Reznor UDBS Unit Installation Manual - Manual (Page 12)

Form I-UDB, P/N 202658 R14, Page 12
6.0 Mechanical
6.1 Gas Piping and
Pressures
6.1.1 Gas Supply and Connections
WARNING
This appliance is equipped for a maximum gas supply pressure
of 1/2 psi, 3.5 kPa, or 14 inches water column. Supply pressure
greater than 1/2 psi requires installation of an additional lockup-
type service regulator external to the unit.
WARNING: PRESSURE TESTING SUPPLY PIPING
Test Pressures Above 1/2 PSI: Disconnect the heater and manual valve
from the gas supply line which is to be tested. Cap or plug the supply line.
Test Pressures 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 ANSI/Z223.1a (latest edition) or CSA-B149.1 and B149.2 (See Paragraph 2).
Gas supply piping installation should conform with good practice and with local codes.
Support gas piping with pipe hangers, metal strapping, or other suitable material; do
not rely on the heater to support the gas pipe.
The heater is orificed for operation with natural gas having a heating value of 1000 (±
50) BTU per cubic ft or propane gas with a heating value of 2500 (± 100) BTU per cubic
ft. If the gas at the installation does not meet these specifications, consult the factory
for proper orificing.
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, as shown in FIGURE 9. Installation of a trap with a minimum 3” (76mm) drip leg
is required.
The unit is equipped with a nipple that extends outside the cabinet. The gas connection
is either 1/2” or 3/4”.
Leak-test all connections by brushing on a leak-detecting solution.
FIGURE 8 - Swivel
Connectors to Suspend the
Heater from 1” Pipe, Option
CK10
If ordered with swivel connectors for 1” pipe, Option CK10, use field-supplied hardware
to attach the swivels at the suspension holes. Suspend with 1” pipe. See FIGURE 8.
Be sure the threaded
swivel connectors are
locked to the hanger
bars as illustrated.
5.0 Hanging the
Heater (cont’d)
Swivel Hanger
Field-supplied
3/8” Hex Nut and
Lock Washer
3/8” Hex Nut
3/8 Lock Washer
®
WARNING
All components of a gas supply system must be leak tested prior to placing equipment in
service. NEVER TEST FOR LEAKS WITH AN OPEN FLAME. Failure to comply could result
in personal injury, property damage, or death.