Lennox HS27 Installation Instructions PDF

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Summary of Content for Lennox HS27 Installation Instructions PDF

Page 1 504,669M

02/04

2000 Lennox Industries Inc.

Dallas, Texas, USA

HS27 Outdoor Unit

HS27 outdoor units are designed for expansion valve sys-

tems only. They are not designed for RFC systems. Refer to

Lennox engineering handbook for expansion valve kits

which must be ordered separately.

Shipping & Packing List

1 Assembled HS27 outdoor unit

2 Grommets (for liquid and vapor lines)

1 Bushing (for low voltage wiring)

Check equipment for shipping damage. If you find any

damage, immediately contact the last carrier.

WARNING Improper installation, adjustment, alteration, service or maintenance can cause property damage, person- al injury or loss of life. Installation and service must be performed by a qualified installer or service agency.

IMPORTANT The Clean Air Act of 1990 bans the intentional vent- ing of refrigerant (CFCs and HCFCs) as of July 1, 1992. Approved methods of recovery, recycling or reclaiming must be followed. Fines and/or incarcera- tion may be levied for noncompliance.

INSTALLATION INSTRUCTIONS

HS27 SERIES UNITS CONDENSING UNITS 504,669M 02/04

Supersedes 12/02

Table of Contents

HS27 Outdoor Unit 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Shipping & Packing List 1. . . . . . . . . . . . . . . . . . . . . . . . . General Information 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Unit Dimensions 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Parts Arrangement 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Setting the Unit 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electrical 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Refrigerant Piping 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Refrigerant Metering Device 9. . . . . . . . . . . . . . . . . . . . . Manifold Gauge Set 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Service Valves 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Leak Testing 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Evacuation 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . StartUp 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Charging 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . System Operation 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Maintenance 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Optional Accessories 14. . . . . . . . . . . . . . . . . . . . . . . . . . Startup & Performance Check List 15. . . . . . . . . . . . . . .

RETAIN THESE INSTRUCTIONS FOR FUTURE REFERENCE

General Information

These instructions are intended as a general guide and do

not supersede local codes in any way. Consult authorities

having jurisdiction before installation.

WARNING This product and/or the indoor unit it is matched with may contain fiberglass wool.

Disturbing the insulation during installation, mainte- nance, or repair will expose you to fiberglass wool dust. Breathing this may cause lung cancer. (Fiber- glass wool is known to the State of California to cause cancer.)

Fiberglass wool may also cause respiratory, skin, and eye irritation.

To reduce exposure to this substance or for further information, consult material safety data sheets available from address shown below, or contact your supervisor.

Lennox Industries Inc.

P.O. Box 799900 Dallas, TX 753799900

Litho U.S.A.

Page 2

Unit Dimensions inches (mm)

electrical inlets

vapor line inlet

liquid line inlet

DISCHARGE AIR

inlet

air

COMPRESSOR

B

Top View

Side ViewAccess View

4-1/2 (114)

2-3/4 (70) 4

(102) 6-1/16 (154)

1-3/8 (35)

A

4-7/8 (22) 4

(102)

2-9/16 (65)

18-5/8 (473)

26-5/8 (676)

34-1/16 (865)

2 (51)

28-1/8 (714)

7-1/2 (191)

7-1/2 (191)3-7/8

(98) 3-7/8 (98)

airinlet

airinlet

2 (51)

32-1/8 (816)

Model No. A B

HS27-024 in. 30-7/8 12-3/4

HS27-030 mm 784 324

HS27-036 in. 40-7/8 19-3/4

HS27-042 mm 1038 502

Page 3

Parts Arrangement

Figure 1

outdoor fan (not shown)

top of cabinet

contactor

run capacitor

terminal box

liquid line service valve

and gauge port

vapor valve and gauge port

compressor

low pressure switch

high pressure switch

ground lug

Setting the Unit

CAUTION In order to avoid injury, take proper precaution when lifting heavy objects.

CAUTION Danger of sharp metallic edges. Can cause injury. Take care when servicing unit to avoid accidental contact with sharp edges.

Refer to unit dimensions for sizing mounting slab, platform-

s, or supports. Refer to figure 2 for installation clearances.

36" (914 mm)

36" (914 mm)

*36" (914 mm)

*36" (914 mm)

Installation Clearances

Figure 2

NOTE A service access clearance of 30" (762 mm) must be maintained in front of the service access panel. Clearance to one side must be 36" (914 mm). Clearance to one of the remaining two sides may be 12" (304 mm) and the final side may be 6" (152 mm).

NOTE A clearance of 24" (610 mm) must be maintained between two units.

NOTE 48" (1219 mm) clearance required on top of unit. Maximum soffit overhang is 36" (914 mm).

Page 4

A Slab Mounting

When you install the unit at grade level, the top of the slab

should be high enough above the grade so that water from

higher ground will not collect around the unit. See figure 3.

Slab should have a slope tolerance away from the building

of 2 degrees or 2 inches per 5 feet (51 mm per 1.5 m).

2 degrees or 2 in. per 5 foot

(51 mm per 1.5 m) slope tolerance away from building structure

Slab Mounting

ground level

mounting slab

building structure

discharge air

Figure 3

B Roof Mounting

Install unit at a minimum of 4 inches above surface of the roof.

Care must be taken to ensure weight of unit is properly distrib-

uted over roof joists and rafters. Either redwood or steel sup-

ports are recommended.

Electrical

In the U.S.A., wiring must conform with current local codes

and the current National Electric Code (NEC). In Canada,

wiring must conform with current local codes and the current

Canadian Electrical Code (CEC).

Refer to the furnace or blower coil installation instructions

for additional wiring application diagrams and refer to unit

nameplate for minimum circuit ampacity and maximum

overcurrent protection size.

WARNING Unit must be grounded in accordance with national and local codes. Electric Shock Hazard. Can cause injury or death.

1. Install line voltage power supply to unit from a properly

sized disconnect switch.

2. Ground unit at unit disconnect switch or to an earth

ground.

NOTE To facilitate conduit, a hole is in the bottom of

the control box. Connect conduit to the control box us

ing a proper conduit fitting.

NOTE Units are approved for use only with copper

conductors.

24V, Class II circuit connections are made in the low

voltage junction box. Refer to figure 4 for field wiring

diagram.

NOTE A complete unit wiring diagram is located in

side the unit control box cover.

3. Install room thermostat (ordered separately) on an in-

side wall approximately in the center of the conditioned

area and 5 feet (1.5 m) from the floor. It should not be

installed on an outside wall or where it can be effected

by sunlight, drafts or vibrations.

4. Install low voltage wiring from outdoor to indoor unit

and from thermostat to indoor unit. See figure 5.

Page 5

Outdoor Unit Field Wiring Diagram

YELLOW

(LEADLESS)

Figure 4

Thermostat Designations

R

W1

Y

G

C

R

W

Y

G

C

Thermostat Furnace

Outdoor Unit

Y1 Outdoor Unit

C Outdoor Unit

power

heat

cooling

indoor blower

common

NOTE see unit wiring diagram for power supply connections.

NOTE If the indoor unit is not equipped with blower relay, it must be fieldprovided and installed (P83251 or equivalent).

Figure 5

Page 6

Refrigerant Piping

Field refrigerant piping consists of liquid and vapor lines

from the outdoor unit (sweat connections) to the indoor coil

(flare or sweat connections). Use Lennox L15 (sweat, non-

flare) series line sets as shown in table 1 or use field-fabri-

cated refrigerant lines. Refer to Refrigerant Piping Guide

(Corp. 9351L9) for proper size, type, and application of

fieldfabricated lines. Valve sizes are also listed in table 1.

Table 1 Refrigerant Line Sets

HS27

Field Valve Size Connections

Recommended Line Set

Liquid Line

Vapor Line

Liquid Line

Vapor Line

L15 Line Sets

024 030

3/8 in (10 mm)

3/4 in. (19 mm)

3/8 in (10 mm)

3/4 in. (19 mm)

L1541 15 ft. 50 ft.

(4.6 m 15 m)

036 042

3/8 in (10 mm)

7/8 in. (22 mm)

3/8 in (10 mm)

7/8 in. (22 mm)

L1565 15 ft. 50 ft.

(4.6 m 15 m)

NOTE Units are designed for line sets of up to 50 feet (15

m). For applications longer than 50 feet, consult the Len-

nox Refrigerant Piping Guide (Corp. 9351L9). Select line

set diameters from table 1 to ensure that oil returns to the

compressor.

Installing Refrigerant Line

During the installation of any heat pump or a/c system, it is

important to properly isolate the refrigerant lines to prevent

unnecessary vibration. Line set contact with the structure

(wall, ceiling or floor) causes some objectionable noise

when vibration is translated into sound. As a result, more

energy or vibration can be expected. Closer attention to

line set isolation must be observed.

Following are some points to consider when placing and

installing a highefficiency outdoor unit:

1- Placement Be aware some localities are adopting

sound ordinances based on how noisy the unit is from

the adjacent property not at the original installation.

Install the unit as far as possible from the property line.

When possible, do not install the unit directly outside a

window. Glass has a very high level of sound transmis-

sion.

2- Line Set Isolation The following illustrations demon-

strate procedures which ensure proper refrigerant line

set isolation. Figure 6 shows how to install line sets on

vertical runs. Figure 7 shows how to install line sets on

horizontal runs. Figure 8 shows how to make a transition

from horizontal to vertical. Finally, figure 9 shows how to

place the outdoor unit and line set.

Page 7

Refrigerant Line Sets How To Install Vertical Runs

(new construction shown)

PVC Pipe Fiberglass Insulation

Caulk

Outside Wall

Vapor Line (wrapped with Armaflex)

Liquid Line

IMPORTANT - Refrigerant lines must not contact

structure.

Outside Wall

Inside Wall

Liquid LineVapor Line IMPORTANT - Refrigerant lines must not contact wall.

Wood Block Between Studs

Strap

Sleeve

Wood Block

Strap

Sleeve

Wire Tie

Wire Tie

Wire Tie

NOTE - Similar installation practices should be used if line set is to be installed on exterior of outside wall.

Figure 6

Page 8

Refrigerant Line Sets: Installing Horizontal Runs

8 feet

8 feet

Metal Sleeve

Strapping Material (around vapor line only)

Tape or Wire Tie

Wire Tie (around vapor line only)

Floor Joist or Roof Rafter

Tape or Wire Tie

Strap the vapor line to the joist or rafter at 8 ft. intervals then strap the liquid line to the vapor line.

To hang line set from joist or rafter, use either metal strapping material or anchored heavy nylon wire ties.

Floor Joist or Roof Rafter

Figure 7

Page 9

Refrigerant Line Sets: Transition From Vertical To Horizontal

Liquid Line

Vapor Line Wrapped in

Armaflex

Strap Liquid Line To Vapor Line

Metal Sleeve

Anchored Heavy Nylon Wire Tie

Automotive Muffler-Type

Hanger

Wall Stud

Wall Stud

Liquid Line

Vapor Line Wrapped in

Armaflex

Strap Liquid Line To Vapor Line

Metal Sleeve

Figure 8

Outside Unit Placement and Installation

Install unit away from windows.

Two 90 elbows installed in line set will reduce line set vibration.

Figure 9

Page 10

Brazing Connection Procedure

1 Cut ends of the refrigerant lines square (free from nicks

or dents). Debur the ends. The pipe must remain

round, do not pinch end of the line.

2 Before making line set connections, use dry nitrogen to

purge the refrigerant piping. This will help to prevent

oxidation and the introduction of moisture into the sys-

tem.

3 Use silver alloy brazing rods (5 or 6 percent minimum

silver alloy for coppertocopper brazing or 45 percent

silver alloy for coppertobrass or coppertosteel braz-

ing) which are rated for use with HCFC22 refrigerant.

Wrap a wet cloth around the valve body and the copper

tube stub. Braze the line set to the service valve.

4 Wrap a wet cloth around the valve body and copper

tube stub to protect it from heat damage during braz-

ing. Wrap another wet cloth underneath the valve body

to protect the base paint.

NOTE The tube end must stay bottomed in the fitting

during final assembly to ensure proper seating, sealing

and rigidity.

5 Install a fieldprovided thermal expansion valve (ap-

proved for use with HCFC22 refrigerant) in the liquid

line at the indoor coil.

Refrigerant Metering Device

H27 units are used in expansion valve systems only. See

the Lennox Engineering Handbook for approved TXV

match-ups and application information.

Expansion valves equipped with Chatleff fittings are avail-

able from Lennox. Refer to the Engineering Handbook for

applicable expansion valves for use with specific match-

ups.

If you install an expansion valve with an indoor coil that

includes a fixed orifice, remove the orifice before instal-

ling the expansion valve.

IMPORTANT Failure to remove RFC orifice when installing an ex- pansion valve on the indoor coil will result in improp- er operation and damage to the system.

See figure 10 for installation of the check expansion valve.

Metering Device Installation

expansion valve

oring

oring

strainer

liquid line stub

distributor

Figure 10

Manifold Gauge Set

When checking the unit charge, use a manifold gauge set that is equipped with low loss" hoses. Do not use a man- ifold gauge set with anything other than a low loss" hose.

Service Valves

The liquid line and vapor line service valves (figures 11 and 12) and gauge ports are used for leak testing, evacuating, charging and checking charge. See table 2 for torque re- quirements.

Each valve is equipped with a service port which has a fac- toryinstalled Schrader valve. A service port cap protects the Schrader valve from contamination and serves as the primary leak seal.

Table 2 Torque Requirements

Part Recommended Torque

Service valve cap 8 ft. lb. 11 NM

Sheet metal screws 16 in. lb. 2 NM

Machine screws #10 28 in. lb. 3 NM

Compressor bolts 90 in. lb. 10 NM

Gauge port seal cap 8 ft. lb. 11 NM

To Access Schrader Port:

1 Remove the service port cap with an adjustable wrench.

2 Connect gauge to the service port.

3 When testing is complete, replace the service port cap. Tighten finger tight, then an additional 1/6 turn.

To Open Service Valve:

1 Remove stem cap with an adjustable wrench.

2 Use a service wrench with a hexhead extension to back the stem out counterclockwise as far as it will go.

Page 11

NOTE Use a 3/16" hex head extension for liquid line

sizes or a 5/16" extension for vapor line sizes.

3 Replace the stem cap. Tighten finger tight, then tighten

an additional 1/6 turn.

To Close Service Valve:

1 Remove stem cap with an adjustable wrench.

2 Use a service wrench with a hexhead extension to turn

the stem clockwise to seat the valve. Tighten firmly.

NOTE Use a 3/16" hex head extension for liquid line

sizes or a 5/16" extension for vapor line sizes.

3 Replace the stem cap. Tighten finger tight, then tighten

an additional 1/6 turn.

Vapor Line (Ball Type) Service Valve

Vapor line service valves function the same way as the oth-

er valves, the difference is in the construction. These

valves are not rebuildable. If a valve has failed, you must

replace it. A ball valve is illustrated in figure 12.

The ball valve is equipped with a service port with a factory

installed Schrader valve. A service port cap protects the

Schrader valve from contamination and assures a leak

free seal.

Service Valve (Valve Closed)

Schrader valve open to line set when valve is

closed (front seated)

service port

service port cap

stem cap

insert hex wrench here

(valve front seated)

to outdoor coil

to indoor coil

Service Valve (Valve Open)

Schrader valve

service port

service port cap

insert hex wrench here

to indoor coil

to outdoor coil

stem cap

Figure 11

Vapor Line (Ball Type) Service Valve (Valve Open)

Schrader valve

stem cap

To open: rotate stem counter-clockwise 90. To close: use adjustable wrench and

rotate stem clockwise 90.

ball (shown open)

service port cap

service port

field side

unit side

stem

Figure 12

Leak Testing

After the line set has been connected to the indoor and

outdoor units, the line set connections and indoor unit

must be checked for leaks.

WARNING Danger of fire. Bleeding the refrigerant charge from only the high side may result in the low side shell and suc- tion tubing being pressurized. App- plication of a brazing torch while pres- surized may result in ignition of the refrigerant and oil mixture check the high and low pressures before unbra- zing.

WARNING Refrigerant can be harmful if it is inhaled. Refrigerant must be used and recovered responsibly.

Failure to follow this warning may result in person- al injury or death.

WARNING Danger of explosion: Can cause equipment damage, injury or death. Never use oxygen to pressurize a re- frigeration or air conditioning system. Oxygen will explode on contact with oil and could cause personal injury.

Page 12

WARNING Danger of explosion: Can cause equipment damage, injury or death. When using a high pressure gas such as dry nitrogen to pressurize a refrigeration or air conditioning system, use a regulator that can control the pressure down to 1 or 2 psig (6.9 to 13.8 kPa).

Using an Electronic Leak Detector or Halide

1 Connect a cylinder of HCFC-22 to the center port of the

manifold gauge set.

2 With both manifold valves closed, open the valve on

the HCFC-22 cylinder (vapor only).

3 Open the high pressure side of the manifold to allow

the HCFC-22 into the line set and indoor unit. Weigh in

a trace amount of HCFC-22. [A trace amount is a maxi-

mum of 2 ounces (57 g) or 3 pounds (31 kPa) pres-

sure.] Close the valve on the HCFC-22 cylinder and the

valve on the high pressure side of the manifold gauge

set. Disconnect the HCFC-22 cylinder.

4 Connect a cylinder of nitrogen with a pressure regulat-

ing valve to the center port of the manifold gauge set.

5 Connect the manifold gauge set high pressure hose to

the vapor valve service port. (Normally, the high pres-

sure hose is connected to the liquid line port; however,

connecting it to the vapor port better protects the man-

ifold gauge set from high pressure damage.)

6 Adjust the nitrogen pressure to 150 psig (1034 kPa).

Open the valve on the high side of the manifold gauge

set which will pressurize line set and indoor unit.

7 After a few minutes, open a refrigerant port to ensure

the refrigerant you added is adequate to be detected.

(Amounts of refrigerant will vary with line lengths.)

Check all joints for leaks. Purge nitrogen and HCFC-22

mixture. Correct any leaks and recheck.

Evacuation

Evacuating the system of noncondensables is critical for

proper operation of the unit. Noncondensables are defined

as any gas that will not condense under temperatures and

pressures present during operation of an air conditioning

system. Noncondensables and water vapor combine with

refrigerant to produce substances that corrode copper pip-

ing and compressor parts.

IMPORTANT Use a thermocouple or thermistor electronic vacuum gauge that is calibrated in microns. Use an instrument that reads from 50 microns to at least 10,000 microns.

1 Connect manifold gauge set to the service valve ports

as follows:

low pressure gauge to vapor line service valve

high pressure gauge to liquid line service valve

2 Connect micron gauge.

3 Connect the vacuum pump (with vacuum gauge) to the

center port of the manifold gauge set.

4 Open both manifold valves and start the vacuum

pump.

5 Evacuate the line set and indoor unit to an absolute

pressure of 23,000 microns (29.01 inches of mercu-

ry). During the early stages of evacuation, it is desir-

able to close the manifold gauge valve at least once to

determine if there is a rapid rise in absolute pressure.

A rapid rise in pressure indicates a relatively large leak.

If this occurs, repeat the leak testing procedure.

NOTE The term absolute pressure means the total

actual pressure within a given volume or system,

above the absolute zero of pressure. Absolute pres-

sure in a vacuum is equal to atmospheric pressure mi-

nus vacuum pressure.

6 When the absolute pressure reaches 23,000 microns

(29.01 inches of mercury), close the manifold gauge

valves, turn off the vacuum pump and disconnect the

manifold gauge center port hose from vacuum pump.

Attach the manifold center port hose to a nitrogen cylin-

der with pressure regulator set to 150 psig (1034 kPa)

and purge the hose. Open the manifold gauge valves

to break the vacuum in the line set and indoor unit.

Close the manifold gauge valves.

CAUTION Danger of Equipment Damage. Avoid deep vacuum operation. Do not use compres- sors to evacuate a system. Extremely low vacuums can cause internal arcing and compressor failure. Damage caused by deep vacuum operation will void warranty.

7 Shut off the nitrogen cylinder and remove the manifold

gauge hose from the cylinder. Open the manifold

gauge valves to release the nitrogen from the line set

and indoor unit.

8 Reconnect the manifold gauge to the vacuum pump,

turn the pump on, and continue to evacuate the line set

and indoor unit until the absolute pressure does not

rise above 500 microns (29.9 inches of mercury) within

a 20minute period after shutting off the vacuum pump

and closing the manifold gauge valves.

9 When the absolute pressure requirement above has

been met, disconnect the manifold hose from the vacu-

um pump and connect it to an upright cylinder of

HCFC-22 refrigerant. Open the manifold gauge valves

to break the vacuum from 1 to 2 psig positive pressure in

the line set and indoor unit. Close manifold gauge

valves and shut off the HCFC-22 cylinder and remove

the manifold gauge set.

Page 13

StartUp

1 Rotate the fan to check for frozen bearings or binding.

2 Inspect all factory and field-installed wiring for loose

connections.

3 After evacuation is complete, open the liquid line and

vapor line service valves to release the refrigerant

charge (contained in outdoor unit) into the system.

4 Replace the stem caps and secure finger tight, then

tighten an additional one-sixth (1/6) of a turn.

5 Check voltage supply at the disconnect switch. The

voltage must be within the range listed on the units

nameplate. If not, do not start the equipment until you

have consulted the power company and the voltage

condition has been corrected.

6 Set the thermostat for a cooling demand. Turn on pow-

er to the indoor blower and close the outdoor unit dis-

connect switch to start the unit.

7 Recheck voltage while the unit is running. Power must

be within range shown on the nameplate.

Charging

Units are factory charged with the amount of HCFC-22 re-

frigerant indicated on the unit nameplate. This charge is

based on a matching indoor coil and outdoor coil with a 15

ft. (4.6 m) line set. For varying lengths of line set, refer to

table 3 for refrigerant charge adjustment check.

Table 3

Liquid Line Set Diameter

Oz. per 5 ft. (g per 1.5 m) adjust from 15 ft. (4.6 m) line set*

3/8 in. (9.5 mm) 3 ounces per 5 ft. (88.05 g per 1.5 m)

*If line length is greater than 15 ft. (4.6 m), add this amount. If line length is less than 15 ft. (4.6 m), subtract this amount

The outdoor unit should be charged during warm weather.

However, applications arise in which charging must occur

in the colder months. The method of charging is deter-

mined by the units refrigerant metering device and the

outdoor ambient temperature.

Measure the liquid line temperature and the outdoor ambi-

ent temperature as outlined below. Close manifold gauge

set valves.

1 Connect the manifold gauge set to the service valves:

low pressure gauge to vapor valve service port

high pressure gauge to liquid valve service port

Connect the center manifold hose to an upright cylin-

der of HCFC22.

2 Set the room thermostat to call for heat. This will create

the necessary load for properly charging the system in

the cooling cycle.

3 Use a digital thermometer to record the outdoor ambi-

ent temperature.

4 When the heating demand has been satisfied, switch

the thermostat to cooling mode with a set point of 68F

(20C). When pressures have stabilized, use a digital

thermometer to record the liquid line temperature.

5 The outdoor temperature will determine which charg-

ing method to use. Proceed with the appropriate charg-

ing procedure.

Weighing in the Charge TXV Systems Outdoor

Temp < 65F (18C)

If the system is void of refrigerant, or if the outdoor ambient

temperature is cool, the refrigerant charge should be

weighed into the unit. Do this after any leaks have been re-

paired.

1 Recover the refrigerant from the unit.

2 Conduct a leak check, then evacuate as previously

outlined.

3 Weigh in the unit nameplate charge.

If weighing facilities are not available or if you are charging

the unit during warm weather, follow one of the other proce-

dures outlined below.

Page 14

Charging Using Normal Operating Pressures

and the Approach Method

TXV Systems Outdoor Temp. > 65F (18C)

The following procedure is intended as a general guide and

is for use on expansion valve systems only. For best results,

indoor temperature should be 70F (21C) to 80F (26C).

Monitor system pressures while charging.

1 Record outdoor ambient temperature using a digital

thermometer.

2 Attach high pressure gauge set and operate unit for

several minutes to allow system pressures to stabilize.

3 Compare stabilized pressures with those provided in

table 5, Normal Operating Pressures." Minor varia-

tions in these pressures may be expected due to differ-

ences in installations. Significant differences could

mean that the system is not properly charged or that a

problem exists with some component in the system.

Pressures higher than those listed indicate that the

system is overcharged. Pressures lower than those

listed indicate that the system is undercharged. Verify

adjusted charge using the approach method.

Approach Method

4 Use the same digital thermometer you used to check

the outdoor ambient temperature to check the liquid

line temperature.

5 The difference between the ambient and liquid temper-

atures should match values given in table 4. If the val-

ues dont agree with the those in table 4, add refriger-

ant to lower the approach temperature, or recover re-

frigerant from the system to increase the approach

temperature.

Table 4

Approach Values

Model Number Liquid Temp. Minus Ambient

Temp. F (C)

HS27024 5 + 1 ( 3 + .5)

HS27030 5 + 1 ( 3 + .5)

HS27036 6 + 1 ( 3.3 + .5)

HS27042 7 + 1 ( 3.9 + .5)

NOTE For best results, the same digital thermometer should be used to check both outdoor ambient and liquid temperatures.

IMPORTANT Use table 5 to perform maintenance checks. Table 5 is not a procedure for charging the system. Minor variations in these pressures may be due to differ- ences in installations. Significant deviations could mean that the system is not properly charged or that a problem exists with some component in the system. See table 5.

Table 5

Normal Operating Pressures

Outdoor HS27024 HS27030 HS27036 HS27042

Temp. (F) Liq. + 10 psig

Suct. + 5 psig

Liq. + 10 psig

Suct. + 5 psig

Liq. + 10 psig

Suct. + 5 psig

Liq. + 10 psig

Suct. + 5 psig

65 135 78 139 79 136 76 141 82

75 159 79 163 80 160 77 166 82

85 186 80 180 81 188 80 185 82

95 216 82 219 83 217 80 226 85

105 249 83 252 84 251 82 257 85

Page 15

System Operation

The outdoor unit and indoor blower cycle on demand from the room thermostat. When the thermostat blower switch is in the ON position, the indoor blower operates continuously.

CAUTION Danger of equipment damage. Do not bypass the dis- charge thermostat.

High Pressure Switch

HS27 units are equipped with a high pressure switch that is located in the discharge line of the compressor. The switch (SPST, manual reset, normally closed) removes power from the compressor when discharge pressure rises above factory setting at 410 + 10 psi.

Low Pressure Switch

HS27 units are also equipped with a low pressure switch that is located in the vapor line of the compressor. The switch (SPST, autoreset, normally closed) removes power from the compressor when vapor line pressure drops be- low factory setting at 25 + 5 psi.

Maintenance

WARNING Electric shock hazard. Can cause inju- ry or death. Before attempting to per- form any service or maintenance, turn the electrical power to unit OFF at dis- connect switch(es). Unit may have multiple power supplies.

Maintenance and service must be performed by a qualified

installer or service agency. At the beginning of each cooling

season, the system should be checked as follows:

1 Clean and inspect the outdoor coil. The coil may be flushed with a water hose. Ensure the power is turned off before you clean the coil.

2 The outdoor fan motor is prelubricated and sealed. No further lubrication is needed.

3 Visually inspect connecting lines and coils for evidence of oil leaks.

4 Check wiring for loose connections.

5 Check for correct voltage at unit (unit operating).

6 Check ampdraw outdoor fan motor. Unit nameplate _________ Actual ____________ .

NOTE If the owner complains of insufficient cooling, the unit should be gauged and refrigerant charge checked. Refer to section on refrigerant charging in this instruction.

Indoor Coil

1 Clean coil, if necessary.

2 Check connecting lines and coils for evidence of oil leaks.

3 Check the condensate line and clean it if necessary.

Indoor Unit

1 Clean or change filters.

2 Adjust blower speed for cooling. Measure the pressure drop over the coil to determine the correct blower CFM. Refer to the unit information service manual for pressure drop tables and procedure.

3 Belt Drive Blowers Check belt for wear and proper tension.

4 Check all wiring for loose connections

5 Check for correct voltage at unit (blower operating).

6 Check ampdraw on blower motor

Unit nameplate_________ Actual ____________.

Optional Accessories

The following optional accessories are available for use

with outdoor units:

Loss of Charge Kit

High Pressure Switch Kit

Compressor Monitor

Compressor Crankcase Heater

Hail Guards

Mounting Bases

Timed Off Control

Standoff Kit

Sound Cover

Low Ambient Kit

Page 16

Startup & Performance Check List

Startup and Performance Check List

Job Name

Job Location

Installer

Unit Model No.

Nameplate Voltage

Rated Load Ampacity

Maximum Fuse or Circuit Breaker

Refrigerant Lines:

Service Valves Fully Opened?

Outdoor Fan Checked?

Job No.

City

City

Serial No.

Date

State

State

Service Technician

Compressor Outdoor Fan

Indoor Filter Clean?Electrical Connections Tight? Supply Voltage (Unit Off)

Vapor Pressure

Thermostat

Refrigerant Charge Checked?

Calibrated? Properly Set? Level?

Prope

Manualsnet FAQs

If you want to find out how the HS27 Lennox works, you can view and download the Lennox HS27 Installation Instructions on the Manualsnet website.

Yes, we have the Installation Instructions for Lennox HS27 as well as other Lennox manuals. All you need to do is to use our search bar and find the user manual that you are looking for.

The Installation Instructions should include all the details that are needed to use a Lennox HS27. Full manuals and user guide PDFs can be downloaded from Manualsnet.com.

The best way to navigate the Lennox HS27 Installation Instructions is by checking the Table of Contents at the top of the page where available. This allows you to navigate a manual by jumping to the section you are looking for.

This Lennox HS27 Installation Instructions consists of sections like Table of Contents, to name a few. For easier navigation, use the Table of Contents in the upper left corner.

You can download Lennox HS27 Installation Instructions free of charge simply by clicking the “download” button in the upper right corner of any manuals page. This feature allows you to download any manual in a couple of seconds and is generally in PDF format. You can also save a manual for later by adding it to your saved documents in the user profile.

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