York E2FB120 User Manual

Page 8

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(29 feet x 8.0 psi/100 feet) .............................................2.3 psi

7 feet of 1-3/8" OD, type “L” copper tubing (horizontal)

(7 feet x 2.8 psi/100 feet) ...............................................0.2 psi

Fitting*....................................................................................0.5 psi

Vapor Line Pressure Drop = 3.0 psi

*

Determine the pressure drop of the fittings for each installation - DO NOT use the estimated

values as shown in the above examples.

Although longer vapor lines are permissible, friction losses ex-

ceeding3 psi (2°F) will reduce system capacity in both the cool-

ing and heating cycles.

SERVICE VALVES

These outdoor units have both vapor and liquid line service

valves.

Both valves are shipped from the factory front-seated and

closedwith the valve stem in the maximumclockwiseposition.

These servicevalves are the back-seatingtype and have a 1/4"

male flare accessport for evacuatingand chargingthe system.

Shrader access valves are provided on the compressor vapor

and discharge lines for pressure checking the system.

All access ports are sealed with a removable cap. Never re-

move a cap unless the valve is fully back-seated with its valve

stem in the maximum counter-clockwise position because the

refrigerant charge will be lost.

EXTENDING THE SERVICE PORTS

Refer to Fig.6:
1. Loosen the screws securing the service ports in shipping

position. (See FIG 6).

2. Push the service ports through the corner post.

3. Tighten the screws to secure the service ports for installation.

INSTALLATION

Since the condensing units are shipped with a holding charge

of Refrigerant-22, they can be checked for a refrigerant leak by

depressing the stem on either of the service ports that extend

through the cabinet. As soon as some internal pressure is re-

lieved release the stem. DO NOT release the entire holding

charge.

If the unit has already lost its holding charge, it should be leak

tested and the necessary repairs should be made. If the unit

has maintained its holding charge, you can assume that it has

no leaks and proceed with the installation.

CAUTION: When making a braze connection, wrap a wet rag

around all tubing inside the unit to prevent damage

to the other components.

Dry nitrogen should always be supplied through a

connection while it is being brazed or unbrazed

because the temperature required to make or

break a brazed joint is sufficiently high to cause

oxidation of the copper unless an inert atmos-

phere is provided. The flow of nitrogen should be

continued until the joint has cooled.

WARNING: The dry nitrogen must always be supplied through

a pressure regulating valve.

Before installing the liquid line between the outdoor and indoor

units, remove the copper disc from the liquid connectionon the

outdoor unit per the following procedure:

1. Make sure the refrigerant in the line has been recovered

and that the liquid service valve on the unit is front-seated

and closed. The valve stem should be turned to its maxi-

mum clockwise position.

2. Drill a small hole through the disc before unbrazing it to per-

mit a flow of dry nitrogen through the connection while it is

being unbrazed.

WARNING: This hole is also required to prevent the internal

pressure from building up as the disc is being un-

brazed and from blowing the disc off.

This warning applies to any disc being removed

from a service valve, coil connection, etc.

3. Remove the cap from the 1/4" access port on the liquid line stop

valve.

4. Connect a supply of dry nitrogen to this access port.

5. Unbraze the copper disc from the liquid connection while

maintaining a minimum flow of dry nitrogen through the

connection.

After the disc has been removed,

1. Burnish the external surfaces of the liquid connection on

the outdoor unit and the end of the field-supplied piping be-

ing used for the liquid line.

NOTE: Clean surfaces are essential for a well brazed connec-

tion.

2. Carefully clean the internal surfaces of the above. Any par-

ticles left on these surfaces may lead to a future system

malfunction.

8

Unitary Products Group

035-15410-002-B-0404

System

Model

Refrigerant

Flow Rate,

4

(Lbs/Min)

Type “L”

Copper Tubing

(In. OD)

Friction

Loss,

5,6

(PSI/100 Ft.)

EFB090/FEH090

22.5

1-1/8

4.7

1-3/8

1.6

EFB120/FEH120

30.0

1-1/8

8.0

1-3/8

2.8

1

All horizontal vapor lines should be level since the refrigerant flows in both directions.

2

All vapor lines with a vertical rise exceeding 50 feet should have an intermediate trap. Small

radius traps will provide drainage points for the oil which is in the riser when the circuit is

deactivated. When the circuit is reactivated, the oil will be returned to the compressor more

quickly and in smaller slugs.

3

Every vapor riser greater than 5 feet in height should have a small radius trap at the bottom.

4

Based on Refrigerant-22 at the nominal cooling capacity of the system, a vapor temperature

of 40°F and a liquid temperature of 105°F. Since refrigerant flow rates will be a little lower at

the nominal heating capacity of each system, vapor line friction loss should always be based

on cooling operation.

5

Although vapor lines should be sized for a friction loss equivalent to a 2°F change in saturation

temperature (or approximately 3 psi), sizing the lines for the proper return of oil is more

important.

6

These friction losses do not include any allowance for fittings. Only use a 1-1/8" riser when

the indoor unit is above the outdoor unit.

TABLE 5

- VAPOR LINES

1,2,3

Refrigerant

Line

2

Line Size,

OD (In.)

Refrigerant Charge

(Lb/Ft)

Liquid

5/8

0.113

Vapor

1-1/8

0.013

1-3/8

1

Charges are based on 40°F suction temperature and 105°F liquid temperature.

2

Type “L” copper tubing.

TABLE 6

- REFRIGERANT LINE CHARGE

1

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