ComfortStar Rooftop Package Unit Installation & Owner's Manual

General Description

As the name Rooftop signifies, this unit is generally installed on the top of the roof. Also, the Single Package signifies that both condenser and evaporator are enclosed in a single body (similar to a window type). The unit can be ideal for either rooftop or on-the-ground installation and offers excellent performance, capable of operating up to 115°F of maximum ambient temperature.

The unit is used along with ducts and provides flexible airflow according to installation conditions. It is ideal for single-story and double-story houses due to its high static capability. With its easy installation and simple controlling system, this product is suitable for factories, shopping malls, multiplexes, and hotels.

The unit capacity range is currently from 3 to 5 tons. This publication provides extensive information regarding the design and installation of this system. Please utilize all information to conduct your business efficiently and ensure that specifications, dimensions, and other technical data match the engineering data book before starting the project.

ComfortStar looks forward to your continuing support.

General Information

Inspection

• Read this entire manual before beginning installation procedures.
• Check for damage after the unit is unloaded. Report any damage promptly to the carrier. Do not drop the unit.
• Verify the unit's nameplate to confirm it is correct for the intended application.
• Ensure the power supply is adequate for both the unit and all accessories.

CAUTION: Bodily injury can result from high voltage electrical components and fast-moving fans. Disconnect the electrical supply before installation and servicing to protect against these hazards. If operating checks must be performed with the unit running, the technician must recognize these hazards and proceed safely.

Read this manual carefully before attempting to install, operate, or perform maintenance on this unit. Installation and maintenance should be performed by qualified service technicians only.

Reconnect all grounding devices. All parts of this product capable of conducting electrical current are grounded. If grounding wires, screws, straps, clips, nuts, or washers used to complete a path to ground are removed for service, they must be returned to their original position and properly fastened.

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 may also be used to alert against unsafe practices and where property-damage-only accidents could occur.

NOTE: Warnings and Cautions appear at appropriate locations throughout this manual. Read these carefully.

WARNING: An all-pole disconnection switch with a contact separation of at least 3mm in all poles should be connected in the fixed wiring. The refrigerant circuit temperature will be high; keep the interconnection cable away from the copper tube.

The appliance should not be used by children without supervision. This appliance can be used by children aged 8 years and above, and persons with reduced physical, sensory, or mental capabilities or lack of experience and knowledge, if they have been given supervision or instruction concerning safe use and understand the hazards involved. Children shall not play with the appliance. Cleaning and user maintenance shall not be made by children without supervision.

Disconnect the power supply before cleaning and maintenance.

DISPOSAL: Do not dispose of this product as unsorted municipal waste. Collection of such waste separately for special treatment is necessary. Do not dispose of electrical appliances as unsorted municipal waste; use separate collection facilities. Contact your local government for information regarding collection systems. If electrical appliances are disposed of in landfills or dumps, hazardous substances can leak into groundwater and enter the food chain, damaging health and well-being.

Dimensional Data

Figure 1: This diagram illustrates the physical dimensions and connection points of the rooftop unit. It shows two views (front/side and rear/side) with labels for SUPPLY, RETURN, DRAIN CONNECTION HOLE, CONTROL BOX ACCESS PANEL, HOLE FOR CONTROL WIRES, HOLE FOR POWER WIRES, HOLE FOR OTHER PURPOSE, HIGH PRESSURE GAUGE CONNECTOR, and LOW PRESSURE GAUGE CONNECTOR. Key dimensions are provided in millimeters.

Installation

4.1 Locations and Recommendations

• The unit is designed for outdoor installations only. It may be installed directly on wood flooring or on Class A, Class B, or Class C roof covering material.
• Ensure the unit location allows for adequate service clearance.
• Outdoor coils require an unlimited supply of air.
• Check handling facilities to ensure the safety of personnel and the unit.
• Exercise caution at all times to avoid personal injuries and/or equipment damage.
• The unit must be mounted level for proper drainage of water through the base pan holes.
• The unit must not be exposed to direct roof water runoff.
• Flexible duct connectors must be of a flame-retardant material. All ductwork outside the structure must be insulated and weatherproofed according to local codes.
• Holes through exterior walls must be sealed according to local codes.
• All fabricated outdoor ducts should be as short as possible.

4.2 Rooftop Installation

For rooftop applications using a field-fabricated frame and ducts:

• The roof structure must support the unit's weight and accessories. Install the unit on a solid, level roof curb or an appropriate angle iron frame.
• The frame must be secured by bolting or welding to the roof. Flashing is required.
• Prepare the roof opening in advance of unit installation.
• Secure the ducts to the roof.
• Place the unit on the frame or roof curb.
• Insulate any ductwork outside the structure with at least two (2) inches of insulation and weatherproof it. Ensure a weatherproof seal where the duct enters the structure.
• Secure the unit to the frame or roof curb.
• Complete the installation according to the instructions in the following sections.

Figure 2: Typical Rooftop Installation with Frame

4.3 On-the-Ground Installation

For ground-level installations, position the unit on a pad with a minimum thickness of 100 mm. The pad's length and width should be at least 150 mm greater than the unit's base rails. The unit must be level on the pad. The pad must not contact the structure. Ensure outdoor supply and return air ducts are as short as possible.

Proceed with installation:

• Place the unit on the pad.
• Attach the supply and return air ducts to the unit.
• Insulate any ductwork outside the structure with at least 2 inches of insulation and weatherproof it. Ensure a weatherproof seal where the duct enters the structure.
• Complete the installation according to the instructions in the following sections.

Figure 3: Typical On-the-Ground Installation, showing clearance requirements for service, supply air, drain piping, and electrical controls.

Ductwork and Drainage

4.4 Maximum Foundation Gradient

Note: Ensure the Condensate Drain side is not higher than the other side.

Figure 4: Diagram illustrating the typical maximum foundation gradient, indicating a slight slope (e.g., 10mm or 0.8°) towards the condensate drain side.

4.5 Condensate Drain Piping

Note: Twist drain outlet into the drain connection hole, sheathe the drain pipe, and lock in the snap ring.

Figure 5: Diagram detailing the condensate drain piping connection, showing the drain connection hole, drain outlet, snap ring, and drain pipe.

4.6 Ductwork

All conditioned air ductwork should be insulated to minimize heating and cooling duct losses. Use a minimum of two (2) inches of insulation with a vapor barrier. The outside ductwork must be weatherproofed between the unit and the building.

When attaching ductwork to a horizontal unit, provide a flexible, watertight connection to prevent noise transmission from the unit to the ducts. The flexible connection must be indoors and made of heavy canvas.

NOTE: Do not draw the canvas taut between the solid ducts.

Figure 6: Diagram showing ductwork connection with a flexible canvas connector between the unit duct flange and the field duct, with a note to weatherproof the seam.

Electrical Wiring

Electrical Power

It is important that proper electrical power is available for the unit. Voltage variation should remain within the limits stamped on the unit nameplate.

Disconnect Switch

Provide an approved weatherproof disconnect either on the side of the unit or within close proximity and within sight of the unit.

Over Current Protection

The branch circuit feeding the unit must be protected as shown on the unit rating plate.

Power Wiring

Power supply lines must be run in weather-tight conduit to the disconnect and into the unit's bottom control box. Provide strain relief for all conduit with suitable connectors. Use flexible conduit supports where vibration transmission might cause noise problems within the building structure. Ensure all connections are made tight.

Control Wiring (Class II)

Low voltage control wiring should not be run in conduit with power wiring unless Class 1 wire of proper voltage rating is used. Make connections as shown on the unit wiring diagram. Do not short thermostat wires, as this will damage the control transformer.

Suggestion: Choose a non-programmed electrical thermostat series such as CSW23B or CSW25B.

IMPORTANT: Upon completion of wiring, check all electrical connections, including factory wiring within the unit, to ensure they are tight. Replace and secure all electrical box covers and access doors before leaving the unit or turning on the power.

CAUTION: If the supply cord is damaged, it must be replaced by the manufacturer, its service agent, or a similarly qualified person to avoid a hazard.

An all-pole disconnection device with at least 3mm separation distance in all poles and a residual current device (RCD) with a rating of above 10mA shall be incorporated in the fixed wiring according to national rules. The appliance shall be installed in accordance with national wiring regulations.

NOTE: To access the control box, twist off the screws on the access panel, then lift it off.

Wiring Diagram Description: The document includes several wiring diagrams illustrating the connections for the main control board, compressor, fans, sensors, contactors, and transformer. These diagrams are specific to different models and configurations (e.g., 36000Btu/h, 48000Btu/h, 60000Btu/h, single-phase, three-phase). A table typically lists the component codes, part names, and wire colors/connections. For example, 'COMP' refers to the Compressor, 'FAN1' to the Indoor Fan, 'FAN2' to the Outdoor Fan, 'CAP1'/'CAP2' to fan capacitors, 'KM1' to the AC Contactor, 'T5'/'T6' to transformers, and 'RT2' to a temperature sensor. The diagrams show how these components are wired to the main control board and to the thermostat.

Operating Conditions

For proper performance, run the unit under the following temperature conditions:

• Cooling operation: Outdoor temperature: 70 to 115°F, Room temperature: 62 to 86°F

Caution: Room relative humidity less than 80%. If the unit operates in excess of this figure, the surface of the unit may attract condensation.

Physical Data

Table 7-1 provides detailed physical specifications for the 36000, 48000, and 60000 Btu/h models, including:

• Nominal Capacity (Btu/h)
• Nominal Tonnage
• SEER
• Refrigerant type
• Dimensions (Length, Width, Height)
• Condenser Coil Data (Fins per inch, Tube diameter, Circuitry Type)
• Evaporator Coil Data (Rows, Fins per inch, Tube diameter, Refrigerant control)
• Condenser Fan Data (Quantity, Fan diameter, Type, Drive type, No. Speeds, Number of motors, RPM, Nominal total CFM)
• Evap Fan Data (Quantity, Fan diameter, Type, Drive type, No. Speeds, Number of motors, RPM, Nominal total CFM)

Wind Pressure Curve

The document includes graphs illustrating the wind pressure curves for different models:

• 36000 Btu/h 208-230V~ 60Hz: A graph plotting External static pressure (Pa) against Air volume (m³/h), showing a curve labeled 'L'.
• 48000 Btu/h 208-230V~ 60Hz: A similar graph plotting External static pressure (Pa) against Air volume (m³/h), showing a curve labeled 'M'.
• 60000 Btu/h 208-230V~ 60Hz and 60000 Btu/h 208-230V 3N~ 60Hz: A graph plotting External static pressure (Pa) against Air volume (m³/h), showing a curve labeled 'H'.

Performance Data

Detailed cooling performance data tables are provided for various models and operating conditions (Ambient Temperature vs. Entering Wet Bulb Temperature, Air Flow). These tables list:

• Total Gross Capacity (TGC)
• Sensible Heat Capacity (SHC)
• Input Power (INPUT[kW])

Data is presented for 36000 Btu/h, 48000 Btu/h, 60000 Btu/h (1-phase), and 60000 Btu/h (3-phase) units.

Start-Up

Packaging and Components Checklist

• Is the unit properly located and level with the proper clearance?
• Is the duct work correctly sized, run, taped, insulated, and weatherproofed?
• Is the wiring properly sized and run according to the unit wiring diagram?
• Are all wiring connections tight?
• Has the unit been properly grounded and fused?
• Have air conditioning systems been checked for charge and leaks?
• Do the condenser fan and indoor blower turn free and are they tight on the shafts?
• Has the indoor blower speed been determined and set correctly?
• Are all covers and access panels in place?

CAUTION

Before starting the system on the cooling cycle, turn the thermostat switch to OFF and close the unit disconnect switch. This energizes the compressor crankcase heater to vaporize liquid refrigerant, preventing foaming and potential compressor damage. Allow the crankcase heater to operate for a minimum of eight (8) hours if installed.

Starting the Unit in the Cooling Mode

Set the thermostat system switch to COOL and set the thermostat to a temperature below the room temperature. The condenser (outdoor) fan motor, compressor, and evaporator (indoor) fan motor will operate automatically.

Voltage Check

With the compressor operating, check the line voltage at the unit. Ensure it is within the range specified on the unit nameplate. If low voltage is encountered, check the supply line size and length.

Cooling Shut Down

Place the system selector to OFF or set the thermostat to a temperature above room temperature. Do not de-energize the main power disconnect unless servicing the unit, as power is needed for the compressor crankcase heater.

System Operation

LED Display

The control system uses LEDs to display fault codes. A quick flashing of LEDs indicates a system problem. Refer to the table below for operational codes:

Low Pressure Switch

The control monitors the low pressure switch, which is normally closed. If the low pressure switch opens during initial power-up, the compressor will be de-energized. If the low pressure protection triggers three times within 20 minutes, the control will reset after power cycling. The control ignores the low pressure switch input during defrost operations, for 4 minutes after defrost, and for the first 5 minutes of compressor operation.

Indications of Proper Operation

When the LEDs are lit (in any state), it indicates the system is running properly.

Maintenance

Routine Maintenance by Owner

Owners can perform periodic maintenance such as cleaning air filters, unit cabinet, condenser coil, and general unit inspection.

Cleaning the Air Filter

1. Dismantle the air filter: Twist off screws, remove the filter baffle, and drag out the filter.
2. Clean the air filter: Use a vacuum cleaner or pure water. For heavy dust, use a soft brush and mild detergent. Dry thoroughly.
3. Re-install the air filter.

CAUTION: Do not dry the air filter under direct sunshine or with fire.

Figure 7: Illustration of the air filter and filter baffle.

Figure 8: Instructions for cleaning the air filter, showing the air-in side facing up for vacuuming and down for water cleaning.

Condenser Coil

Unfiltered air can clog the condenser coil. Clean the coil vertically with a soft-bristled brush, stroking with the fins. Keep vegetation away from the coil area.

Maintenance Performed by Serviceman (Cooling Season)

The manufacturer recommends a qualified serviceman inspect the system annually or as needed. Areas to be checked include:

• Filters
• Motors and drive system components
• Economizer gaskets (for possible replacement)
• Safety controls (for mechanical cleaning)
• Electrical components and wiring (for possible replacement and connection tightness)
• Condensate drain (for cleaning)
• Unit duct connections (to ensure they are physically sound and sealed to the unit casing)
• Unit mounting support (for structural integrity)
• Overall unit condition (for obvious deterioration)

CAUTION: Do not operate the unit without the evaporator fan access panel in place. Reinstalling it is crucial to prevent severe personal injury or death.