Bryant 108-451 User Manual

451P

Installation Instructions

GAS-FIRED AIR CONDITIONER

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I

Installation of the Model 108-451 Gas Air Conditioning Absorption Unit consists of the following steps:

I. Locate and Mount Absorption Unit VI. Check-Out and Operation

II. Connect Chilled Water Lines VII. Adjust Gas Input
III. Electrical Connections VIII. Balance System
IV. Gas Connections IX. Purge Non-Condensibles

V. Charge System with Water

Each of the above steps is discussed in detail in this instruction. Read the eiitin
starting installation.

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DO NOT

SIZE 108

SERIES B

39451D8
Rev. 4/12/65

P V

I. LOCATE AND MOUNT ABSORPTION UNIT

The absorption unit may be located at ground level
or on the roof. Consult local codes for information
concerning proximity to property lines, height above
roof, obstructions, etc.

A. MOUNTING BASE

1. Use non-combustible materials.

2. Suggested types of mounting base for ground
installation:

a. Precast concrete lintels.

Use three lintels the depth of unit, one each

urider right and left end of unit and one at center
of unit.

b. Concrete blocks.

Use one block at each corner of unit plus blocks
under the two long sides midway between the
corner blocks.

c. Concrete slab.

Minimum thickness 4 inches.

3. For installation on a roof or other combustible
material leave sufficient clearance between unit
sub-base and roof for proper air circulation. Use
precast concrete lintels or concrete blocks as
described in paragraph 2 above or steel beams.
Check local codes.

B. CLEARANCES

1. Absorption unit should
ance of 2 feet on all sides from any adjacent ob
struction.

2. Avoid locating the unit where hot condenser
discharge air can impinge on nearby obstructions
and mix with the inlet air supply. The condenser air
discharges upward. The unit should be located out
side of the plumb line from any over-hang.

II. CONNECT CHILLED WATER LINES

A. MATERIALS

Refer to section on “Freezing Weather Protection”

at the end of this instruction.

1. Piping

a. Polyethylene Plastic Pipe — use medium

density flexible pipe whose wall thickness ap
proximates Schedule 40 pipe (Commercial Stand
ard CS 197-60). Pipe must be virgin plastic. Do
not use pipe manufactured from re-claimed plas
tic.

b. Copper - satisfactory substitute.

c. Galvanized - satisfactory substitute.

2. Fittings

a. Galvanized - use when possible.

b. Brass - satisfactory substitute.

c. Nylon - satisfactory substitute.

REMOVE

hax&-.a_m.i.aijn.um—clear

WATER OUTLET

ELECTRICAL CONNECTIONS

1"

2 GAS

CONNECTION

Cooling Capacity
Heat Input
Condenser Air Delivery CFM 14,000
Water Flow (minimum required) GPM

Maximum friction loss handled by Chiller Pump
Maximum elevation of coil above chiller
Pump Drive 230 v 60 cy 1 phase HP
Fan Drive 230 v 60 cy 1 phase HP
Minimum Wire Size *
Refrigerant Type
Refrigerant Amount
Approximate Shipping Weight

* Satisfactory where distance, measured along wire path, between unit and connection into main panel does not
exceed 100 ft. Where distances are longer, wire sizes should be increased accordingly.

I" KNOCKOUTS

WATER INLET

1 ”

IZ F.P.T.

108-451
BTUH
BTUH 330,000

Ft. Head
Ft.

AWG 12

LB 55

LB

108,000

22

45
49
1/3

1

717

2200

108/451

2-

Table I

Nominal

Pipe Size

Inches

1

IVa

IV2

* Note: Values shown in above table are for one direction only. The total length of pipe from chiller to coil
and return would be double the above table values. The above table applies to single unit installations only.

B. PIPE LENGTH AND DIAMETER

Polyethylene Pipe

Size 108

48'
272'
610'

Table I shows maximum length of pipe of different
diameters that can be used between the pump dis
charge and the coil inlet and still maintain mini-,
mum allowable (design) water flow rate.

1. Multiply table values by two to obtain the total

length of pipe from chiller to coil and return.

2. Length is measured along the pipe path and
therefore includes vertical distance between the
water coil and the chiller.

Allowable Distance* Between Coil and Chiller

Copper Pipe

Size 108

67'

210'

492'

3. On installations where the outside piping freezes

and the coil is in a heated air stream, precautions
must be taken to provide for water expansion. The
connecting polyethylene plastic pipe acts as an
expansion vessel if there is enough footage of this

pipe in the heated space (space not subject to
freezing). The following table shows the minimum
lengths (total inlet and outlet) of plastic piping of
various diameters that are required for both sizes
of coils to provide adequate expansion volume.

Galvanized Pipe

Size 108

72'

285'
642'

3. Lengths shown in Table I are based on using a
total of eight elbows in the entire water line (chil

ler to coil and return). Lengths are predicated on the

use of a Bryant matching water coil. For greater
distances use larger pipe or add a pump.

C. INSULATION

1. Insulate supply and return lines separately.

2. Material should be of good quality and be covered
with a good vapor barrier. Armaflex or equivalent is
recommended.

Wall thickness:
1/2'' wall thickness - south of 40° N. latitude

Nominal Pipe Size

Inches

1

VA

Length of Plastic Pipe

in Feet

70
40

IV2 29

If the total plastic 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 expansion, or the line should be drained.

3/8" wall thickness - north of 40° N. latitude

D. HEIGHT OF COIL

ABOVE ABSORPTION UNIT

Maximum vertical distance from chiller outlet to top
of coil is 49 feet. For greater heights, a greater
pumping head is required. Increasing the pipe size
will not help.

E. WATER COIL CONNECTIONS

1. If cooling coil is used in connection with heat

ing unit, install cooling coil in parallel with or
downstream of heating unit to avoid condensation in
the heating unit.

2. If coil is located in warm air stream, do not
connect polyethylene pipe directly to coil. Connect
a minimum of 24 inches copper or galvanized pipe
to both the coil inlet and outlet. Then connect the
plastic pipe to these nipples.

III. ELECTRIC CONNECTIONS

1. Make all electric connections in accordance with
the National Electrical Code and any local ordi
nances 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 absorption
unit. Use 35 amp standard fuse.

4. The absorption unit is shipped fully wired from
the factory. Connection of 230V power and low volt
age connection to the thermostat control are re

quired in the field. Before proceeding, inspect
factory wiring for loose connections which may have
resulted during shipment.

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108/451

5. Figures 3 & 4 are the Wiring Diagrams for the
natural gas unit. Figures 5 8s 6 are the Wiring Dia
grams for an LPG unit.

6. Disconnect pump electrical lead at terminal 7
in front control box before energizing unit when
ready to check field wiring.

pump dry.

IV. GAS CONNECTIONS

Do not operate the

Consult local gas company before making any gas
connections. In case of conflict with this instruc
tion, local requirements should be followed.

Before selecting the size and type of pipe that is
to be used for installing the absorption unit, be
sure to check with local gas company for the neces

sary information. The size of the gas pipe to be
used between meter and unit will depend upon the
length of run and the allowable pressure loss estab
lished by the utility.

The gas connections to the unit are made at the
1/2 inch combination regulator-shut offs at each of
the two generators. The gas supply pipes enter the

unit through openings located at lower left rear and
lower right rear of unit. Install 1/2 inch ground
joint unions and 1/2 x 3/4 inch ells adjacent to
each combination regulator-shut off using two 1/2
inch X close nipples. The gas supply pipe from the
meter should terminate at the rear of the unit with a
tee. Install 3/4 inch pipe from this tee through the
openings in the rear casing to the 1/2 x 3/4 inch
ells adjacent to the regulator-shut offs at each
generator.

A. wrench-type shut-off valve should be installed in
the gas supply line within sight of, and convenient
to, the 451. It is recommended that ground joint
unions be installed in the gas supply piping just
outside the unit.

Joint compound (pipe dope) which is resistant to

the action of liquefied petroleum gases should be
applied sparingly and only to the male threads of

the joints.
After gas pipe connections have been made, purge

the lines and check for leakage. Use a soap and
water solution or other such material. Turn off
power supply to unit when purging the lines to
prevent glow coils in reignition pilots from being
energized. Never use matches, candles, flame or
other source of ignition to check leakage.

PILOT

The natural gas unit is equipped with two reignition
type pilots (one pilot in each generator). The pilots
will light automatically when supplied with gas and

are electrically energized. The circuit is arranged
to light the pilots sequentially. Several minutes
must be allowed for the first pilot to ignite and
make contact before second pilot will be energized.

To manually light the pilots use the procedure out
lined on the Lighting Instruction Plate attached to
generators. The pilot flame should be soft blue in
color. The flame should be of sufficient length to
provide good impingement on the unimetal element

of the Bryant pilot. Flame should extend upward
between the carry-over ports of the two adjacent
burners.

If the pilot flame does not have the appearance
described above, it may be adjusted by means of
the manual pilot shut-off valve which is equipped
with an adjustable screw. Turn the handle to the
full-open position and remove the screw cap on the
valve handle, thus exposing the adjustable screw.
Turn adjusting screw until flame has the desired
appearance. Replace screw cap.

V. CHARGING THE SYSTEM WITH WATER

Caution: Do not run the pump dry. Freezing con

ditions will not damage the pump; however, do not
attempt to operate the pump when chiller or chilled
water lines are frozen.

1. Turn off main manual gas shut-off valve.

2. Remove the filler caps located on top of both

chiller tanks.

3. Disconnect water line at chiller inlet. (When

installing the chilled water lines, it is advisable to
leave this connection open until lines have been
flushed.)

4. Fill tanks with tap water through the filler
opening of one tank until the distributor pans are
covered with water. A garden hose is useful for this
filling operation.

5. Start pump. Continue to supply water to the tank
and operate pump until all foreign matter has beeii
flushed from the lines. Then remove hose.

Note: If water does not circulate when the pump

is started, air may be trapped in the pump. Bleed
the air from pump through the 1/8 inch slotted head

108/451

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