![background image](http://html1.mh-extra.com/html/desa/cbn20t/cbn20t_installation-manual_2485752013.webp)
www.desatech.com
13
107882-01M
INSTALLATION
Continued
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 11.
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
Figure 18 - Checking Gas Joints for
Propane/LP Gas
Figure 16 - Equipment Shutoff Valve
Propane/LP
Supply Tank
Open
Closed
Equipment
Shutoff Valve
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
or propane/LP supply tank for propane/LP gas,
to equipment shutoff valve (see Figure 17 or 18).
Apply a noncorrosive leak detection fluid to
all joints. Bubbles forming show a leak.
4. Correct all leaks at once.
PRESSURE TESTING HEATER GAS
CONNECTIONS
1. Open equipment shutoff valve (see Figure 16).
2. For natural gas open main gas valve located
on or near gas meter. For propane/LP gas open
propane/LP supply tank valve.
3. Make sure control knob of heater is in the OFF
position.
4. Check all joints from equipment shutoff valve
to thermostat gas valve (see Figure 17 or 18).
Apply a noncorrosive leak detection fluid to
all joints. Bubbles forming show a leak.
5. Correct all leaks at once.
6. Light heater (see
Operating Heater
, page 14).
Check all other internal joints for leaks.
7. Turn off heater (see
To Turn Off Gas to Appli-
ance
, page 15).
8. Replace front panel.
Figure 17 - Checking Gas Joints for
Natural Gas
Gas
Meter
Thermostat
Gas Valve
Equipment
Shutoff Valve
Thermostat
Gas Valve
Equipment
Shutoff Valve