Reznor RXH (Outdoor PreevA) Unit Installation Manual - Manual (Page 15)

Form I-RDH/REH/RHH/RXH (12-14), P/N 215210 R14, Page 15
5.3 Rigging and
Lifting
NOTE: Apply gasketing to
the roof curb prior to lifting
the unit and setting it on the
curb.
1. Position curb cross rails and curb side rails as illustrated in FIGURE 8, page 12.
Using the hardware provided, join the corners as illustrated in the corner detail
( FIGURE 9).
2. Check the assembly for squareness. Adjust the roof curb so that the diagonal
measurements are equal within a tolerance of ±1/8” (3mm).
3. Level the roof curb. To ensure proper condensate drainage and a weathertight
seal between the system curb cap and the roof curb, the roof curb must be leveled
in both directions with no twist end to end. Shim level as required and secure curb
to roof deck before proceeding with flashing.
4. Install field-supplied flashing.
5. Before placing the unit on the curb, apply furnished 1/4” x 1-1/4” foam sealant tape
to top surface of curb, making good butt joint at corners. The unit must be sealed
to the curb to prevent water leakage into the curb area due to blown rain and
capillary action.
6.1.1 Gas Supply and
Connections
6.0 Mechanical 6.1 Gas Piping and Pressures - Models RDH and RHH
NOTE: Gas conversion kits
are available for changing
units with 1-stage and
2-stage gas controls (Option
AG1, AG2, AG3, AG15, and
AG16) from natural gas
to propane or propane to
natural gas.
Gas conversion kits do
not apply to a heater with
a 2-speed venter control
system (Option AG8,
AG9, AG9H, AG40, AG58,
AG60, AG61, AG62, DG1,
DG2, DG5, DG6, D12B,
and D12C) or with 8:1
modulation (Options AG58
or D12G).
Contact your distributor,
representative, or the
factory for information.
WARNING: This appliance is equipped for a maximum gas supply pressure of
1/2 psi, 3.5 kPa, or 14 inches water column. NOTE: Supply pressures higher
than 1/2 psi require installation of an additional service regulator external to
the unit.
Pressure Testing Supply Piping:
Test Pressure Above 1/2 PSI: Disconnect the heater and manual valve from the gas
supply which is to be pressure tested. Cap or plug the supply line.
Test Pressure Below 1/2 PSI: Before testing, close the manual valve on the heater.
All piping must be in accordance with requirements outlined in the National Fuel Gas
Code NFPA54/ANSI Z223.1 (latest edition) or CSA B149.1 (latest edition) Natural Gas
and Propane Installation Code. Gas supply piping installation should conform with
good practice and with local codes.
These units for use with natural gas are orificed for gas having a heating value of 1000
(±50) BTU per cubic ft. If the gas at the installation does not meet this specification,
consult the factory for proper orifice.
Pipe joint compounds (pipe dope) shall be resistant to the action of liquefied petroleum
gas or any other chemical constituents of the gas being supplied.
Install a ground joint union and manual shutoff valve upstream of the unit control sys-
tem. The 1/8” plugged tapping in the shutoff valve provides connection for supply line
pressure test gauge. The National Fuel Gas Code requires the installation of a trap
with a minimum 3” (76mm) drip leg. Local codes may require a longer drip leg, typically
6” (152mm). See FIGURE 10.
WARNING
All components of a gas supply system must be leak tested prior
to placing the equipment in service. NEVER TEST FOR LEAKS
WITH AN OPEN FLAME. See Hazard Levels, page 2.
DANGER
To prevent injury, death, or equipment damage caused by inadequate or improper
rigging, test lift the unit before attempting to place it on a roof. See Hazard Intensity
Levels, page 2.
Lifting holes in the base are provided for rigging. If the circumstances require a rigging
height that is less than 12 feet (3.7M), spreader bars are required. Lift with vertical
force only.
Test lift the unit to be sure that it is secure. Lift the unit slowly, following safe lifting
procedures. Failure to lift by the manufacturer’s instructions could cause damage to
the equipment and/or personal injury or death. The equipment manufacturer is not
responsible for unsafe rigging or lifting procedures.