ARUF**14** / ASPT**14** AIR HANDLERS INSTALLATION & OPERATING INSTRUCTIONS

1 Important Safety Instructions

This section outlines critical safety information. Failure to follow these instructions increases the risk of personal injury, property damage, and product damage.

HIGH VOLTAGE: Disconnect all power before servicing or installing. Multiple power sources may be present. Failure to do so may cause property damage, personal injury, or death.

FLAMMABLE MATERIALS: Do not store combustible materials or use gasoline or other flammable liquids/vapors near the unit.

POWER SUPPLY: This product is factory-shipped for use with 208/240/1/60 electrical power supply only. Do not reconfigure for other power supplies.

CAUTION: Safety clothing, including hand and eye protection, is recommended during installation or servicing. Observe special safety requirements for specific areas.

ELECTRICAL GROUND: Ensure an uninterrupted, unbroken electrical ground connection to the building's electrical service panel. Follow National Electric Code (NEC) or Canadian Electric Code (CSA) standards.

CARBON MONOXIDE POISONING HAZARD: Special warning for installations in enclosed areas like garages or utility rooms. Ensure adequate outside ventilation if carbon monoxide producing devices are operated nearby, as CO can cause serious illness or death.

2 Shipping Inspection

Transport the unit upright. Inspect upon receipt for shipping damage. Verify model number, specifications, and electrical characteristics are correct before installation. Claims for transportation damage are the responsibility of the carrier.

• 2.1 Parts: Inspect all components for presence and integrity. Report missing parts immediately. Use only factory-authorized replacement parts.
• 2.2 Handling: Use caution when transporting. Do not use shipping straps or sharp objects. A two-wheel hand truck or carrying by cabinet corners is recommended.

3 Codes & Regulations

Installation must comply with applicable national, local, and state codes and regulations. The manufacturer is not responsible for installations violating codes. Follow EPA regulations regarding refrigerant handling and disposal.

4 Replacement Parts

Order parts using the complete product model and serial numbers. Parts are available through your contractor or local distributor. Contact homeowner support for distributor locations.

5 Pre-Installation Considerations

• 5.1 Preparation: Read all instructions carefully before installation. Gather all necessary tools, hardware, and supplies.
• 5.2 System Matches: Use only manufacturer-approved systems listed by AHRI. Unmatched systems are not permitted.
• 5.3 Interconnecting Tubing: Minimize refrigerant tubing length. Allow sufficient length for coil removal for servicing.
• 5.4 Clearances: Maintain a minimum of 24 inches service clearance in front of the unit. Consult codes for electrical wiring clearances. Elevate units in wet areas. Install with a positive slope for condensate lines (1/4" per foot).
• 5.5 Horizontal Applications: If installed above a finished living space, install a secondary drain pan and route the drain line where condensate discharge is visible.

6 Installation Location

These air handlers are designed for indoor installation only.

The ARUF**14** and ASPT**14** models can be installed in upflow, downflow, horizontal left, or horizontal right orientations. The unit may ship in upflow or horizontal left orientation.

Field modifications for orientation are not mandatory, but removing the horizontal drip shield, side drain pan, and drain pan extension can improve efficiency.

Side Drain Pan and Extension Removal: Remove screws securing the drip shield support brackets. Unsnap the side drain pan. Drain port (A) is primary; port (a) is secondary. Cover removed side drain port opening with the accessory drain port plug (DPK1) if the side pan is removed.

6.1 Upflow Installation: No field modifications are mandatory.

6.2 Horizontal Left Installation: Install as shown in Figure 4. Remove red plugs from the side drain pan before connecting condensate drain pipes. Use plugs to close vertical drain pan ports. The bottom right drain connection in the side drain pan is primary; the bottom left is secondary.

For horizontal left installations in environments with over 65% relative humidity and external static pressure above 0.5" e.s.p., a condensate kit (Table 2) may be required.

6.3 Horizontal Right Installation / Downflow Installation: A DFK (Downflow Kit) is required for downflow installations to prevent coil pan sweating. See Table 3 for correct DFK models.

Side drain pan extension removal is required for downflow and horizontal right applications for most models, except ARUF-47D14, ARUF61D14, ASPT61D14, ASPT49D14.

Downflow Installation Steps:

1. Remove blower and coil access panels.
2. Slide coil assembly out using the drain pan (do not use manifolds or flowrator).
3. Remove center support if applicable (21" wide cabinets).
4. Position unit in downflow orientation.
5. Slide coil assembly back into cabinet on downflow brackets.
6. Reinstall center support.
7. Reinstall access panels.

Drain Connections for Horizontal Right: Bottom right drain connection in side drain pan is primary. Bottom left is secondary. Remove red plugs before connecting pipes.

Drain Connections for Downflow: Bottom left drain connection in vertical drain pan is primary. Bottom right is secondary. Remove red plugs before connecting pipes.

7 Refrigerant Lines

Route refrigerant tubing for adequate service access. Avoid installing the air handler in locations that violate condenser instructions. Insulate the unit in unconditioned areas with high ambient temperature/humidity to prevent sweating.

7.1 Tubing Size: Follow condenser/heat pump specifications.

7.2 Tubing Preparation: Ensure cut ends are round, burr-free, and clean to prevent leaks. Use clean gloves when handling coil assemblies.

7.3 Special Instructions: Units with flowrator pistons may require piston changes for mismatched applications. Consult piston kit charts. Use a heat shield when brazing to protect the unit's finish and components.

WARNING: Quenching cloth is recommended when brazing near painted surfaces. Use brazing alloy of 5% minimum silver content.

WARNING: Product is shipped with R410A and dry nitrogen under pressure. Use appropriate service tools.

CAUTION: Avoid applying excessive heat to tubes, as it can melt them. Match torch heat to tube size.

7.4 Tubing Connections for Flowrator Model: Loosen 13/16" nut to release tracer gas. Remove piston to verify size. Remove spin closure on suction line.

7.5 Tubing Connections for TXV Models: TXV models have pre-installed TXV bulbs. Remove access valve cap, depress stem to check for leaks. Remove spin closure on liquid and suction tubes. Insert lines and slide grommets back. Braze joints and quench with water or a wet rag.

7.6 ASPT**14** Models with Non-Adjustable TXV: Charge by subcooling only. See Table 4 for applicable models.

7.7 Thermal Expansion Valve System Adjustment: Run system for 10 minutes in cooling. Use service gauge manifold and thermometer. Check subcooling (7-9°F) and superheat (7-9°F). Adjust TXV by turning the valve stem (clockwise to increase, counter-clockwise to decrease) to achieve desired superheat. Add charge to raise subcooling if low. Remove charge if subcooling is high and superheat is low.

Subcool Formula: SAT. LIQUID LINE TEMP. - LIQUID LINE TEMP.

Superheat Formula: SUCT. LINE TEMP. - SAT. SUCT. TEMP.

ASPT models with TXV are tuned for 16 SEER Heat Pump. Adjustments may be needed for other outdoor models or if subcool/superheat deviates.

See Saturated Pressure/Temperature Charts for R-22 and R-410A.

8 Condensate Drain Lines

The coil drain pan has primary and secondary 3/4" NPT female connections. Use 3/4" NPT male connectors (PVC or metal), hand-tightened to 37 in-lbs. Ensure drain pan hole is unobstructed.

Insulate drain lines inside the building to prevent sweating. Install a condensate trap (Figure 12) as close to the coil as practical to ensure proper drainage and prevent air from being drawn back into the unit. Use a condensate removal pump if necessary, ensuring it has a float switch and a trap between the unit and the pump.

CAUTION: If the secondary drain is not installed, the secondary access must be plugged.

NOTE: Evaporator coils use oils that may dissolve styrofoam and plastics. Ensure condensate pumps or float switches do not contain these materials.

Install an auxiliary drain pan for installations above finished living spaces or where overflow could cause damage.

9 Ductwork

The air handler is designed for a complete supply and return ductwork system.

CAUTION: Do not operate the product without all ductwork attached.

Size ductwork for 350-450 CFM per ton of cooling with static pressure not exceeding 0.5" w.c. Refer to ACCA Manuals for sizing. Use flame retardant ductwork sealed to prevent leakage.

NOTE: Downflow applications with electric heat require an L-shaped supply duct without outlets below the heater.

9.1 Return Ductwork: Do not locate return ductwork in areas that can introduce toxic fumes or odors. Connect to the air handler bottom (upflow configuration).

10 Return Air Filters

An air filter is required for each installation. Filters can be installed in the air handler's factory rails or externally. For factory rails, use nominal sizes 16x20x1", 20x20x1", or 24x20x1".

11 Electric Heat

Refer to the electric heat kit installation manual. Only HKS series heat kits are permitted. Heating mode temperature rise depends on airflow, supply voltage, and heat kit size (kW). Use Tables 5, 6, and 7 to determine temperature rise.

Temperature Rise Formula: TR = (kW x 3412) x (Voltage Correction) / (1.08 X CFM)

NOTE: Temperature Rise Tables can also estimate airflow delivery. Set thermostat to maximum heat and measure temperature rise.

12 Electrical and Control Wiring

Route all wiring through provided knockouts. Do not alter the cabinet for wiring.

HIGH VOLTAGE: Disconnect all power before servicing. Multiple power sources may be present.

12.1 Building Electrical Service Inspection: Unit is designed for single-phase supply only. Verify supply voltage matches unit nameplate requirements.

12.2 Wire Sizing: Use wire rated for Minimum Circuit Ampacity (MCA) from the unit's rating plate. Refer to NEC/CSA for sizing. Ensure no more than 2% voltage drop. Check wire insulation temperature ratings.

12.3 Maximum Overcurrent Protection (MOP): Install an NEC/CEC approved overcurrent protection device (fuse or circuit breaker). Size larger than MCA but not exceeding MOP.

12.4 Electrical Connections – Supply Voltage: Use only copper conductors. Knockouts are provided for entry. Use adapter rings and strain relief as required by UL1995 and local codes.

• 12.4.1 Air Handler Only (Non-Heat Kit Models): Connect building supply to stripped black and red wires. Attach ground screw. Use appropriately sized solderless connectors.
• 12.4.2 Air Handler - Non-Circuit Breaker Heat Kits: Use terminal block provided with HKS kit. Refer to HKS Installation Manual.
• 12.4.3 Air Handler With Circuit Breaker Heat Kit: Access panel cover allows installation of circuit breaker. Breakers have lugs for power supply connection. Refer to HKS Installation Instructions.

12.5 Low Voltage Connections: Connects air handler to thermostat and condenser using 24V control voltage. Use minimum 18AWG copper conductors for up to 100 feet. Wiring can enter through the top or sides.

12.5.1 Thermostats: Follow thermostat manufacturer's instructions. Second-stage heat can be achieved with multi-stage thermostats or outdoor thermostats.

12.6 Speed Tap Adjustment: ARUF**14** models have multi-speed PSC motors. Wire colors (black=high, blue=medium, red=low) indicate speed. Swap wires at the "COM" terminal on the control board to change speed.

ASPT**14** models have energy-efficient blower motors. Adjust CFM by changing 24 VAC leads to the desired speed tap. Some speed taps may not be allowable for electric heat applications (refer to Table 6).

13 Achieving 1.4% Low Leakage Rate

Ensure all gaskets are intact. Panels must be in place and secured. Gaskets must be positioned correctly for 1.4% leakage. Tubing must be leak-free. Condensate lines must be trapped and pitched. Low voltage wiring must be connected. Auxiliary drain must be installed and pitched. Unit must be protected from damage. Return air must be from a clean environment, free from odors, flammable vapors, or combustion products.

14 Start-Up Procedure

Before start-up:

• Ensure electrical wires are properly sized and connections are tight.
• All panels must be in place and secured.
• Tubing must be leak-free.
• Condensate line must be trapped and pitched.
• Low voltage wiring must be properly connected.
• Auxiliary drain must be installed and pitched.
• Unit must be protected from physical damage.
• Return air must be from a clean environment, free from odors, flammable vapors, or combustion products.

15 Regular Maintenance

The user is responsible for maintaining the circulating air filter(s) monthly. A certified service technician must perform all other services.

IMPORTANT NOTE: Ensure washers on thumb screws for filter access remain in place after re-installation.

16 Airflow Data

Tables 11 and 12 provide airflow data (CFM) based on static pressure and blower speed for ARUF and ASPT models, respectively. Airflow data is at 230V without an air filter. Adjustments are noted for horizontal orientations.

17 Air Handler Low Voltage Connections

This section details wiring diagrams for various configurations, including single-stage cooling and heat pump with single or two-stage electric heating. It covers connections between the room thermostat, air handler, and condensing unit, with optional outdoor thermostat connections. Refer to diagrams for jumper settings for blower speed control.

IMPORTANT: When matching ASPT air handlers to single-speed cooling/heat pump units, connect "Y" from the thermostat to "Y2" on the low voltage terminal board.

18 Wiring Diagrams

Detailed wiring diagrams are provided for ARUF and ASPT air handlers, covering low voltage connections for cooling units with and without heat kits, and for heat pump units with optional heat kits. Diagrams illustrate connections to room thermostats, outdoor thermostats, and condensing units. Specific notes on wire colors, component codes, and wiring procedures are included.

NOTE: Wiring is subject to change. Always refer to the wiring diagram on the unit for the most up-to-date wiring.

3-Phase Heat Kit

When installing a 3-phase heat kit, ensure the speed tap meets or exceeds the minimum blower speed (MBS) specified for the air handler/heat kit combination. Mark an "X" on the serial plate for the installed heat kit.

AIR HANDLER HOMEOWNER'S ROUTINE MAINTENANCE RECOMMENDATIONS

REPLACE OR CLEAN FILTER: Never operate without a filter. Clean or replace filters monthly. High-efficiency filters are recommended.

MOTORS: Indoor and outdoor fan motors are permanently lubricated.

HIGH VOLTAGE: Disconnect power before servicing.

ALUMINUM INDOOR COIL CLEANING (QUALIFIED SERVICER ONLY): Use water to flush the coil. Avoid corrosive chemicals that can damage aluminum coils.

BEFORE YOU CALL YOUR SERVICER: Check thermostat settings, wait 15 minutes, check electrical panel for tripped breakers/fuses, confirm disconnect switch is closed, check for outdoor unit obstructions, ensure air inlets/outlets are clear, check filter, and listen for unusual noises.