Lennox International Inc G50UH-60C-110 Honeywell VR8205 Gas Valve with ON/OFF Switch, Revolution

8 - Honeywell VR8205 Gas Valve with ON/OFF Switch

-Move gas valve switch to ON. See figure 27. Honeywell VR8205 Gas Valve with Control Knob - Turn knob on gas valve counterclockwise _ to ON, Do not force. See figure 28,

White Rodgers 36G Gas Valve - Move gas valve switch to ON, See figure 29,

9 - Replace the upper access panel,

10- Turn on all electrical power to to the unit, 11- Set the thermostat to desired setting,

NOTE - When unit is initially started, steps 1 through 11 may need to be repeated to purge air from gas line,

12- If the appliance will not operate, follow the instructions "Turning Off Gas to Unit" and call your service techni- cian or gas supplier,

Turning Off Gas to Unit

1 - Set the thermostat to the lowest setting,

2 - Turn off all electrical power to the unit if service is to be performed,

3 - Remove the upper access panel,

4 - Honeywell VR8205 Gas Valve with ON/OFF Switch

-Move gas valve switch to OFF, See figure 27. Honeywell VR8205 Gas Valve with Control Knob -

Turn knob on gas valve clockwise clio to OFF, Do not force, See figure 28,

White Rodgers 36G Gas Valve - Move gas valve switch to OFF, See figure 29,

5 - Replace the upper access panel. Heating Sequence Of Operation

1 - When thermostat calls for heat, combustion air inducer starts,

2 - Combustion air pressure switch proves combustion air inducer operation. Switch is factory set and requires no adjustment,

3 - After a 15 second prepurge, the hot surface ignitor en- ergizes,

4- After a 20 second ignitor warm-up period, the gas valve solenoid opens,

5 - Gas is ignited, flame sensor proves the flame, and the combustion process continues,

6 - If flame is not detected after first ignition trial, the igni- tion control will repeat steps 3 and 4 four more times before locking out the gas valve ("WATCHGUARD" flame failure mode), The ignition control will then auto- matically repeat steps 3, 4, 5, and 6 after 60 minutes,

7- To interrupt the 60-minute "WATCHGUARD" period, move thermostat from "Heat" to "OFF" then back to

"Heat", Heating sequence then restarts at step 1.

Gas Flow (Approximate)

1 - Operate unit at least 15 minutes before checking gas flow. Determine the time in seconds for one revolu- tions of gas through the meter, A portable LP gas me-

ter (17Y44) is available for LP applications,

2 - Compare the number of seconds and the gas meter size in table 10 to determine the gas flow rate. Multiply

the gas flow rate by the heating value to determine the unit input rate, If manifold pressure is correct and the unit input rate is incorrect, check gas orifices for proper size and restriction,

3 - Remove temporary gas meter if installed,

NOTE - To obtain accurate reading, shut off all other gas

appliances	connected	to meter,
		TABLE 10
	Gas Flow Rate (Ft.'_/Hr.)
Seconds	for 1	Gas	Meter Size
Revolution		1/2 cu ft Dial	1 cu ft Dial
10		180	360
12		150	300
14		129	257
16		113	225
18		100	200
2O		90	180
22		82	164
24		75	150
26		69	138
28		64	129
3O		60	120
32		56	113
34		53	106
36		50	100
38		47	95
4O		45	90
42		43	86
44		41	82
46		39	78
48		38	75
5O		36	72
52		35	69
54		33	67
56		32	64
58		31	62
6O		30	60

Gas Pressure

1 - Check the gas line pressure with the unit firing at maxi- mum rate. A minimum of 4.5 in, w.c. for natural gas or 11,0 in, w,c, for LP/propane gas should be maintained, 2- After the line pressure has been checked and ad- justed, check the manifold pressure. A natural gas to LP/propane gas changeover kit is required to convert the unit, Manifold pressure for all units fueled by natu-

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