MartinLogan VENT-FREE FIREPLACE SYSTEMS 33ISDG - Manual (Page 16)

16 23D8036
NOTICE: A qualifi ed gas appliance installer must connect the heater to the gas supply. Consult all
local codes.
IMPORTANT: Loosen the pipe adapter on the fl ex tube before installing to the system piping.
Figure 17 - Gas Connection
To Heater
Valve
Stainless
Flexible Tube
CONNECTING THE GAS
Use new black or steel pipe. Internally tinned copper or copper tubing can be used
per National Fuel Code, section 2.6.3, providing gas meets hydrogen sulfi de limits,
and where permitted by local codes. Gas piping system must be sized to provide
minimum inlet pressure (listed on Data Plate) at the maximum fl ow rate (BTU/Hr).
Undue pressure loss will occur if the pipe is too small.
A manual shutoff valve must be installed upstream of the appliance. Union tee
and plugged
1 /
8
" NPT pressure tapping point should be installed upstream of the
appliance. See Figure 17.
CAUTION
Manual Shutoff
Valve
Pipe
Pipe Coupling
Always use an external regulator for all propane/L.P.G. heaters and high pressure one to two-pound systems only, to
reduce the supply tank pressure to a maximum of 13" w.c. This is in addition to the internal regulator in the heater valve.
CHECK GAS TYPE: The gas supply must be the same as stated on the heater's rating
plate. If the gas supply is different, DO NOT INSTALL THE HEATER. Contact your
dealer for the correct mode.
W
ARNING
Locations that Pressure
Tapping Point May Be
Installed
Gas Supply
Inlet