Trane 4YCC4024A1060A Installer's Manual page 20

S S t t e e p p 4 4 — — U U n n i i t t I I n n s s t t a a l l l l a a t t i i o o n n
Table 7. Natural Gas Only
TABLE OF CUBIC FEET PER HOUR OF GAS FOR VARIOUS PIPE
SIZES AND LENGTHS
PIPE
SIZE
(inch) 10 20
1/2
132 92
3/4
278 190
1 520 350
1–1/4
1050 730
THIS TABLE IS BASED ON PRESSURE DROP OF 0.3 INCH W.C.
AND 0.6 SP.GR. GAS
G G a a s s P P r r e e s s s s u u r r e e S S e e t t - - u u p p P P r r e e c c a a u u t t i i o o n n s s
I I m m p p o o r r t t a a n n t t : : Do not connect gas piping to the unit until a
line pressure test has been completed. This
unit should never be exposed to gas line
pressure in excess of 14 inches water
column (1/2 PSIG). The furnace and its
equipment shutoff valve must be
disconnected from the gas supply piping
system during any pressure testing of that
system at test pressures in excess of 1/2
psi.
The furnace must be isolated from the gas supply
piping system by closing its individual manual shut-off
valve during any pressure testing of the gas supply
piping system at test pressures less than or equal to 1/2
psig (3.48 kPa).
G G a a s s S S u u p p p p l l y y L L i i n n e e P P r r e e s s s s u u r r e e
Before connecting the unit to the gas supply line, be
sure to determine the gas pressure in the line.
If the gas supply pressure is excessive (above 14 inches
water column or 1/2 psig), install a pressure regulator
either at the supply source or in the branch circuit
serving the unit. Once the regulator is installed, set it to
provide a pressure of 7 inches water column with the
unit operating and no greater than 14 inches water
column with the unit not firing.
N N o o t t e e : : Gas pressure in excess of 14 inches water
column (1/2 psig) may damage the regulator,
while improper regulation may result at
pressures lower than 5.5 inches water column at
the unit inlet.
If the supply line pressure is below the minimum
supply pressure indicated on the unit nameplate,
contact the gas supply company.
Follow these steps to complete the installation of the
unit gas piping. See Table 8, p. 20
N N o o t t e e : : The shut-off gas cock must be installed outside
of the unit and should meet the specifications of
all applicable national and local codes.
20
30 40 50 60
73 63 56 50
152 130 115 105
285 245 215 195
590 520 440 400
Table 8. Gas Pipe
1/8" N.P.T.PLUGGED
ACCESS FOR TEST
GAUGE CONNECTION
70
FROM
GAS SUPPLY
46
96
180
FIELD SUPPLIED MAIN
GAS VALVE, MUST BE
370
INSTALLED BY DEALER
OUTSIDE OF UNIT.
N N o o t t e e : : The shut-off gas cock must be installed outside
of the unit and should meet the specifications of
all applicable national and local code.
1. Install a ground union joint downstream of the
shut-off cock. This joint must also be installed
outside of the unit.
2. Install a drip leg at least six (6) inches in depth next
to the union as shown in . This drip leg is required
to collect any sediment that may be deposited in
the line.
3. Before connecting the piping circuit to the unit,
bleed the air from the supply line and then cap or
plug the line and test the pressure at the tapped
shut-off cock. The pressure reading should not
exceed 13.8 inches water column.
4. Using an appropriate backup wrench on the gas
valve inlet boss, connect the gas piping to the unit.
Check the completed piping for leaks using a soap
and water solution or the equivalent.
5. After installation of the gas pipe in the unit, the pipe
opening should be closed with the filler/barrier plug
provided.
V V e e r r i i f f y y M M a a n n i i f f o o l l d d P P r r e e s s s s u u r r e e
Check the manifold pressure at the unit gas valve. Do
not exceed the recommended pressure shown on the
unit nameplate. See for connections. Refer to Manifold
Pressure Check and Adjust in the following Step 5-Unit
Startup section if adjustment is needed.
I I n n p p u u t t C C h h e e c c k k a a n n d d A A d d j j u u s s t t m m e e n n t t
1. Make sure all gas appliances are off except the
furnace.
2. Clock the gas meter with the furnace operating
(determine the dial rating of the meter) for one
revolution.
3. Match the "Sec" column in the Gas Flow (in cfh)
Table 9, p. 21
4. Read the "Flow" column opposite the number of
seconds clocked.
5. Table 9, p. 21
1, 1/2, or 5 Cu. Ft. dials use the following
conversions:
DEALER INSTALLED
GROUND UNION
6"
MIN
UNIT
DRIP LEG
(6" MIN)
with the time clocked.
lists values for a 2 cubic foot dial. For
18-EB31D1-1F-EN
TO MAIN
CONTROL
VALVE