Ameristar M4AC6 Assembly instructions

Installer’s Guide
April 2020
SAFETY WARNING
Only qualified personnel should install and service the equipment. The installation, starting up, and servicing of heating, ventilating,
and air-conditioning equipment can be hazardous and requires specific knowledge and training. Improperly installed, adjusted or
altered equipment by an unqualified person could result in death or serious injury. When working on the equipment, observe all pre-
cautions in the literature and on the tags, stickers, and labels that are attached to the equipment.
M4AC6018A1000A
M4AC6024A1000A
M4AC6030A1000A
M4AC6036A1000A
M4AC6042A1000A
M4AC6048A1000A
Note: “Graphics in this document are for representation only.
Actual model may differ in appearance.”
Split System Cooling
M4AC6
88-M4PW003-1B-EN

2 88-M4PW003-1B-EN
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WARNING
This information is intended for use by individuals possessing
adequate backgrounds of electrical and mechanical experience.
Any attempt to repair a central air conditioning product may result in
personal injury and/or property damage. The manufacture or seller
cannot be responsible for the interpretation of this information, nor
can it assume any liability in connection with its use.
These units use R-410A refrigerant which operates at 50 to 70%
higher pressures than R-22. Use only R-410A approved service
equipment. Refrigerant cylinders are painted a “Rose” color to
indicate the type of refrigerant and may contain a “dip” tube to allow
for charging of liquid refrigerant into the system. All R-410A systems
use a POE oil that readily absorbs moisture from the atmosphere.
To limit this “hygroscopic” action, the system should remain sealed
whenever possible. If a system has been open to the atmosphere
for more than 4 hours, the compressor oil must be replaced. Never
break a vacuum with air and always change the driers when open-
ing the system for component replacement. For specific handling
concerns with R-410A and POE oil reference Retrofit Bulletins SS-
APG006-EN and APP-APG011-EN.
Extreme caution should be exercised when opening the
Liquid Line Service Valve. Turn counterclockwise until
the valve stem just touches the rolled edge. No torque is
required. Failure to follow this warning will result in abrupt
release of system charge and may result in personal injury
and /or property damage.
UNIT CONTAINS R-410A REFRIGERANT!
R-410A operating pressures exceed the limit of R-22. Proper ser-
vice equipment is required. Failure to use proper service tools may
result in equipment damage or personal injury.
USE ONLY R-410A REFRIGERANT AND APPROVED POE COM-
PRESSOR OIL.
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LIVE ELECTRICAL COMPONENTS!
During installation, testing, servicing, and troubleshooting of
this product, it may be necessary to work with live electrical
components. Failure to follow all electrical safety precau-
tions when exposed to live electrical components could
result in death or serious injury.
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WARNING
The appliance is not to be used by persons (including
children) with reduced physical, sensory or mental capabili-
ties, or lack of experience and knowledge, unless they have
been given supervision or instruction.
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Children should be supervised to ensure that they do
not play with the appliance.
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If using existing refrigerant lines make certain that all
joints are brazed, not soldered.
CAUTION
Scroll compressor dome temperatures may be hot. Do
not touch the top of compressor; it may cause minor
to severe burning.
CAUTION
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WARNING
IMPORTANT — This Document is customer property and is to
remain with this unit. Please return to service information pack
upon completion of work.
These instructions do not cover all variations in systems, nor
do they provide for every possible contingency to be met in
connection with the installation. Should further information
be desired, or should particular problems arise which are not
sufficiently covered for the purchaser’s purposes, the matter
should be referred to your installing dealer or local distributor.
Table of Contents
Section 1. Safety...........................................................................................................................................................2
Section 2. Unit Location Considerations.......................................................................................................................3
Section 3. Unit Preparation...........................................................................................................................................4
Section 4. Setting the Unit.............................................................................................................................................5
Section 5. Refrigerant Line Considerations...................................................................................................................5
Section 6. Refrigerant Line Routing...............................................................................................................................6
Section 7. Refrigerant Line Brazing...............................................................................................................................7
Section 8. Refrigerant Line Leak Check........................................................................................................................9
Section 9. Evacuation....................................................................................................................................................9
Section 10. Service Valves...........................................................................................................................................10
Section 11. Electrical - Low Voltage.............................................................................................................................10
Section 12. Electrical - High Voltage.............................................................................................................................12
Section 13. Start Up......................................................................................................................................................12
Section 14. System Charge Adjustment.......................................................................................................................13
Section 15. Checkout Procedures and Troubleshooting...............................................................................................17
Section 16. Refrigeration Circuits..................................................................................................................................21
ALL phases of this installation must comply with NATIONAL,
STATE AND LOCAL CODES
Section 1. Safety

88-M4PW003-1B-EN 3
D
H
W
50’
Max
Vertical
Change
Standard
Line Set
150’ Max
TOTAL Line Length
50’
Max
Vertical
Change
Table 2.1
Section 2. Unit Location Considerations
2.1 Unit Dimensions and Weight
2.2 Refrigerant Piping Limits
1. The maximum TOTAL length of refriger-
ant lines from outdoor to indoor unit should
NOT exceed 150 feet (including lift).
2. The maximum vertical change should not
exceed 50 feet.
3. Service valve connection diameters are
shown in Table 5.1.
Note: For other line lengths, Refer to Refriger-
ant Piping Application Guide, SS-APG006-EN
or Refrigerant Piping Software Program, 32-
3312-03 (or latest revision).
When mounting the outdoor unit on a roof, be
sure the roof will support the unit’s weight.
Properly selected isolation is recommended to
alleviate sound or vibration transmission to the
building structure.
Unit Dimensions and Weight
Models H x D x W (in) Weight* (lb)
M4AC6018A
29 x 30 x 33 161
M4AC6024A
29 x 30 x 33 162
M4AC6030A
42 x 30 x 37 184
M4AC6036A
37 x 34 x 37 212
M4AC6042A
45 x 34 x 37 272
M4AC6048A
45 x 34 x 37 272
* Weight values are estimated.

4 88-M4PW003-1B-EN
Min. 12” to
Shrubbery
Avoid Install
Near Bedrooms
Min 5’ Unrestricted
Access Panel
Min 3’
Unrestricted
2.3 Suggested Locations for Best Reliability
Ensure the top discharge area is unrestricted for
at least five (5) feet above the unit.
Three (3) feet clearance must be provided in
front of the control box (access panels) and any
other side requiring service.
Do not locate close to bedrooms as operational
sounds may be objectionable.
Min. 12” to
Shrubbery
Min. 12”
to Wall
Position the outdoor unit a minimum of 12” from
any wall or surrounding shrubbery to ensure
adequate airflow.
Outdoor unit location must be far enough away
from any structure to prevent excess roof runoff
water from pouring directly on the unit.
STEP 2 - To remove the unit from the pallet,
remove tabs by cutting with a sharp tool.
Section 3. Unit Preparation
3.1 Prepare The Unit For Installation
STEP 1 - Check for damage and report prompt-
ly to the carrier any damage found to the unit.
2.4 Coastal Considerations
If installed within one mile of salt water, including seacoasts and inland waterways, models without factory sup-
plied Seacoast Salt Shields require the addition of BAYSEAC001 (Seacoast Kit) at installation time.

88-M4PW003-1B-EN 5
Section 4. Setting the Unit
4.1 Pad Installation
When installing the unit on a support pad, such
as a concrete slab, consider the following:
• The pad should be at least 1” larger than the
unit on all sides.
• The pad must be separate from any structure.
• The pad must be level.
• The pad should be high enough above grade
to allow for drainage.
• The pad location must comply with National,
State, and Local codes.
Line Sizes Service Valve Connection Sizes
Model Vapor
Line
Liquid
Line
Vapor Line
Connection
Liquid Line
Connection
M4AC6018A 3/4 3/8 3/4 3/8
M4AC6024A 3/4 3/8 3/4 3/8
M4AC6030A 3/4 3/8 3/4 3/8
M4AC6036A 7/8 3/8 3/4 3/8
M4AC6042A 7/8 3/8 3/4 3/8
M4AC6048A 7/8 3/8 3/4 3/8
Section 5. Refrigerant Line Considerations
5.1 Refrigerant Line and Service Valve Connection Sizes
Table 5.1
Line Length
5.3 Required Refrigerant Line Length
5.2 Factory Charge
Determine required line length and lift. You will
need this later in STEP 2 of Section 14.
Total Line Length = __________ Ft.
Total Vertical Change (lift) = __________ Ft.
The outdoor condensing units are factory charged with the system charge required for the outdoor condensing
unit, ten (10) feet of tested connecting line, and the smallest rated indoor evaporative coil match. Always verify
proper system charge via subcooling (TXV/EEV) or superheat (xed orice) per the unit nameplate.

6 88-M4PW003-1B-EN
5.5 Reuse Existing Refrigerant Lines
For retrofit applications, where the existing
indoor evaporator coil and/or refrigerant lines
will be used, the following precautions should
be taken:
• Ensure that the indoor evaporator coil and
refrigerant lines are the correct size.
• Ensure that the refrigerant lines are free of
leaks, acid, and oil.
CAUTION
If using existing refrigerant lines make certain that
all joints are brazed, not soldered.
Section 6. Refrigerant Line Routing
6.1 Precautions
Important: Take precautions to prevent noise
within the building structure due to vibration
transmission from the refrigerant lines.
For Example:
• When the refrigerant lines have to be fastened to floor joists or other framing in a structure, use isolation type
hangers.
• Isolation hangers should also be used when refrigerant lines are run in stud spaces or enclosed ceilings.
• Where the refrigerant lines run through a wall or sill, they should be insulated and isolated.
• Isolate the lines from all ductwork.
• Minimize the number of 90º turns.
Comply with National, State, and Local Codes when
isolating line sets from joists, rafters, walls, or other
structural elements.
Isolation From Joist/Rafter
Side View
8 Feet Maximum
Secure Vapor line from joists using isolators every 8 ft. Secure
Liquid Line directly to Vapor line using tape, wire, or other appro-
priate method every 8 ft.
Joist/Rafter
Isolator
Line Set
8 Feet Maximum
5.4 Refrigerant Line Insulation
Important: The Vapor Line must always be
insulated. DO NOT allow the Liquid Line and
Vapor Line to come in direct (metal to metal)
contact.
Vapor Line
Liquid Line
Insulation

88-M4PW003-1B-EN 7
Isolation In Wall Spaces
Side View
Wall
Isolator
Line Set
8 Feet Maximum
Secure Vapor Line using isolators every 8 ft. Secure Liquid Line
directly to Vapor Line using tape, wire, or other appropriate
method every 8 ft.
8 Feet Maximum
Isolation Through Wall DO NOT hang line sets from ductwork
Sealant
Insulation
Vapor Line
Wall
Ductwork
Isolator
Line Set
Section 7. Refrigerant Line Brazing
7.1 Braze The Refrigerant Lines
STEP 1 - Remove caps or plugs. Use a debur-
ing tool to debur the pipe ends. Clean both
internal and external surfaces of the tubing
using an emery cloth.

8 88-M4PW003-1B-EN
STEP 2 - Remove the pressure tap cap and
valve cores from both service valves.
STEP 3 - Purge the refrigerant lines and indoor
coil with dry nitrogen.
STEP 4 - Wrap a wet rag around the valve body
to avoid heat damage and continue the dry nitro-
gen purge.
Braze the refrigerant lines to the service valves.
For units shipped with a field-installed external
drier, check liquid line filter drier’s directional flow
arrow to confirm correct direction of refrigeration
flow (away from outdoor unit and toward evapo-
rator coil) as illustrated. Braze the filter drier to
the Liquid Line.
Continue the dry nitrogen purge. Do not remove
the wet rag until all brazing is completed.
Important: Remove the wet rag before stopping
the dry nitrogen purge.
Note: Install drier in Liquid Line.
NOTE:NOTE: Precautions should be taken to avoidPrecautions should be taken to avoid
heat damage to basepan during brazing. It isheat damage to basepan during brazing. It is
recommended to keep the flame directly off ofrecommended to keep the flame directly off of
the basepan.the basepan.
3-4” from valve

88-M4PW003-1B-EN 9
STEP 5 - Replace the pressure tap valve cores
after the service valves have cooled.
STEP 2 - Check for leaks by using a soapy solu-
tion or bubbles at each brazed location.
Remove nitrogren pressure and repair any leaks
before continuing.
Section 8. Refrigerant Line Leak Check
8.1 Check For Leaks
STEP 1 - Pressurize the refrigerant lines and
evaporator coil to 150 PSIG using dry nitrogen.
150 PSIG
Section 9. Evacuation
9.1 Evacuate the Refrigerant Lines and Indoor Coil
Important: Do not open the service valves until
the refrigerant lines and indoor coil leak check
and evacuation are complete.
STEP 1 - Evacuate until the micron gauge reads
no higher than 350 microns, then close off the
valve to the vacuum pump.
0350
Microns
ON OFF

10 88-M4PW003-1B-EN
STEP 2 - Observe the micron gauge. Evacuation
is complete if the micron gauge does not rise
above 500 microns in one (1) minute.
Once evacuation is complete blank off the
vacuum pump and micron gauge, and close the
valves on the manifold gauge set.
1 MIN.
Section 10. Service Valves
10.1 Open the Gas Service Valve
CAP
1/4 TURN ONLY
COUNTERCLOCKWISE
FOR FULL OPEN
POSITION
VALVE STEM
GAS LINE CONNECTION
UNIT SIDE
OF VALVE
PRESSURE TAP PORT
Important: Leak check and evacuation must be
completed before opening the service valves.
NOTE: Do not vent refrigerant gases into the
atmosphere
STEP 1 - Remove valve stem cap.
STEP 2 - Using an adjustable wrench, turn valve
stem 1/4 turn counterclockwise to the fully open
position.
STEP 3 - Replace the valve stem cap to prevent
leaks. Tighten finger tight plus an additional 1/6
turn.
10.1 Open the Liquid Service Valve
Important: Leak check and evacuation must be
completed before opening the service valves.
STEP 1 - Remove service valve cap.
STEP 2 - Fully insert 3/16” hex wrench into the
stem and back out counterclockwise until valve
stem just touches the rolled edge (approximately
five (5) turns.)
STEP 3 - Replace the valve cap to prevent
leaks. Tighten finger tight plus an additional 1/6
turn.
Cap
Rolled Edge to
Captivate Stem
Hex Headed
Valve System
Service Port
3/16” Hex Wrench
Unit Side
of Service
Valve
Extreme caution should be exercised when
opening the Liquid Line Service Valve. Turn
counterclockwise until the valve stem just
touches the rolled edge. No torque is required.
Failure to follow this warning will result in abrupt
release of system charge and may result in
personal injury and /or property damage.
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WARNING
Section 11. Electrical - Low Voltage
11.1 Low Voltage Maximum Wire Length
Table 11.1 defines the maximum total length of
low voltage wiring from the outdoor unit, to the
indoor unit, and to the thermostat.
Table 11.1
24 VOLTS
WIRE SIZE MAX. WIRE LENGTH
18 AWG 150 Ft.
16 AWG 225 Ft.
14 AWG 300 Ft.