Desa VML27NR Operation And Installation Manual page 16

inStALLAtion
Continued
WARNING: Use pipe joint
sealant that is resistant to liquid
petroleum (LP) gas.
We recommend that you install a sediment trap in
supply line as shown in Figure 18. 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
gas control. Hold gas control
with wrench when connecting it
to gas piping and/or fittings.
CSA Design-
Certified
Equipment Shutoff
Valve With 1/8"
NPT Tap*
Approved
Flexible Gas
Hose (if allowed
by local codes)
Gas Control
Figure 18 - Gas Connection
* Purchase the optional CSA design-certified
equipment shutoff valve from your dealer. See
Accessories, page 29.
** Minimum inlet pressure for purpose of input
adjustment.
16
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)
3" Minimum
Cap Pipe Tee
Nipple Joint
Sediment Trap
www.desatech.com
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: Make sure exter-
nal regulator has been installed
between propane/LP supply
and heater. See guidelines un-
der Connecting to Gas Supply,
page 14.
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 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.
111115-01F