Centurion Water Heater- Edge [ii]: Install-Operation-Service
SECTION 2: INSTALLATION
OMM-0153_A
• 8/25/2022 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page 23 of 131
Prior to installation, all pipes should be de-burred and internally cleared of any scale, metal
chips or other foreign particles. Do
NOT
install any flexible connectors or unapproved gas
fittings. Piping must be supported from the floor, ceiling or walls only and must not be supported
by the unit.
A suitable piping compound, approved for use with natural gas, should be used. Any excess
must be wiped off to prevent clogging of components.
To avoid unit damage when pressure testing gas piping, the unit must be isolated from the gas
supply piping. A thorough leak test of all external piping must be performed using a soap and
water solution or suitable equivalent. The gas piping used must meet all applicable codes.
2.8.1 Gas Supply Specifications
CENTURION Water Heaters require a stable natural gas input pressure. It must comply with the
allowable gas inlet pressure range in the table below:
Allowable Gas Inlet Pressure for Standard Gas Trains
STANDARD GAS TRAINS
Model
NATURAL GAS
Minimum
Maximum
CEN2000
4.0” W.C. (1.00 kPa)
14.0” W.C. (3.49 kPa)
DBB GAS TRAINS
CEN2000
4.5” W.C. (1.12 kPa)
14.0” W.C. (3.49 kPa)
Gas pressure must be measured when the unit is in operation at full fire. Measure the gas
pressure with a manometer at the NPT ball valve provided at the SSOV inlet. In a multiple
Water Heater installation, gas pressure must initially be set for single unit operation, and then
the remaining units must be staged on at full fire, to insure gas pressures never falls below the
supply gas pressure when the single unit was firing.
All CENTURION models have a low supply gas pressure switch in the gas train to prevent
operation if incoming gas pressure is insufficient.
2.8.2 External Gas Supply Regulator
An external gas pressure regulator is required on the gas inlet piping under most conditions
(see, below). Regulators must conform to the specifications in the following table:
Lock-Up Regulator Sizing
Model
Required Volume
CFH
(m
3
/HR)
CEN2000
2000
–
2300
(56.6
–
65.1)
An external lock-up type regulator
MUST
be installed downstream of the isolation valve at all
installations where gas supply pressure will
exceed
14.0
” W.C. (3.49 kPa)
.
C A U T I O N !
PVI units must be isolated from the system when leak testing.
Drip legs are typically required at the gas supply of each unit to prevent any dirt, weld slag, or
debris from entering the
unit’s gas train inlet pipe. When multiple units are installed, some
utilities and local codes require a full-size drip leg on the main gas supply line in addition to the
drip leg at each unit. The bottom of the gas drip leg(s) should be removable without
disassembling any gas piping. The weight of the gas pipe must not be supported from the
bottom of the drip leg. The drip leg(s) must not be used to support any or part of the gas piping.
