Unitary products group YMB Series, HC3A Series, HL3A Series Installation Manual

INSTALLATION MANUAL

R-22
OUTDOOR SPLIT-SYSTEM
HEAT PUMP

MODELS: 13 SEER - YMB / HC3A / HL3A SERIES

1.5 TO 5 TONS

TABLE OF CONTENTS

GENERAL 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

UNIT INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

INSTALLATIONS REQUIRING TXV . . . . . . . . . . . . . . . . . . . . . . . . . . 5

ELECTRICAL CONNECTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

LIST OF FIGURES

Typical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Oil Trap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Tubing Hanger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Underground Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Heat Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

Typical Field Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

CFM Selection Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Heat Pump Flow Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

LIST OF TABLES

R-22 Saturated Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

TEST Input Functionality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Operational Mode Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Status Code Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

X/L Output Categories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

Operational Fault Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

Sensor or Switch Fault Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

Wiring Related Fault Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

Defrost Initiate Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

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LISTED

ISO 9001

Certified Quality

Management System

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Certification applies only

when the complete

system is listed

EVACUATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

SYSTEM CHARGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

SYSTEM OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

INSTRUCTING THE OWNER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18

WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20

Demand Defrost Control Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8

Defrost Operation Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

Hot Heat Pump Indoor Airflow Control . . . . . . . . . . . . . . . . . . . . . . . .14

Jumper Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20

Air Handler Auxiliary Heat Functionality . . . . . . . . . . . . . . . . . . . . . . 16

Fossil Fuel Furnace Auxiliary Heat Functionality . . . . . . . . . . . . . . . 16

1-1/2 Ton Subcooling Charging Chart . . . . . . . . . . . . . . . . . . . . . . . 18

2 Ton Subcooling Charging Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

2-1/2 Ton Subcooling Charging Chart . . . . . . . . . . . . . . . . . . . . . . . 18

3 Ton Subcooling Charging Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

3-1/2 Ton Subcooling Charging Chart . . . . . . . . . . . . . . . . . . . . . . . 19

4 Ton Subcooling Charging Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

5 Ton Subcooling Charging Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

SECTION I: GENERAL

The outdoor units are designed to be connected to a matching indoor
coil with sweat connect lines. Sweat connect units are factory charged
with refrigerant for a matching indoor coil plus 15 feet of field supplied
lines.

Matching indoor coils are available with a thermal expansion valve or
an orifice liquid feed sized for the most common usage. The orifice size
and/or refrigerant charge may need to be changed for some indoor-out­door unit combinations, elevation differences, or total line lengths. Refer
to Application Data covering “General Piping Recommendations and
Refrigerant Line Length” (Part Number 036-61920-001).

SECTION II: SAFETY

This is a safety alert symbol. When you see this symbol on
labels or in manuals, be alert to the potential for personal
injury.

Understand and pay particular attention to the signal words DANGER,

WARNING , or CAUTION.
DANGER indicates an imminently hazardous situation, which, if not

avoided, will result in death or serious injury

WARNING indicates a potentially hazardous situation, which, if not
avoided, could result in death or serious injury

.

CAUTION indicates a potentially hazardous situation, which, if not
avoided may result in minor or moderate injury

. It is also used to
alert against unsafe practices and hazards involving only property dam­age

Improper installation may create a condition where the operation of
the product could cause personal injury or property damage.

Improper installation, adjustment, alteration, service, or mainte­nance can cause injury or property damage. Refer to this manual
for assistance or for additional information, consult a qualified con­tractor, installer, or service agency.

This product must be installed in strict compliance with the
enclosed installation instructions and any applicable local, state,

.

and national codes including, but not limited to building, electrical,
and mechanical codes.

170761-UIM-B-0406

170761-UIM-B-0406

INSPECTION

As soon as a unit is received, it should be inspected for possible dam­age during transit. If damage is evident, the extent of the damage
should be noted on the carrier’s delivery receipt. A separate request for
inspection by the carrier’s agent should be made in writing. See Local
Distributor for more information.

LIMITATIONS

The unit should be installed in accordance with all National, State, and
Local Safety Codes and the limitations listed below:

1. Limitations for the indoor unit, coil, and appropriate accessories
must also be observed.

2. The outdoor unit must not be installed with any duct work in the air
stream. The outdoor fan is the propeller type and is not designed
to operate against any additional external static pressure.

3. The maximum and minimum conditions for operation must be
observed to assure a system that will give maximum performance
with minimum service.

AIR TEMPERATURE AT

OUTDOOR COIL, °F

Min. Max. Min. Max.

DB

Cool

DB

HeatDBCool

DB

Heat

50 -10 115 75 57

1. Operation below this temperature is permissible for a short period of
time, during morning warm-up.

4. The maximum allowable line length for this product is 75 feet.

AIR TEMPERATURE AT

INDOOR COIL, °F

WB

Cool

DB

Heat

50

1

WB

Cool

72 80

DB

Heat

SECTION III: UNIT INSTALLATION

LOCATION

Before starting the installation, select and check the suitability of the
location for both the indoor and outdoor unit. Observe all limitations and
clearance requirements.

The outdoor unit must have sufficient clearance for air entrance to the
condenser coil, for air discharge, and for service access. See Figure 1.

NOTE: For multiple unit installations, units must be spaced a minimum

of 18 inches apart. (Coil face to coil face.)

If the unit is to be installed on a hot sun exposed roof or a black-topped
ground area, the unit should be raised sufficiently above the roof or
ground to avoid taking the accumulated layer of hot air into the outdoor
unit.

Provide an adequate structural support.

ADD-ON REPLACEMENT/RETROFIT

The following steps should be performed in order to insure proper sys­tem operation and performance.

1. Change-out of the indoor coil to an approved R-22 coil/ condens­ing unit combination with the appropriate metering device.

2. If the outdoor unit is being replaced due to a compressor burnout,
then installation of a 100% activated alumina suction-line filter
drier is required, in addition to the factory installed liquid-line drier.
Operate the system for 10 hours. Monitor the suction drier pres­sure drop. If the pressure drop exceeds 3 psig, replace both the
suction-line and liquid-line driers. After a total of 10 hours run time
where the suction-line pressure drop has not exceeded 3 psig,
replace the liquid line drier, and remove the suction-line drier.
Never leave a suction-line drier in the system longer than 50 hours
of run time.

THERMOSTAT

NEC CLASS 1

WIRING

TO INDOOR
BLOWER

TO COIL

SEAL OPENINGS WITH
PERMAGUM OR EQUIVALENT

NOTE: ALL OUTDOOR WIRING MUST BE WEATHERPROOF

NEC CLASS 2
WIRING

18” FRONT

& SIDES

FIGURE 1: Typical Installation

GROUND INSTALLATION

The unit may be installed at ground level on a solid base that will not
shift or settle, causing strain on the refrigerant lines and possible leaks.
Maintain the clearances shown in Figure 1 and install the unit in a level
position.

Normal operating sound levels may be objectionable if the unit is placed
directly under windows of certain rooms (bedrooms, study, etc.).

Condensate will drain from beneath the coil of the outdoor unit during
the defrost cycle. Normally this condensate may be allowed to drain
directly on the ground.

WEATHERPROOF

DISCONNECT SWITCH

48” OVERHEAD
CLEARANCE

24” SERVICE
ACCESS
CLEARANCE

The outdoor unit should not be installed in an area where mud or
ice could cause personal injury. Remember that condensate will
drip from the unit coil during heat and defrost cycles and that this
condensate will freeze when the temperature of the outdoor air is
below 32°F.

Elevate the unit sufficiently to prevent any blockage of the air entrances
by snow in areas where there will be snow accumulation. Check the
local weather bureau for the expected snow accumulation in your area.

Isolate the unit from rain gutters to avoid any possible wash out of the
foundation.

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170761-UIM-B-0406

ROOF INSTALLATION

When installing units on a roof, the structure must be capable of sup­porting the total weight of the unit, including a pad, lintels, rails, etc.,
which should be used to minimize the transmission of sound or vibra­tion into the conditioned space.

UNIT PLACEMENT

1. Provide a base in the pre-determined location.

2. Remove the shipping carton and inspect for possible damage.

3. Compressor tie-down bolts should remain tightened.

4. Position the unit on the base provided.
NOTE: Heat pumps will defrost periodically resulting in water drainage.

The unit should not be located where water drainage may freeze
and create a hazardous condition - such as sidewalks and
steps.

LIQUID LINE FILTER-DRIER

The heat pumps have a solid core bi-flow filter/drier located on the liquid
line.

NOTE: Replacements for the liquid line drier must be exactly the same

as marked on the original factory drier. See Source 1 for O.E.M.

replacement driers.

Failure to do so or using a substitute drier or a granular type may
result in damage to the equipment.

Filter-Drier

Source 1 Part No.

Apply with Models

YMB / HC3A / HL3A

026 - 25512 - 000 All Sizes

PIPING CONNECTIONS

The outdoor unit must be connected to the indoor coil using field sup­plied refrigerant grade copper tubing that is internally clean and dry.
Units should be installed only with the tubing sizes for approved system
combinations as specified in Tabular Data Sheet. The charge given is
applicable for total tubing lengths up to 15 feet. See Application Data
Part Number 036-61920-001 for installing tubing of longer lengths and
elevation differences.

NOTE: Using a larger than specified line size could result in oil return

problems. Using too small a line will result in loss of capacity
and other problems caused by insufficient refrigerant flow. Slope
horizontal vapor lines at least 1" every 20 feet toward the out­door unit to facilitate proper oil return.

OIL TRAPPING

When the outdoor unit is above the indoor coil oil trapping is necessary.
An oil trap should be provided for every 20 ft. of rise. See Figure 2.

PRECAUTIONS DURING LINE INSTALLATION

1. Install the lines with as few bends as possible. Care must be taken

not to damage the couplings or kink the tubing. Use clean hard
drawn copper tubing where no appreciable amount of bending
around obstruction is necessary. If soft copper must be used, care
must be taken to avoid sharp bends which may cause a restriction.

2. The lines should be installed so that they will not obstruct service

access to the coil, air handling system, or filter.

3. Care must also be taken to isolate the refrigerant lines to minimize

noise transmission from the equipment to the structure.

4. The vapor line must be insulated with a minimum of 1/2" foam rub-

ber insulation (Armaflex or equivalent). Liquid lines that will be
exposed to direct sunlight and/or high temperatures must also be
insulated.

Tape and suspend the refrigerant lines as shown. DO NOT allow tube
metal-to-metal contact. See Figure 3.

5. Use PVC piping as a conduit for all underground installations as

shown in Figure 4. Buried lines should be kept as short as possible
to minimize the build up of liquid refrigerant in the vapor line during
long periods of shutdown

6. Pack fiberglass insulation and a sealing material such as perma-

gum around refrigerant lines where they penetrate a wall to reduce
vibration and to retain some flexibility.

7. See Form 690.01-AD1V for additional piping information.

Sheet Metal Hanger

Liquid
Line

Incorrect

Correct

FIGURE 3: Tubing Hanger

TO INDOOR COIL

LIQUID LINE

PVC

CONDUIT

INSULATED

VAPOR LINE

FIGURE 4: Underground Installation

Insulated Vapor Line

Tape

TO O UTDO OR UNI T

CAP

OUTDOOR COIL

20 Ft.

INDOOR

COIL

20 Ft.

FIGURE 2: Oil Trap

Unitary Products Group 3

10 In.

6 In.

170761-UIM-B-0406

PRECAUTIONS DURING BRAZING OF LINES

All outdoor unit and evaporator coil connections are copper-to-copper
and should be brazed with a phosphorous-copper alloy material such
as Silfos-5 or equivalent. DO NOT use soft solder. The outdoor units
have reusable service valves on both the liquid and vapor connections.
The total system refrigerant charge is retained within the outdoor unit
during shipping and installation. The reusable service valves are pro­vided to evacuate and charge per this instruction.

Serious service problems can be avoided by taking adequate precau­tions to assure an internally clean and dry system.

Dry nitrogen should always be supplied through the tubing while it
is being brazed, because the temperature is high enough to cause
oxidation of the copper unless an inert atmosphere is provided. The
flow of dry nitrogen should continue until the joint has cooled.
Always use a pressure regulator and safety valve to insure that only
low pressure dry nitrogen is introduced into the tubing. Only a small
flow is necessary to displace air and prevent oxidation.

PRECAUTIONS DURING BRAZING SERVICE VALVE

Precautions should be taken to prevent heat damage to service valve
by wrapping a wet rag around it as shown in Figure 5. Also, protect all
painted surfaces, insulation, and plastic base during brazing. After braz­ing cool joint with wet rag.

This is not a backseating valve. The service access port has a
valve core. Opening or closing valve does not close service access
port.

If the valve stem is backed out past the chamfered retaining wall,
the O-ring can be damaged causing leakage or system pressure
could force the valve stem out of the valve body possibly causing
personal injury.

Valve can be opened by removing the plunger cap and fully inserting a
hex wrench into the stem and backing out counter-clockwise until valve
stem just touches the chamfered retaining wall.

Connect the refrigerant lines using the following procedure:

1. Remove the cap and Schrader core from both the liquid and vapor
service valve service ports at the outdoor unit. Connect low pres­sure nitrogen to the liquid line service port.

2. Braze the liquid line to the liquid valve at the outdoor unit. Be sure
to wrap the valve body with a wet rag. Allow the nitrogen to con­tinue flowing. Refer to the Tabular Data Sheet for proper liquid line
sizing.

3. Carefully remove the rubber plugs from the evaporator liquid and
vapor connections at the indoor coil.

FIGURE 5: Heat Protection

The evaporator is pressurized.

4. Braze the liquid line to the evaporator liquid connection. Nitrogen
should be flowing through the evaporator coil.

5. Slide the grommet away from the vapor connection at the indoor
coil. Braze the vapor line to the evaporator vapor connection. After
the connection has cooled, slide the grommet back into original
position. Refer to the Tabular Data Sheet for proper vapor line siz­ing.

6. Protect the vapor valve with a wet rag and braze the vapor line
connection to the outdoor unit. The nitrogen flow should be exiting
the system from the vapor service port connection. After this con­nection has cooled, remove the nitrogen source from the liquid fit­ting service port.

7. Replace the Schrader core in the liquid and vapor valves.

8. Go to “SECTION IV” for TXV installation.

9. Leak test all refrigerant piping connections including the service
port flare caps to be sure they are leak tight. DO NOT OVER­TIGHTEN (between 40 and 60 inch - lbs. maximum).

10. Evacuate the vapor line, evaporator, and the liquid line to 500
microns or less.

NOTE: Line set and indoor coil can be pressurized to 250 psig with dry

nitrogen and leak tested with a bubble type leak detector. Then
release the nitrogen charge.

NOTE: Do not use the system refrigerant in the outdoor unit to purge or

leak test.

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11. Replace cap on service ports. Do not remove the flare caps from
the service ports except when necessary for servicing the system.

Do not connect manifold gauges unless trouble is suspected.
Approximately 3/4 ounce of refrigerant will be lost each time a stan­dard manifold gauge is connected.

12. Release the refrigerant charge into the system. Open both the liq­uid and vapor valves by removing the plunger cap and with an
allen wrench back out counter-clockwise until valve stem just
touches the chamfered retaining wall. See Page 4 "PRECAU­TIONS DURING BRAZING SERVICE VALVE".

13. Replace plunger cap finger tight, then tighten an additional 1/12
turn (1/2 hex flat). Cap must be replaced to prevent leaks.

Never attempt to repair any brazed connections while the system is
under pressure. Personal injury could result.

See "System Charge” section for checking and recording system
charge.

SECTION IV: INST ALLA TIONS REQUIRING
TXV

For installations requiring a TXV, the following are the basic steps for
installation. For detailed instructions, refer to the Installation Instructions
accompanying the TXV kit.

Install TXV kit as follows:

1. First, relieve the holding charge by depressing the Schrader valve
located in the end of the liquid line.

2. After holding charge is completely discharged, loosen and remove
the liquid line fitting from the orifice distributor assembly. Note that
the fitting has right

3. Remove the orifice from the distributor body using a small diame­ter wire or paper clip. Orifice is not used when the TXV assembly
is installed.

4. After orifice is removed, install the thermal expansion valve to the
orifice distributor assembly with supplied fittings. Hand tighten and
turn an additional 1/8 turn to seal. Do not overtighten fittings

5. Reinstall the liquid line to the top of the thermal expansion valve.
Hand modify the liquid line to align with casing opening.

6. Install the TXV equalizer line into the vapor line as follows:
a. Select a location on the vapor line for insertion of the equal-

izer line which will not interfere with TXV bulb placement.

b. Use an awl to punch through the suction tube and insert the

awl to a depth to achieve a 1/8” diameter hole.

7. Install TXV equalizer line in 1/8” hole previously made in vapor
line. Equalizer line should not be bottomed out in vapor line. Insert
equalizer line at least 1/4” in the vapor line. Braze equalizer line
making sure that tube opening is not brazed closed.

hand threads.

.

170761-UIM-B-0406

Dry nitrogen should always be supplied through the tubing while it
is being brazed, because the temperature is high enough to cause
oxidation of the copper unless an inert atmosphere is provided. The
flow of dry nitrogen should continue until the joint has cooled.
Always use a pressure regulator and safety valve to insure that only
low pressure dry nitrogen is introduced into the tubing. Only a small
flow is necessary to displace air and prevent oxidation.

All connections to be brazed are copper-to-copper and should be
brazed with a phosphorous-copper alloy material such as Silfos-5 or
equivalent. DO NOT use soft solder.

Install the TXV bulb to the vapor line near the equalizer line, using the
two bulb clamps furnished with the TXV assembly. Ensure the bulb is
making maximum contact. Refer to TXV installation instruction for view
of bulb location.

In all cases, mount the TXV bulb after vapor line is brazed and has
had sufficient time to cool.

a. Bulb should be installed on a horizontal run of the vapor line if

possible. On lines under 7/8" OD the bulb may be installed on
top of the line. With 7/8" OD and over, the bulb should be
installed at the position of about 2 or 10 o'clock.

b. If bulb installation is made on a vertical run, the bulb should

be located at least 16 inches from any bend, and on the tub­ing sides opposite the plane of the bend. The bulb should be
positioned with the bulb tail at the top, so that the bulb acts as
a reservoir.

c. Bulb should be insulated using thermal insulation pro vided to

protect it from the effect of the surrounding ambient tempera­ture.

SECTION V: ELECTRICAL CONNECTIONS

GENERAL INFORMATION & GROUNDING

Check the electrical supply to be sure that it meets the values specified
on the unit nameplate and wiring label.

Power wiring, control (low voltage) wiring, disconnect switches, and
over current protection must be supplied by the installer. Wire size
should be sized per NEC requirements.

All field wiring must USE COPPER CONDUCTORS ONLY and
be in accordance with Local, National Fire, Safety & Electrical
Codes. This unit must be grounded with a separate ground
wire in accordance with the above codes.

The complete connection diagram and schematic wiring label is located
on the inside surface of the unit service access panel and in Figure 14
of this instruction.

Unitary Products Group 5

170761-UIM-B-0406

FIELD CONNECTIONS POWER WIRING

1. Install the proper size weatherproof disconnect switch outdoors
and within sight of the unit.

2. Remove the screws at the bottom of the corner cover. Slide corner
cover down and remove from unit. See Figure 6.

3. Run power wiring from the disconnect switch to the unit.

4. Remove the service access panel to gain access to the unit wiring.
Route wires from disconnect through power wiring opening pro­vided and into the unit control box as shown in Figure 6.

5. Install the proper size time-delay fuses or circuit breaker, and
make the power supply connections.

6. Energize the crankcase heater if equipped to save time by pre­heating the compressor oil while the remaining installation is com­pleted.

SERVICE
ACCESS
PANEL

CONTROL
WIRING

POWER
WIRING

FIGURE 6: Typical Field Wiring

CORNER
COVER

FIELD CONNECTIONS CONTROL WIRING

1. Route low voltage wiring into bottom of control box as shown in
Figure 5.

2. Replace the corner cover and service access panel that were
removed in Steps 2 and 4 of the “Field Connections Power Wiring”
section.

3. All field wiring to be in accordance with national electrical codes
(NEC) and/or local-city codes.

NOTE: A Start Assist Kit is available and recommended for long line set

applications or in areas of known low voltage problems.

4. Mount the thermostat about 5 ft. above the floor, where it will be
exposed to normal room air circulation. Do not place it on an out­side wall or where it is exposed to the radiant effect from exposed
glass or appliances, drafts from outside doors or supply air grilles.

5. Route the 24-volt control wiring (NEC Class 2) from the outdoor
unit to the indoor unit and thermostat.

NOTE: To eliminate erratic operation, seal the hole in the wall at the

thermostat with permagum or equivalent to prevent air drafts
affecting the operation of in the thermostat.

DEHUMIDIFICATION CONTROL

A dehumidification control accessory 2HU06700124 may be used with
variable speed air handlers or furnaces in high humidity areas. This
control works with the variable speed indoor unit to provide cooling at a
reduced air flow, lowering evaporator temperature and increasing latent
capacity . The humidist at in this control opens the humidist at contact s on
humidity rise. Prior to the installation of the dehumidification control, the
jumper across the HUMIDISTAT terminals on the indoor variable speed
air handler or furnace CFM selection board must be removed.

During cooling, if the relative humidity in the space is higher than the
desired set point of the dehumidification control, the variable speed
blower motor will operate at lower speed until the dehumidification con­trol is satisfied. A 40-60% relative humidity level is recommended to
achieve optimum comfort.

If a dehumidification control is installed, it is recommended that a mini­mum air flow of 325 cfm/ton be supplied at all times.

For additional connection diagrams for all UPG equipment refer to “Low
Voltage System Wiring” document available online at www.upgnet.com
in the Product Catalog Section.

6 Unitary Products Group