readjust the full rate outlet pres- sure if necessary to improve lightoff characteristics.

Table 6. Pressure regulator specification (pressures in inches WC)

				Outlet Pressure
		Nominal inlet	Nominal factory setting			Setting range
Model	Type of gas	pressure range	Step	Full rate		Step	Full rate
Standard, slow-opening	Natural	5.0–7.0	–	3.5	–		3.0–5.0
	LP	12.0–14.0	–	11.0	–		8.0–12.0
Step-opening	Natural	5.0–7.0	0.9	3.5	–		3.0–5.0
	LP	12.0–14.0	2.2	11.0	–		8.0–12.0

Table 7. Pressure regulator specification (pressures in kPa)

				Outlet Pressure
		Nominal inlet	Nominal factory setting			Setting range
Model	Type of gas	pressure range	Step	Full rate		Step	Full rate
Standard, slow-opening	Natural	1.2–1.7	–	0.9	–		0.7-1.2
	LP	2.9–3.9	–	2.7	–		2.0-3.0
Step-opening	Natural	1.2–1.7	0.2	0.9	–		0.7-1.2
	LP	2.9–3.9	0.9	2.7	–		2.0-3.0

Check Safety and Shutdown Performance

WARNING

Fire or explosion hazard. Can cause property damage, severe injury or death.

Perform the safety shutdown test any time work is done on a gas system.

Read steps 1–7 below before starting and compare to the safety shutdown or safety lockout tests recommended for the intermittent pilot (IP) module. Where they differ, use the procedure recommended for the module.

1.Turn gas supply off.

2.Set the thermostat or the controller above room temperature to call for heat.

3.Watch for spark at the pilot burner either immediately or following prepurge. See IP module specifications.

4.If the module has timed ignition, time the length of spark operation. See IP module specifications.

5.After the module locks out, open the gas control knob and ensure there is no pilot or main burner gas flow. With modules that continue to spark until pilot lights or system is shut down manually, the pilot should light when gas control knob is opened.

6.Set the thermostat below room temperature and wait one minute.

7.Operate the system through one complete cycle to ensure all controls operate properly.

Regular preventive maintenance is important in applications that place a heavy load on system controls, such as in the commercial cooking and agricultural and manufacturing industries, because:

•In many such applications, particularly commercial cooking, the equipment operates 100,000 to 200,000 cycles per year. 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 checkout of the gas control as outlined under “STARTUP AND CHECKOUT” on page 4, and the control system as described in the appliance manufacturer’s literature. Maintenance frequency must be determined individually for each application. Some considerations are:

•Cycling frequency. Appliances that might 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.

MAINTENANCE

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 the control is reassembled properly and perform the gas leak test.

The gas control should be replaced if:

•It does not perform properly on checkout or troubleshooting.

•It is likely to have operated for more than 200,000 cycles.

•The gas control knob is hard to turn or push down or it fails to pop back up when released.

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