Daikin DBG Series Service Instructions Manual page 12

SYSTEM OPERATION
GAS SUPPLY PIPING
T
O PREVENT PERSONAL INJURY OR DEATH DUE TO IMPROPER
, ,
INSTALLATION ADJUSTMENT
. F
REFER TO THIS MANUAL OR ADDITIONAL ASSISTANCE OR
,
INFORMATION CONSULT A QUALIFIED INSTALLER
.
THE GAS SUPPLIER
IMPORTANT NOTE: This unit is factory set to operate on
natural gas at the altitudes shown on the rating plate.
T
O PREVENT PROPERTY DAMAGE
EITHER USING PROPANE GAS ALONE OR AT HIGHER ALTITUDES
AND INSTALL THE PROPER CONVERSION KIT
RESULT IN UNSATISFACTORY OPERATION AND
H
IGH ALTITUDE KITS ARE FOR
C
APPROVED FOR USE IN ANADA
The rating plate is stamped with the model number, type of
gas and gas input rating. Make sure the unit is equipped to
operate on the type of gas available. Conversion to propane
(LP) gas is permitted with the use of the factory authorized
conversion kit (see the unit Spec Sheet Manual for the appro-
priate kit). For High Altitude derates, refer to the latest edition
of the National Fuel Gas Code NFPA 54/ANSI Z223.1.
INLET GAS PRESSURE
NATURAL Min. 5.0" W.C., Max. 10.0" W.C.
PROPANE Min. 11.0" W.C., Max. 14.0" W.C.
Inlet Gas Pressure Must Not Exceed the Maximum Value Shown in Table
Above.
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 opera-
tion 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 rating plate is stamped with the model number, type of
gas and gas input rating. Make sure the unit is equipped to
operate on the type of gas available. 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.
12
Natural Gas Connection
WARNING
,
ALTERATION SERVICE OR MAINTENANCE
,
SERVICE AGENCY OR
WARNING
,
PERSONAL INJURY OR DEATH WHEN
( ). F
S AILURE TO DO SO CAN
/
OR EQUIPMENT DAMAGE
U.S. I
NSTALLATIONS ONLY AND ARE NOT
.
Length of
Pipe in Feet
10
20
,
30
40
50
60
70
80
90
100
Pressure= .50 PSIG or less and Pressure Drop of 0.3" W.C.
(Based on 0.60 Specific Gravity Gas)
,
CFH =
OBTAIN
.
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.
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
• 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).
Natural Gas Capacity of Pipe
in Cubic Feet of Gas Per Hour (CFH)
Nominal Black Pipe Size (inches)
1/2 3/4 1
132 278 520
92 190 350
73 152 285
63 130 245
56 115 215
50 105 195
46 96 180
43 90 170
40 84 160
38 79 150
BTUH Furnace Input
Heating Value of Gas (BTU/Cubic Foot
1 1/4 1 1 /2
1050 1600
730 1100
590 980
500 760
440 670
400 610
370 560
350 530
320 490
305 460