Desa CBN20T EN - Manual (Page 13)

www.desatech.com 107882-01K 13
INSTALLATION
Continued
* A CSA design-certified equipment shutoff valve
with 1/8" NPT tap is an acceptable alternative to
test gauge connection. Purchase the optional CSA
design-certified equipment shutoff valve from your
dealer. See Accessories, page 23.
Figure 15 - Gas Connection
Pressure
Regulator
Test Gauge Connection*
Tee
Joint
Pipe
Nipple
Cap
3/8" NPT
Pipe Nipple
Heater
Cabinet
Sediment
T
rap
Equipment
Shutoff
Valve *
3"
Minimum
Natural Gas
From Gas Meter
(4" W.C. to 10.5"
W.C. Pressure)
Propane/LP
From External
Regulator
(11" W.C. to 14"
W.C. Pressure)
Ground Joint
Union
Note: Burner bracket
not shown for clarity
CHECKING GAS CONNECTIONS
WARNING: Test all gas piping
and connections, internal and
external to unit, for leaks after
installing or servicing. Correct
all leaks at once.
WARNING: Never use an
open flame to check for a leak.
Apply a noncorrosive leak detec-
tion fluid to all joints. Bubbles
forming show a leak. Correct all
leaks at once.
CAUTION: For propane/LP
gas, make sure external regula-
tor has been installed between
propane/LP supply and heater.
See guidelines under Connect-
ing to Gas Supply, page 12.
PRESSURE TESTING GAS SUPPLY
PIPING SYSTEM
Test Pressures In Excess Of 1/2 PSIG
(3.5 kPa)
1. Disconnect appliance with its appliance main
gas valve (control valve) and equipment
shutoff valve from gas supply piping system.
Pressures in excess of 1/2 psig will damage
heater regulator.
2. Cap off open end of gas pipe where equipment
shutoff valve was connected.
3. Pressurize supply piping system by either
opening propane/LP supply tank valve for
propane/LP gas or opening main gas valve
located on or near gas meter for natural gas,
or using compressed air.
4. Check all joints of gas supply piping system.
Apply a noncorrosive leak detection fluid to
all joints. Bubbles forming show a leak.
5. Correct all leaks at once.
6. Reconnect heater and equipment shutoff
valve to gas supply. Check reconnected fit-
tings for leaks.
Test Pressures Equal To or Less Than 1/2
PSIG (3.5 kPa)
1. Close equipment shutoff valve (see Figure 16).
2. Pressurize supply piping system by either
opening propane/LP supply tank valve for
propane/LP gas or opening main gas valve
located on or near gas meter for natural gas,
or using compressed air.
3. Check all joints from gas meter for natural
gas (see Figure 17, page 14) or propane/LP
supply tank for propane/LP gas, to equipment
shutoff valve (see Figure 18, page 14). Apply a
noncorrosive leak detection fluid to all joints.
Bubbles forming show a leak.
4. Correct all leaks at once.
Figure 16 - Equipment Shutoff Valve
Equipment
Shutoff Valve
Open
Closed
Tee Joint
Reducer
Bushing to
1/8" NPT
1/8" NPT
Plug Tap