Desa VYM27NRPR - Manual (Page 12)

110398-01A
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12
INSTALLATION
Connecting To Gas Supply (Cont.)
Checking Gas Connections
INSTALLATION
Continued
We recommend that you install sediment trap in supply line as
shown in Figure 14. Locate sediment trap where it is within reach for
cleaning. Install in piping system between fuel supply and heater.
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.
CAUTION: Avoid damage to control. Hold fitting
with wrench when connecting it to gas piping and/or
fittings.
* Purchase the optional CSA design-certified equipment shutoff
valve from your dealer. See Accessories, page 24.
** Minimum inlet pressure for purpose of input adjustment.
Figure 14 - Gas Connection
Gas Control
3" Minimum
CSA Design-Certified
Equipment Shutoff Valve
With 1/8" NPT Tap*
Approved Flexible
Gas Hose (if allowed
by local codes)
Cap Pipe Tee
Nipple Joint
Sediment Trap
Natural Gas
From Gas Meter (5"
W.C.** to 10.5" W.C.
Pressure)
Propane/LP Gas
From External
Regulator
(11" W.C.** to 14"
W.C. Pressure)
WARNING: Test all gas piping and connections
for leaks after installing or servicing. Correct all leaks
at once.
CHECKING GAS CONNECTIONS
WARNING: Never use an open flame to check for
a leak. Apply a noncorrosive leak detection fluid to all
joints. Bubbles forming show a leak. Correct all leaks
at once.
CAUTION: For propane/LP gas, make sure exter-
nal regulator has been installed between propane/LP
supply and heater. See guidelines under
Connecting
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 (con-
trol valve) and equipment shutoff valve from gas supply pip-
ing 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 sup-
ply tank valve for propane/LP gas, or opening main gas valve lo-
cated 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 gas joints. Bubbles forming show a leak.
5. Correct all leaks at once.
6. Reconnect heater and equipment shutoff valve to gas supply.
Check reconnected fittings for leaks.
Test Pressures Equal To or Less Than 1/2 PSIG (3.5 kPa)
1. Close equipment shutoff valve (see Figure 15).
2. Pressurize supply piping system by either opening propane/LP sup-
ply tank valve for propane/LP gas, or opening main gas valve lo-
cated on or near gas meter for natural gas, or using compressed air.
3. Check all joints from propane/LP supply tank to equipment
shutoff valve (see Figure 15). Apply a noncorrosive leak de-
tection fluid to gas joints. Bubbles forming show a leak.
4. Correct all leaks at once.
Pressure Testing Heater Gas Connections
1. Open equipment shutoff valve (see Figure 15, page 12).
2. Open main gas valve located on or near gas meter for natural
gas or 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 control valve
(see Figure 16 or 17, page 13). Apply a noncorrosive leak de-
tection fluid to gas joints. Bubbles forming show a leak.
5. Correct all leaks at once.
6. Light heater (see Operating Heater, pages 14 through 16).
Check all other internal joints for leaks.
7. Turn off heater (see To Turn Off Gas to Appliance, page 15).
ON
POSITION
OFF
POSITION
Figure 15 - Equipment Shutoff Valve
Open
Closed
Equipment
Shutoff
Valve