INSTALLATION
Continued
Installation must include equipment shutoff valve, union and plugged 1/8" NPT tap. Locate NPT tap within reach for test gauge hook up. NPT tap must be upstream from heater (see Figure 13).
IMPORTANT: Install an equipment shutoff valve in an accessible location. The equipment shutoff valve is for turning on or shutting off the gas to the appliance.
Apply pipe joint sealant lightly to male NPT threads. This will prevent excess sealant from going into pipe. Excess sealant in pipe could result in clogged heater valves.
WARNING: Use pipe joint sealant that is resistant to liquid petroleum (LP) gas.
Install sediment trap in supply line as shown in Figure 13. Locate sediment trap where it is within reach for cleaning. Locate sediment trap where trapped matter is not likely to freeze. A sediment trap traps moisture and contaminants. This keeps them from going into heater controls. If sediment trap is not installed or is installed wrong, heater may not run properly.
IMPORTANT: Hold the pressure regulator with wrench when connecting it to gas piping and/or fittings. Do not over tighten pipe connection to regulator. The regulator body could be damaged.
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 10.
3/8" NPT
Pipe
Nipple
Ground
Joint
Union
Pressure
Regulator
Heater Cabinet
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 |
Equipment
Shutoff 
Valve *
Natural Gas |
|
|
|
From Gas |
|
|
|
Meter (7" W.C. |
|
|
|
to 10.5" W.C. | 3" |
|
|
Pressure) |
|
|
|
Min. |
| ||
Propane/LP |
| ||
|
|
| |
|
|
| |
From External |
|
|
|
Regulator |
|
|
|
(11" W.C. to 14" | |||
W.C. Pressure) |
|
|
|
Tee Joint
Reducer 
Bushing to 
1/8" NPT
1/8" NPT Plug Tap
Cap Pipe Tee Nipple Joint
Sediment Trap
Test Gauge Connection*
| 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. |
Figure 13 - Gas Connection
*A CSA
6. | Reconnect heater and equipment shutoff |
| valve to gas supply. Check reconnected fit- |
| tings for leaks. |
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