GAS PRESSURE REGULATOR

The gas pressure regulator is preset at 4.0 in. WC throughout for natural gas, and 10.5 in. WC. for propane gas. The pressure at the gas valve, taken with a manometer, should be about 4.0 in. WC natural gas (3.0 in. WC for Low NOx) and 10.5 in. WC propane gas. If an adjustment is needed, remove seal

and turn adjustment screw clockwise to increase

pressure or counter-clockwise to decrease pres- sure.

NOTE: Low NOx gas valves are non-adjustable; set- ting was made at the manufacturer (Invensys/Robertshaw).

MANOMETER

MANUAL

SHUT-OFF

VALVE

GAS PRESSURE

TEST AT GAS VALVE

ELECTRONIC IGNITION GAS VALVES-CONTINUED

Gas Pressure

Adjustment

Robertshaw 7200

Robertshaw 7000 BDER

(Heater Model 206)

(Heater Models 266-336)

Gas Pressure

Adjustment

Robertshaw 7000 DERHC

(Heater Model 406)

Non-Adjustable

Gas Valve

GAS PRESSURE ADJUSTMENT LOCATIONS

MILLIVOLT GAS VALVES

Gas Pressure

Adjustment

Fig # 9263

Robertshaw 7000

(Heater Models 206-406)

ELECTRONIC IGNITION GAS VALVES

Gas Pressure

Adjustment

Honeywell VR8304 (Heater Models 206- 406)

Fig # 9263

Robertshaw 7000 BDERF

(Heater Models 207-407)

PIPE SIZING FOR GAS CONNECTIONS

Maximum Equivalent Pipe Length

Natural Gas 1000 BTU/FT3 0.60

Specific Gravity @ 0.5 in. WC Pressure Drop

Propane Gas 2500 BTU/FT3 1.53

Specific Gravity @ 0.5 in. WC Pressure Drop

Input

3/4”

1”

1-1/4”

1-1/2”

Model (KBTU) N P N P N P N P

206/207 199.5 25 60 90 215 360

266/267 266.0 15 35 50 125 210 480 445

336/337 332.5 10 20 30 80 140 320 290

406/407 399.0 15 20 55 95 225 215 480

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Raypak 336A, 406A, 206A, 407A GAS Pressure Regulator, GAS Pressure Adjustment Locations, Pipe Sizing for GAS Connections