Mechanical (cont’d) – Reznor VR Unit Installation Manual User Manual
Page 23
Form I-VR, P/N 205202 R13, Page 22
6. Mechanical
(cont’d)
Gas Valve Outlet
Pressure Settings
Measuring valve outlet gas pressure cannot be done until the heater is in oper-
ation. It is included in the steps of the “Check-Test-Start” procedure in Para-
graph 8. The following warnings and instructions apply.
Before attempting to measure or adjust the valve outlet gas pressure, the inlet
(supply) pressure must be within the specified range for the gas being used both
when the heater is in operation and on standby. Incorrect inlet pressure could
cause excessive outlet gas pressure immediately or at some future time.
Instructions for Checking Valve Outlet Pressure:
1) With the manual valve (on the combination valve) positioned to prevent flow
to the main burners, connect a manometer to the 1/8” pipe outlet pressure tap
in the valve.
NOTE: A manometer (fluid-filled gauge) is recommended rather
than a spring type gauge due to the difficulty of maintaining calibration of a
spring type gauge.
2) Open the valve and operate the heater. Measure the outlet gas pressure.
Adjustment to the factory preset regulator is rarely necessary.
Valve Outlet Pressure Settings
BTUH Input
Gas Type Outlet Pressure
50,000 - 150,000
Natural
3.5” w.c.
175,000 - 200,000 Natural
5” w.c.
50,000 - 200,000 Propane
10” w.c.
WARNING: All components of the gas supply system must be leak-tested prior to
placing equipment in service. NEVER TEST FOR LEAKS WITH AN OPEN FLAME. See
Hazard Levels, page 2.
6.3 Gas Piping and Pressures (cont’d)
Use a joint compound that is resistant to propane gas at all connections.
Test all gas lines using a leak-detecting solution.
THE GAS SUPPLY NIPPLE MUST BE
PARALLEL TO THE HEATER MOVEMENT
VERTICAL
(AS SHOWN AT LEFT)
ALTERNATE
POSITIONS
OKAY
END VIEW
HEATER MOVEMENT
3” (76mm) MAX.
DISPLACEMENT
12”
(305 mm)
WARNING: CONNECTOR MUST BE INSTALLED IN “ ” CONFIGURATION.
Use a 36” (914mm) long connector of 3/4” nominal ID with this heater.
FIGURE 23 - Gas Connection
Installation Requirements
CORRECT
POSITIONS
INCORRECT POSITIONS
HEATER MOVEMENT
WRONG
HEATER MOVEMENT
WRONG
HEATER MOVEMENT
WRONG
HEATER MOVEMENT
WRONG