Daikin DRG0361DL00001S Service Instructions Manual page 31

SYSTEM OPERATION
The minimum supply pressure should not vary from that
shown in the table above because this could prevent the
unit from having dependable ignition. In addition, gas
input to the burners must not exceed the rated input
shown on the rating plate. Overfiring of the unit could
result in premature heat exchanger failure.
Piping
IMPORTANT NOTE: To avoid possible unsatisfactory
operation or equipment damage due to under firing of
equipment, do not undersize the natural/propane gas
piping from the meter/tank to the unit. When sizing a
trunk line, include all appliances on that line that could
be operated simultaneously.
The gas line installation must comply with local codes, or
in the absence of local codes, with the latest edition of the
National Fuel Gas Code NFPA 54 / ANSI Z223.1.
Natural Gas Connection
Natural Gas Capacity of Pipe
in Cubic Feet of Gas Per Hour (CFH)
Length of
Nominal Black Pipe Size (inches)
Pipe in Feet
1/2
10 132
20 92
30 73
40 63
50 56
60 50
70 46
80 43
90 40
100 38
Pressure= .50 PSIG or less and Pressure Drop of 0.3" W.C.
(Based on 0.60 Specific Gravity Gas)
CFH =
Heating Value of Gas (BTU/Cubic Foot
Refer to the Proper Piping Practice drawing for the general
layout at the unit. The following rules apply:
1. Use black iron pipe and fittings for the supply piping.
The use of a flex connector and/or copper piping is
permitted as long as it is in agreement with local
codes.
2. Use pipe joint compound on male threads only. Pipe
joint compound must be resistant to the action of the
fuel used.
3. Use ground joint unions.
4. Install a drip leg to trap dirt and moisture before it can
enter the gas valve. The drip leg must be a minimum
of three inches long.
3/4 1 1 1/4 1 1 /2
278 520 1050 1600
190 350 730 1100
152 285 590
130 245 500
115 215 440
105 195 400
96 180 370
90 170 350
84 160 320
79 150 305
BTUH Furnace Input
5. Use two pipe wrenches when making connection to
the gas valve to keep it from turning.
6. Install a manual shut-off valve in a convenient location
(within six feet of unit) between the meter and the
unit.
7. Tighten all joints securely.
8. The unit must be connected to the building piping by
one of the following methods:
• Rigid metallic pipe and fittings
• Semirigid metallic tubing and metallic fittings
(Aluminum alloy tubing must not be used in
exterior locations).
• Listed gas appliance connectors used in
accordance with the terms of their listing that are
completely in the same room as the equipment.
Always use a new listed connector.
• In the prior two methods above the connector
or tubing must be protected from physical and
thermal damage. Aluminum alloy tubing and
connectors must be coated to protect against
external corrosion when in contact with masonry,
plaster or insulation or are subject to repeated
wettings by liquids (water - not rain water,
detergents or sewage).
980
760
670
610
560
530
490
460
MANUAL
SHUT-OFF
NOTE: The unit gas supply entrance is factory sealed with
plugs. Keep plugs in place until gas supply is ready to be
installed. Once ready, replace the plugs with the supplied
grommets and install gas supply line.
BURNER
DOOR
DRIP
GROUND
LEG
JOINT UNION
Proper piping practice
31