Installation Instructions
454
SIZE 36
SERIES W
GAS-FIRED AIR CONDITIONER
Installation of the Model 454 Gas Air Con
ditioning unit consists of the following steps:
I. Locating and Mounting the Unit
II. Connecting Chilled Water Lines
III. Making Electrical Connections
IV . Making Gas Connections
V . Charging Systena with Water
VI. Checking the Unit Operation
VII. Adjusting Gas Input
VIII. Balancing the System
DC . Freezing Weather Protection
Each of the above steps is discussed in detail
in this instruction. Read the entire instruc -
tion before starting the installation.
Multiple Chillers and Cooling Coils
bri|ant
I
39454D1
4/25/69
■■1
When it is planned to connect two or more
chillers or coils, additional piping and
electrical information is required and should
be obtained from your Bryant Distributor.
When making multiple chiller installations, it
is recommended that only 454 chillers be
interconnected. The use of other model chil
lers with the 454 in a multiple system should
be avoided.
Operation at Atmospheric Pressure
The chilled water tank on this unit is vented
to the atmosphere; consequently, the chilled
water circuit operates at or near atmospheric
pressure.
Therefore, conventional piping practices for
a closed, pressurized system do not apply
for this unit.
NOTE: When the water chiller is piped to a
boiler as described below, the indoor coil
operates at or near atmospheric pressure
when used for cooling; it may be pressurized
when it is used with the boiler for heating.
Figure 1 - Model 454 Gas Air Conditioner
When this chiller is piped with a boiler to
form a combination heating and cooling sys tern, provisions must be made for a positive
shut-off between the chiller tank and the
boiler.
When the boiler is in operation, the chiller
tank must be by-passed. A sedime:
must be installed
when a common pipe (|oni
and boiler.
When the chiller is i:
of course, should be b;
DO HOT
LOCATING AND M
The unit is designed for outdoor installation.
It may be located at ground level or on a
roof. Consult local or other applicable codes
for information concerning proximity to
property lines, height above roof, obstruc
tions, etc.
36/454
- 2 -
Mounting Base
Clearances
The unit is supported on 3 rails attached to
the bottom of the base. These rails extend
the full width of jiie unit as shown in the
dimensional drawing on page 2 .
The recommended types of mounting bases
for all installations are:
a . Precast concrete lintels .
Use three lintels run the depth of the unit;
one each under the right and left end and one
at the center of the unit.
b, Concrete blocks .
Use a block under each corner plus a block
under each of the two long sides midway be
tween the corner blocks . Arrange the blocks
so that the center rail as well as the front
and back rail is supported.
c . Concrete slab.
Minimum thickness 4 inches.
CAUTION: ALWAYS USE NON-COMBUSTIBLE
MATERIAL FOR THE BASE.
)
The condenser coil is located at the front of
the unit with the condenser air inlet through
the rear fan opening and the discharge
through the louvered front panel.
The minimum clearance between the back of
the unit and a wall is 15 inches. If the over
hang is less than 7 feet above the unit, the
unit must be mounted outside a plumb line
from the eaves of the overhang. The clear
ance on the right and left ends should be a
minimum of 2 feet to provide access for
servicing.
□
AVOID
OPEN
WINDOWS
SLEEPING
QUARTERS
LIVING
AREA
Figure 2 - Locating the Unit
I—I AVOID
u:
GARAGE
ELLS
□
GOOD
location:
AIR
FLOW
r
15
MINIMUM
I. CONNECTING CHILLED WATER LINES
Refer to the following information: 'Multiple Chillers and Cooling Coils", page 1; "Operation
at Atmospheric Pressure, " page 1; and "Cold Weather Protection, " page 8.
TABLE
Nominal
Pipe Size
Inches
Polyethylene Pipe
3/4
1
* Note: Values shown in the above table are for one direction only, and using Bryant water coils. Total length of pipe,
from chiller to coil and return, would be double the values shown. Values apply to single unit installations only.
All distances shown are calculated on the predication that only long elbows are used. Galvanized well head elbows
are used with the polyethylene pipe. When using plastic hose, avoid any sharp bends that would tend to restrict or
stop the flow of water.
Allowable Distance* between Coil Models 404, 405, 406, 407, 408 and Chiller
Size 36
65 ft
280 ft
Bryant Quick Connect
Plastic Hose
Size 36
45 ft
- 3 -
Copper Pipe
Size 36 Size 36
Galvanized Pipe
67 ft
' 260 ft
87 ft
304 ft
36/454
Materials
1 . Chilled Water Piping
a. Use Bryant quick connect plastic hose.
b. Polyethylene pipe - satisfactory substi
tute; use medium density flexible pipe
whose wall thickness approximates
Schedule 40 pipe (Commercial Standard
CS 255-63). Pipe must be made from
virgin material. Do not use pipe manu
factured from re-claimed material.
c . Copper - satisfactory substitute .
d. Brass - satisfactory substitute.
2. Fittings
a. Galvanized - use when possible.
b. Brass - satisfactory substitute .
WATER FLOW RATE
AT VARIOUS EXTERNAL PRESSURES
Table II - Model 36-454
Water Flow Rate
GPM
2.0
3.0
'4.0
5.0
6.0 23.8
7.0
7.5
8.0
9.0
10.0 19.7
11.0 18.6
Pressure External to Unit
Ft Water Std RPM
25.9
25.5
25.0
24.5
23.0
22.5
22.0
21.0
Pipe Length and Diameter
Table I shows the maximum length of pipe of
different diameters that can be used between
the pump discharge and the coil inlet and still
maintain minimum allowable (design) water
flow rate.
1. Multiply table values by two to obtain the
total length of pipe from chiller to coU and
return.
2. Length is measured along the pipe path
and therefore includes vertical distance be
tween the water coil and the chiller.
3. Lengths shown in Table I are based on
using a total of eight well head fittings in the
entire water line (chiller to coil and return).
Lengths are predicated on the use of a Bryant
matching water coil. For greater distances
use larger size pipe.
4. For calculating chilled water pipe size for
coils not listed use friction loss method with
allowance for coil pressure loss. Refer to
coil instructions for pressure loss at design
water flow rate. Refer to Table II showing
available head with standard pump drive. For
additional pump head consult your Bryant
Distributor.
Insulation
1. Insulate both supply and return lines .
2. Material should be of good quality and be
covered with a good vapor barrier. Armaflex
or equivalent is recommended. Use 1/2-inch
wall thickness .(Plastic hose is pre-insulated.)
36/454
Height of Coil above Unit
For the Model 36-454 the maximum vertical
distance from chiller to top of coil is 21 feet.
For greater heights an adjustable water pump
pulley kit is available, Part No. 65070D01.
Water Coil Connections
1. If the cooling coil is used in connection
with a heating unit and the heating unit is not
approved for installation downstream from
the cooling coil, install the cooling coil in
parallel with or downstream from the heating
unit. This will avoid condensation in the heat
ing unit. If the coil and heating unit are in
stalled in parallel, the dampers or other
means used to control flow of air should be
adequate to prevent chilled air from entering
the heating unit; if manually operated, the
dampers shall be equipped with some means
to prevent operation of either unit uiiless the
dampers are in full heat or full cool position.
2. If the coil is located in a warm air stream,
do not connect polyethylene pipe directly to
the coil. Connect a minimum of 24 inches of
copper or galvanized pipe to both the coil in
let and outlet; then connect the polyethylene
pipe to these nipples . Note: not required when
using Bryant quick connect plastic hose.
3. On installations where the water in the
outside piping freezes and the coil is in a
heated air stream, precautions must be taken
to provide for water expansion. The connect
ing polyethylene pipe acts as an expansion
vessel if there is sufficient footage in the
- 4 -
heated space (space not subject to freezing),
The following Table HE shows the minimum
lengths (total inlet and outlet) of polyethylene
piping of various diameters that are required
to provide adequate expansion volume.
TABLE III
Nominal Pipe Size
Inches
3/4 24
1
Length of Polyethylene
Pipe in Feet
Size 36
15
low voltage (24V) wires from the thermostat
control are connected to the low voltage
terminal block in the control box.
Low Voltage Power Supply
Transformer - The air conditioner is not
equipped with a transformer. However, when
a Bryant furnace is used as the air handler
the furnace transformer may be utilized as
the power supply for the low voltage control
circuit in the 454 .
If other than a Bryant furnace is used, you
must use Bryant part number:
If the total polyethylene chilled water line
footage in the heated space is not as long as
the minimum values shown in the table, tee a
vertical pipe of sufficient volume into either
of the coil connections to provide for expan
sion, or drain the lines during freezing,
weather, (see GAC -YAC #1 -100 pages).
Note: No minimum run required when using
Bryant quick connect plastic hose.
III. MAKING ELECTRICAL CONNECTIONS
1. Make all electrical connections in accord
ance with the National Electrical Code and
any local ordinances or codes that might
apply.
2 . Provide a separate power supply for the
air conditioner.
3. Provide a fused disconnect switch within
sight of and not more than 50 feet from the
unit. A 30 amp standard fuse or a 15 amp
Fusetron is suggested.
Use minimum wire of #14 copper wire or #12
aluminum wire. The 115V power supply con
nects into the control box located inside the
service panel on the right side of the unit.
The conduit enters through a knockout located
in the rear of the unit and attaches to the
opening in the bottom of the control box. The
64805D01 115 volt 24 V
The transformer listed is available as an
accessory.
Length of Low Voltage Wire - If the length
of the wire run between the transformer and
the R terminal on the air conditioner exceeds
70 feet it will be necessary to remove the
resistor from the low voltage circuit of the
air conditioner as follows:
1. Remove the wire running from the resis
tor to "R" on the 454 terminal block.
2. Disconnect the pilot wire at the resistor
and connect this wire to "R" on the terminal
block.
IV. MAKING GAS CONNECTIONS
The following recommendations apply to the
installation, tests and operation of appliances
and piping systems for natural and propane
gases:
1. Before making any gas connebtions, refer
to the regulations of the serving gas supplier
and the local building, heating, plumbing or
other codes in effect in the area in which the
installation is made.
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36/454
2. The gas supply pipe enters the unit through
a knockout located in the rear of the unit near
the left side. This unit requires one nipple
that is threaded into the 1 /2 -inch combination
regulator-shutoff valve, see Figure 3 .
3. A wrench-type shutoff valve should be in
stalled in the gas line within sight of, and
convenient to the unit.
Pilot
Light the pilot, using the procedure outlined
on the unit rating plate. However, when
lighting the pilot for the first time, perform (
the following additional steps;
1. If the supply line was not purged prior to
connecting the unit, it will be full of air.
Since it would take a long time to vent this
air through the small pilot port, it is recom -
mended that the pilot supply line be discon
nected at the pilot shutoff valve and the supply
line be allowed to purge until the odor of gas
is detected. Never purge gas lines into the
combustion chamber. Immediately upon de
tection of gas odor, reconnect the pilot supply
tube. Allow 5 minutes to elapse and light the
pilot in accordance with the instructions on
the lighting plate.
2. The pilot flame should be soft blue in
color.
Figure 3 • Gas Connections
4. Joint compound (pipe dope) which is re
sistant to the action of liquefied petroleum
gases should be applied sparingly and only to
the male threads of the joints .
5. Install a drip leg trap in the gas supply
riser leading to the unit. After gas pipe con
nections have been made, purge the lines, as
described below, and check for leakage. Use
a soap and water or other recommended
solution.
6. Never use matches, candles, flame or
other source of ignition to check for leaks.
a. For natural gas this flame should be of
sufficient length to provide good impinge
ment on the unimetal of the Bryant pilot.
The flame should extend upward and above
main burner ports .
3. If the pilot flame does not have the ap
pearance described above, it may be adjusted
at the manual pilot shutoff valve.
a . The valve is equipped with an adjustable
screw. Turn the handle to the full open
position, and remove the screw cap to ex
pose the adjustable screw. Turn adjusting
screw until flame has the desired appear
ance .
b. Replace screw cap.
V. CHARGING THE SYSTEM WITH WATER
Coûtions:
1. Do not run the pump dry.
2. Do not operate the pump when the chiller
or chilled water lines are frozen. Freezing
temperatures, however, will not damage the
pump.
3 . The gas valve on the unit should be closed
when operating the unit during the following
procedures.
35/454
- 6 -
Charge the system with water as follows:
1. Remove the top casing and remove the
cover from the chilled water tank, see
F igure 4.
2. Add tap water until the distributor pan is
covered. A garden hose is useful for this
operation.
3 . Start unit (be sure gas is turned off). Con
tinue to add water until the system is primed
and the water is returning to the chiller tank.
4. Check water piping for leaks throughout
the chilled water system .
5. On the Model 36-454 remove the left side
access panel from unit and remove operating
level drain plug on the side of the chiller
tank.
6. The pump should still be running. When
water ceases to flow from the drain opening,
replace the drain plug.
7. With the water still circulating, add the
bag of chilled water additive by spreading
additive over the distributor pan. The addi
tive is sufficient for chilled water systems
containing up to 9 gallons of water. For sys
tems larger than 9 gallon capacity, add 1/2
package of additive for each 4 -1 /2 gallon
water capacity or fraction thereof. To esti
mate chilled water capacity of system, refer
to Table 4tr-
8. Replace chiller tank cover.
VI. CHECKING THE UNIT OPERATION
j.. Be sure combination gas valve is off. Light
pilot as described on instruction plate.
2. Set thermostat to "cool"; set thermostat
fan switch to "auto"; set thermostat below
room temperature.
3 . Turn on main electric switch to unit.
4. Check indoor fan operation by turning
thermostat fan switch to "on" for continuous
operation. Move thermostat above room tem
perature and observe that the indoor fan re
mains on.
5. To place the system in operation, open the
main manual gas valve, replace all panels,
and set the thermostat at the desired temper
ature .
Figure 4 - Chiller Tank
TABLE IV
Water Capacity
36-454 Chiller
Bryant 1-1/2 ton coil
Bryant 3 ton coil................................................. 1
1 ft 3/4-inch pipe
1 ft 1-inch pipe
....................................................
..................................
................................................
.......................
High Temperature Cut-Off
............................
.... . .6
-3^ X - 3
.03
.05
The high temperature circuit includes a high
temperature control located on the side of the
generator plus a high temperature lockout
(circuit breaker) located in the control box.
If the generator becomes overheated, the
contacts in the high temp control open,
causing the circuit breaker to go into lockout
position. The gas valve closes, the fan and
pumps stop and they will not recycle until
the circuit breaker is reset. To reset the
circuit breaker, push the red button extending
through the bottom of the control box. Be sure
to locate and correct the cause of the high
temp cut-out.
- 7 -
Gallons
36/454
Cycle of Operation
VIII. BALANCING THE SYSTEM
The 36-454 is equipped with a fan/pump motor
control (Bryant Model 821), an auxiliary
SPST relay and a sail switch. The fan/pump
motor control is a single pole, single throw
low voltage switch actuated by a heat motor
(low voltage electric resistance coil fastened
to mono-metal strip next to the switch). When
the thermostat calls for cooling, electric
current energizes the resistance coil in the
Model 821 control and in approximately one
minute the low voltage switch closes, ener
gizing the auxiliary relay which starts the
condenser fan motor and solution pump-water
pump motor. The opening of the gas valve
will be delayed slightly until the condenser
fan is moving a sufficient amount of air
through the unit to activate the sail switch.
On shutdown by the thermostat, the gas valve
will close immediately; however, the balance
of the unit will continue to run for ap
proximately 3 minutes until the low voltage
switch in the Model 821 control opens.
VII. ADJUST GAS INPUT
After the unit is in operation and the input
has been measured and adjusted to agree with
the rating plate requirements, the system
must be balanced.
Any approved method of checking the air flow
over the water coil may be utilized. Refer to
the Bryant Service Manual on Gas Air Con
ditioners for a review of standard methods.
IX. FREEZING WEATHER PROTECTION
Gas Air Conditioner
The unit has built-in freeze protection suf
ficient to protect the chiller and pump.
Chilled Water Pipes
If hard pipe (non-plastic) is used for thé
chilled water lines, it will be necessary to
drain the lines or add antifreeze . The recom
mended antifreeze is Zerex. The chilled
water additive must be used in the same
proportion as indicated in Section V when
antifreeze treatment is required.
The gas input must be checked and adjusted if
necessary to agree with the input shown on
the unit's rating plate.
The natural gas units are equipped with ad
justable gas pressure regulators set at
factory for 4.2 inches w.c. manifold pres
sure .
Check natural
units by the following
gas
method:
1. Measure gas at meter. Be sure all other
gas appliances are turned off. Increase or
decrease input to burners by adjusting the
gas pressure regulator.
Caution: The unit may be run for short
periods with the panel removed. Prolonged
operation with panels removed should not be
attempted.
Chilled Water Coil
Chilled water coils cannot be completely
drained; therefore, if the water coil is sub
ject to freezing temperatures, protect it by
adding antifreeze. The chilled water additive
must be used in the same proportion as indi
cated in Section V when antifreeze treatment
is required.
Operation at Freezing Temperatures
The unit cannot be operated at temperatures
below 40° F.
36/454
- 8 -
THERMOSTAT
AND
TO
FURNACE
FLAGGED WIRES
ON EARLY
PRODUCTION
/UNITS X MAY BE
MARKED F
MODEL 454 CONNECTED TO THE MODEL 394 SERIES B DIRECT DRIVE OR • BELT DRIVE FURNACE
- 9 -
36/454
36/454
- 10 -
THERMOSTAT
AND
SUB BASE
MODEL 884
TO EITHER SUB-BASE
THERMOSTAT 34427D17
AND
SUB BASE 34427D29
CHECK FURNACE LOW VOLTAGE (24V)
WIRING CIRCUIT TO INSURE ALL
CONTROLS (PILOT, LIMIT CONTROLS
AND GAS VALVE) ARE WIRED IN
SERIES BETWEEN THE FURNACE
TRANSFORMER AND THE "W" TERMINAL
OF THE THERMOSTAT.
■ "IMPORTANT”-
TRANSFORMERS MUST BE PHASED
CONNECTING THE MODEL 454 INTO A STANDARD FURNACE
CONTROL CIRCUIT
- 11 -
36/454
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