Standard ECM Single Piece 4 Position Air Handlers

General Information

The AHE single piece air handler series provides flexibility for installation in any position. This unit may be used for upflow, downflow, horizontal right, or horizontal left applications. These units may be located in a closet, utility room, attic, crawl space, or basement. These versatile models may be used for cooling or heat pump operation with or without electric heat. Top and side power wiring and control wiring, accessible screw terminals for control wiring, easy to install drain connections, and electric heaters all combine to make the installation easy and minimize installation cost.

Electric Heat Kits

Electric heat kits are available as field installed accessories:

• Single phase kits available from 2.5 kW to 25kW
• Three phase kits available from 10kW to 25kW

A Brand Label (available from Distribution) may be applied to the center of the blower access panel.

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.

! WARNING Improper installation, adjustment, alteration, or maintenance may create a condition where the operation of the product could cause personal injury or property damage. Refer to this manual for assistance, or for additional information, consult a qualified contractor, installer, or service agency.

! CAUTION This product must be installed in strict compliance with the installation instructions and any applicable local, state, and national codes including, but not limited to building, electrical, and mechanical codes.

! WARNING FIRE OR ELECTRICAL HAZARD Failure to follow the safety warnings exactly could result in serious injury, death or property damage. A fire or electrical hazard may result causing property damage, personal injury or loss of life.

Safety Requirements

1. This air handler should be installed in accordance with all national and local building/safety codes and requirements, local plumbing or wastewater codes, and other applicable codes.
2. Read and follow all instructions in this manual. Failure to do so can result in air handler malfunction, death, personal injury and/or property damage.
3. Install this air handler only in a location and position as specified in the "Unit Installation" section of these instructions.
4. The air handler is not to be used for temporary heating of buildings or structures under construction.
5. Always install the air handler to operate within the air handler's intended maximum outlet air temperature.
6. Provide clearances from combustible materials as listed in the "Clearances" section of this manual.
7. Provide clearances for servicing ensuring that service access is allowed for electric heaters and blower.
8. Check the unit's rating plate and power supply to be sure that the electrical characteristics match.
9. Air handler shall be installed so the electrical components are protected from water.
10. Installing and servicing heating/cooling equipment can be hazardous due to the electrical components. Only trained and qualified personnel should install, repair, or service heating/cooling equipment. Untrained service personnel can perform basic maintenance functions such as cleaning and replacing the air filters. When working on heating/cooling equipment, observe the precautions in the manuals and on the labels attached to the unit and other safety precautions that may apply.
11. These instructions cover minimum requirements and conform to existing national standards and safety codes. In some instances these instructions exceed certain local codes and ordinances, especially those who have not kept up with changing residential and non-HUD modular home construction practices. These instructions are required as a minimum for a safe installation.

! CAUTION These air handlers should be transported & handled in an upright, upflow position. Failure to do so may result in unit damage and personal injury. Configuration conversions should be done at site of installation.

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 freight bill. A separate request for inspection by the carrier's agent should be made in writing. Before installation, the unit should be checked for screws or bolts, which may have loosened in transit. There are no shipping or spacer brackets which need to be removed.

Check to be sure all accessories such as heater kits and coils are available. Installation of these accessories or field conversion of the unit should be accomplished before setting the unit in place or connecting any wiring, electric heat, ducts or piping.

Figure 1: Return Duct Attachment & Component Location depicts the air handler with labels for the blower compartment, coil compartment, vertical and horizontal drain pans, refrigerant line connections, primary and secondary drains, filter door, and return air duct. It illustrates how to attach ductwork with screws, keeping them within 5/8" of the sides and back of the air handler.

Dimensions and Clearances

Figure 2: Dimensions & Duct Connection Dimensions shows a diagram of the air handler with dimensions labeled A through F, indicating height, width, depth, and duct connection points. It also shows the location of the service disconnect panel, filter access, and drain pan connections for horizontal applications.

Table 1: Dimensions

Notes: 1. All dimensions are in inches. 2. Actual size (conduit size).

Clearances must be taken into consideration and provided for as follows:

1. Refrigerant piping and connections - minimum 12" recommended.
2. Maintenance and servicing access - minimum 36" from front of unit recommended for blower motor / coil replacement.
3. Condensate drain lines routed to clear filter and panel access.
4. Filter removal - minimum 36" recommended.
5. The ductwork and plenum connected to this unit are designed for zero clearance to combustible materials.
6. A combustible floor base accessory is available for downflow applications of this unit, if required by local code.

Location

Location is usually predetermined. Check with owner's or dealer's installation plans. If location has not been decided, consider the following in choosing a suitable location:

1. Select a location with adequate structural support, space for service access, clearance for air return and supply duct connections.
2. Using hanging brackets to wall mount this single piece air handler unit is not recommended.
3. Normal operating sound levels may be objectionable if the air handler is placed directly over some rooms such as bedrooms, study, etc.
4. Select a location that will permit installation of condensate line to an open drain or outdoors allowing condensate to drain away from structure.

Unit Installation

Unit Sizing

1. The size of the unit should be based on an acceptable heat loss or gain calculation for the structure. ACCA, Manual J or other approved methods may be used.
2. Only connect the air handler to a duct system which has an external static pressure within the allowable range.
3. Airflow must be within the minimum and maximum limits approved for electric heat and indoor coils.
4. When an air handler is installed so that supply ducts carry air circulated by the air handler to areas outside the space containing the air handler, the return air shall also be handled by duct(s) sealed to the air handler casing and terminating in the space to be cooled/ heated.
5. Refer to the unit rating plate for the air handler model number, and then see the dimensions page of this instruction for supply air plenum dimensions. The plenum must be installed according to the instructions.
6. The installer must check available supply power and verify that it is within the normal operating voltage range for the unit. The acceptable voltage range for these units is as follows: Air Handler Voltage 208/230-1-60. Normal Operating Voltage Range: 187-253. (Rated in accordance with ARI Standard 110, utilization range "A").

Configuration Conversions

Figure 3: Typical Installation illustrates the unit's orientation for upflow, downflow, horizontal right, and horizontal left configurations.

Horizontal Left Conversion

1. With air handler in vertical position remove all access panels and the tubing connection panel.
2. Slide the coil assembly out of the air handler.
3. Remove and reposition the condensate deflector. See Figures 4 & 5.
4. Rotate air handler 180° so the blower outlet is facing down.
5. Reinstall the coil assembly on the coil support brackets.
6. Reattach tubing connection panel.
7. Remove the drain pan plugs from the horizontal drain pan and screw them into the vertical, A-coil drain pan.
8. Reattach access panels.

Downflow Conversion

A downflow floor base is available for this air handler. Refer to instructions supplied with the kit for installation.

1. With air handler in vertical position remove all access panels and the tubing connection panel.
2. Slide the coil assembly out of the air handler.
3. Rotate air handler 180° so the blower outlet is facing down.
4. Reinstall the coil assembly on the coil support brackets.
5. Reattach tubing connection panel.
6. Reattach access panels.

Condensate Deflector

The condensate deflector comes attached to the vertical, A-coil drain pan. If installing the unit in the upflow or downflow position, no modification is necessary.

For units to be installed in the horizontal position, the condensate deflector needs to be removed from the vertical drain pan and placed on the horizontal drain pan. Remove the condensate deflector and the S-clips that attach it to the vertical drain pan. Relocate the deflector and S-clips onto the horizontal drain pan. Line up with the coil support bracket. See Figure 5 for details. This positions the deflector below the feeder tubes to channel the condensate into the drain pan.

Air Handler Configuration

These air handler units are supplied ready to be installed in an upflow and horizontal right position. If the unit requires either downflow or horizontal left airflow configurations, the unit must have the coil assembly repositioned.

NOTICE For both right and left horizontal applications, the condensate deflector needs to be removed from the vertical drain pan and placed on the horizontal drain pan. See "Condensate Deflector" section for details.

NOTICE Conversion must be made before brazing the refrigerant line connections to the coil.

Figure 4: Condensate Deflector on Vertical Drain Pan shows the condensate deflector attached to the vertical drain pan using S-clips.

Figure 5: Condensate Deflector on Horizontal Drain Pan Edge illustrates the condensate deflector relocated to the horizontal drain pan edge, secured by S-clips on the horizontal pan, positioned below the feeder tubes.

Ductwork and Connections

The vast majority of problems encountered with heating and cooling systems can be linked to improperly designed or installed duct systems. It is therefore highly important to the success of an installation that the duct system be properly designed and installed.

When installing a central air return grille in or near the living space, it is advisable to design the ductwork so that the grille is not in direct line with the opening in the unit. One or two elbows and acoustical duct liner may assure a quieter installation and system. Where return air duct is short, or where sound may be a problem, sound absorbing accoustical duct liner should be used inside the duct.

! WARNING Do not bring in return air from a location which could introduce hazardous substances into the airflow.

Insulation of duct work is a must where it runs through an unheated space during the heating season or through an uncooled space during the cooling season. The use of a vapor barrier is recommended to prevent absorption of moisture from the surrounding air into the insulation.

Duct work should be fabricated and installed in accordance with local and/or national codes. This includes the standards of the National Fire Protection Association for Installation of Air-Conditioning and Ventilating Systems, NFPA No. 90B. They should be sized in accordance with National Environmental System Contractors Association Manual K, or whichever is applicable.

! CAUTION This unit is not designed for non-ducted (freeblow) applications. Do not operate without ductwork attached to unit.

Use flexible duct connectors to minimize the transmission of vibration/ noise into the conditioned space. If electric heat is used, non-flammable material must be used.

All ducts should be suspended using flexible hangers and never fastened directly to the structure.

Horizontal Suspension

These air handlers may be suspended in horizontal applications. It is recommended to use angle steel support brackets with minimum 3/8" threaded rods, supporting the unit from the bottom. Attach the threaded rods at the locations shown in Figure 7.

NOTICE When assembling the support structure, make sure to size to provide clearance for access door removal.

Figure 7: Horizontal Suspension shows diagrams illustrating suspension support locations for horizontal applications, detailing minimum requirements for threaded rods and angle brackets, along with a table showing dimensions X and H for cabinet sizes B, C, and D.

Duct Flanges

Four flanges are provided to assist in positioning and attaching ductwork to the air handler. These flanges are rotated down for shipment. In order to use the flanges, remove the screw holding an individual flange, rotate the flange so it is in the upward position, and reinstall the screw. Repeat this for all 4 flanges. If the flanges are not used, they must remain in the down position as shipped.

Figure 8: Duct Attachment shows the duct attachment flanges.

Figure 9: Ductwork Transition illustrates a recommended transition piece and the suggested location of a block-off plate.

Unit Connections

There are several ways to handle the supply and return air duct connections. The location and sizing of the connections depends on the situation and the method best suited to the installation.

The supply air duct should be properly sized by use of a transition to match unit opening. Refer to Table 1 for air handler unit inlet and outlet dimensions.

! CAUTION Use 1/2" screws to connect ductwork to bottom of unit. Longer screws will pierce the drain pan and cause leakage. If pilot holes are drilled, drill only though field duct and unit bottom flange.

Ductwork that is not designed to match the supply air opening can cause turbulence inside the plenum. This turbulence can change the air flow patterns across the electric heater limit switches. If the factory suggested transition cannot be fabricated, it is recommended that a block off plate (approximately 8" high and running the full width of the plenum) be attached to the supply opening. Refer to Figure 9 as a visual aid. The use of this block off plate will enable better air circulation across the limit switches.

Air Filters

Return air filters are required and must be field supplied. Filtration can be accomplished external to the unit or the integral filter rack may be used. A 1" filter access rack has been built into the unit. Remove filter access cover shown. Install proper size filter. Standard 1" size permanent or throw away filter may be used, or, permanent washable filters are available using model numbers: 1PF0601, 602 or 603BK. See Table 2 for filter size.

! CAUTION Equipment should never be operated without filters.

TXV OR ORIFICE METERING DEVICES

All air handlers are shipped with flex coils, meaning that the indoor coil does not have a factory installed metering device, in order to accommodate a variety of application choices. An R-22, R-410A TXV, or orifice must be installed. Refer to the "Outdoor Unit Technical Guide" to verify the correct metering device for the AC or HP unit installed. It is recommended to install the metering device prior to brazing line sets. DO NOT install TXV sensing bulb onto suction line header until brazing is complete and suction line is cool.

Refer to the instructions in the installation manuals provided with the TXV kit and outdoor unit for more information.

Figure 10: Thermal Expansion Valve (TXV) shows a diagram of the TXV assembly, labeling the vapor line, liquid line, equalizer line, distributor body, and the TXV bulb.

Figure 11: Proper Bulb Location illustrates the correct placement of the TXV bulb on the suction line, noting it should be covered completely with insulation.

Refrigerant Line Connection

! CAUTION COIL UNDER PRESSURE. Relieve pressure by depressing schrader core.

! CAUTION Dry nitrogen should always be supplied through the tubing while it is being brazed, because the temperature required 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.

NOTICE Route the refrigerant lines to the coil in a manner that will not obstruct service access to the coil, air handling system, or filter.

Connect lines as follows:

1. Suction and liquid line connections are made outside the cabinet. Leave the tubing connection panel attached to the cabinet with the tubes protruding through it. Coil access panel should be removed for brazing. The lines are swedged to receive the field installed refrigeration tubing.
2. Wrap a water soaked rag around the coil connection tubes inside the cabinet to avoid damaging the TXV.
3. Remove grommets where tubes exit the cabinet to prevent burning them during brazing.
4. Purge refrigerant lines with dry nitrogen.
5. Braze the suction and liquid lines.
6. Re-attach the grommets to the lines carefully to prevent air leakage.
7. Suction line must be insulated.
8. Attach TXV bulb to suction header and insulate with form tape provided.
9. Attach the coil access panel to the cabinet.

NOTICE ALWAYS evacuate the coil and refrigeration tubing to 500 microns before opening outdoor unit service valves.

Refer to Outdoor unit Installation Manual for evacuation, leak check and charging instructions.

Lines should be sound isolated by using appropriate hangers or strapping.

All indoor 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.

Drain Connections

All drain lines should be trapped a minimum of three inches, should be pitched away from unit drain pan and should be no smaller than the coil drain connection.

! CAUTION Threaded drain connection should be hand-tightened, plus no more than 1/16 turn. Do not use pipe thread compound.

Route the drain line so that it does not interfere with accessibility to the coil, air handling system or filter and will not be exposed to freezing temperatures. See Figure 2 for drain connection locations.

! CAUTION When the coil is installed in an attic or above a finished ceiling, an auxiliary drain pan should be provided under the coil if specified by local building codes. When this exterior secondary drain pan is used that drain should be piped to a location that will give the occupant a visual warning that the primary drain is clogged.

Coils should be installed level or pitched slightly toward the drain end. Suggested pitch should not exceed 1/4 inch per foot of coil.

The drain pan connections are designed to ASTM Standard D 2466 Schedule 40. Use 3/4" PVC or steel threaded pipe. Since the drains are not subject to any pressure it is not necessary to use Schedule 40 pipe for drain lines.

Electric Heater Installation

If the air handler requires electric heat, install the electric heat kit according to the installation instructions included with the kit. After installing the kit, mark the air handler nameplate to designate the heater kit that was installed. If no heater is installed, mark the name plate appropriately to indicate that no heat kit is installed.

Use only 6HK heater kits, as listed on air handler name plate and in these instructions. Use data from Tables 4 through 9 for information on required minimum motor speed tap to be used for heating operation, maximum over-current protection device required and minimum electrical supply wiring size required - for listed combination of Air Handler and Heater Kit.

Line Power Connections

Power may be brought into the unit through the supply air end of the unit (top when unit is vertical) or the left side panel. Use the hole appropriate to the unit's orientation in each installation to bring conduit from the disconnect. The power lead conduit should be terminated at the electrical control box. Refer to Tables 6 through 9 to determine proper wire sizing. To minimize air leakage, seal the wiring entry point at the outside of the unit.

All electrical connections to air handlers must be made with copper conductors. Direct connection of aluminum wiring to air handlers is not approved.

If aluminum conductors are present, all applicable local and national codes must be followed when converting from aluminum to copper conductors prior to connection to the air handler.

If wire other than uncoated (non-plated), 75° C ambient, copper wire is used, consult applicable tables of the National Electric Code (ANSI/ NFPA 70). The chosen conductor and connections all must meet or exceed the amperage rating of the overcurrent protector (circuit breaker or fuse) in the circuit.

Additionally, existing aluminum wire within the structure must be sized correctly for the application according to National Electric Code and local codes. Caution must be used when sizing aluminum rather than copper conductors, as aluminum conductors are rated for less current than copper conductors of the same size.

Figure 12: Blower Delay Control Board shows a diagram of the control board with labeled terminals.

Figure 13: Line Power Connections provides schematic diagrams for single-phase and three-phase electric heat options, illustrating single-source and multi-source power connections, including component codes.

Low Voltage Control Connections

The 24 volt power supply is provided by an internally wired low voltage transformer which is standard on all models. However, if the unit is connected to a 208 volt power supply, the low voltage transformer must be rewired to the 208 volt tap. See the unit wiring label.

Field supplied low voltage wiring can exit the unit on the top right hand corner or the right hand side panel. Refer to Figure 2.

Remove desired knockout and pierce foil faced insulation to allow wiring to pass through. Use as small of a hole as possible to minimize air leakage. Install a 7/8" plastic bushing in the selected hole and keep low voltage wiring as short as possible inside the control box.

To further minimize air leakage, seal the wiring entry point at the outside of the unit.

The field wiring is to be connected at the pigtails supplied with the control board harness. Refer to SECTIONS XI and XII for system wiring.

NOTICE All wiring must comply with local and national electrical code requirements. Read and heed all unit caution labels.

NOTICE It is possible to vary the amount of electric heat turned on during the defrost cycle of a heat pump. Standard wiring will only bring on the first stage of electric heat during defrost. See Table 5 for additional information on heat during defrost cycle.

Blower Speed Connections

Adjust blower motor speed to provide airflow within the minimum and maximum limits approved for indoor coil, electric heat and outdoor unit. Speed tap adjustments are made at the motor terminal block. Airflow data is shown in Table 10.

Connect motor wires to motor speed tap receptacle for speed desired. See unit wiring label for motor wiring details.

Figure 14: Blower Speed Connections shows the wiring diagram for an ECM High Efficiency Motor, illustrating connections to the control board, transformer, and blower fan motor.

Unit Data

Table 2: Physical and Electrical Data

Table 2: Physical and Electrical Data

Notes: 1. Field supplied.

Table 3: Electrical Data - Cooling Only

Notes: 1. FLA = Full Load Amps. 2. MOP = Maximum Overcurrent Protection device; must be HACR type circuit breaker or time delay fuse. 3. 75°C, copper wire only. If wire other than non-plated, 75°C ambient, copper wire is used, consult applicable tables of the NEC and local codes.

Table 4: Electric Heat: Minimum Fan Speed

Notes: 1. (0,1) - 0 = no circuit breaker OR 1 = with circuit breaker. 2. (1,2) - 1 = with circuit breaker, no breaker jumper bar OR 2 = with circuit breaker & breaker jumper bar.

Table 5: Electrical Heat Performance Data: 208/230-1-60 & 208/230-3-60

Table 6: Electrical Data For Single Source Power Supply: 208/230-1-60

Table 6: Electrical Data For Single Source Power Supply: 208/230-1-60 (Continued)

Table 7: Electrical Data For Multi-Source Power Supply: 208/230-1-60

Notes: 1. MOP = Maximum Overcurrent Protection device; must be HACR type circuit breaker or time delay fuse. 2. Stated sizes are for 75°C, copper wire only. If wire other than non-plated, 75°C ambient, copper wire is used, consult applicable tables of the NEC and local codes. 3. 1st Circuit includes the blower motor amps.

Table 8: Electrical Data For Single Source Power Supply: 208/230-3-60

Table 9: Electrical Data For Multi-Source Power Supply: 208/230-3-60

Table 10: Air Flow Data (CFM)¹

Notes: 1. Air handler units have been tested to UL 1995 / CSA 22.2 standards up to 0.30" wc. external static pressure. Dry coil conditions only, tested without filters. For optimal performance, external static pressures of 0.2" to 0.3" are recommended. Applications above 0.3" are not recommended. Airflow data shown is from testing performed at 230V. AHE units use a standard ECM motor, and there is minimal variation of airflow at other distribution voltage values. The above data can be used for airflow at other distribution voltages.

Maintenance

Coil Cleaning

If the coil needs to be cleaned, it can be washed with a mild indoor coil cleaner. Follow directions from coil cleaner.

Lubrication

The bearings of the blower motor are permanently lubricated.

Condensate Drains

During the cooling season check the condensate drain lines to be sure that condensate is flowing from the primary drain but not from the secondary drain. If condensate ever flows from the secondary drain the unit should be promptly shut off and the condensate pan and drains cleaned to insure a free flowing primary drain.

Wiring Diagrams

Figure 15: Wiring Diagram - ECM - Single Phase Heat Kits provides detailed wiring schematics for single-phase heat kits, illustrating connections for various heater kit models and blower speed settings.

Figure 16: Wiring Diagram - 3 Phase Heat Kits presents wiring diagrams for three-phase electric heat kits, showing connections for different heater kit models.

Figure 17: Typical Wiring Diagram - ECM shows a typical wiring diagram for an ECM unit, including connections for the blower motor, transformer, and control board, with instructions on changing heat pump defrost cycle settings.

Figure 18: Typical Thermostat Wiring for 2-Stage Heat Pump with ECM Blower Motor illustrates thermostat wiring configurations for a 2-stage heat pump with an ECM blower motor, showing connections for thermostats and the air handler.

Start Up Sheet

Residential Air Handler with Electric Heat Start-Up Sheet. Proper start-up is critical to customer comfort and equipment longevity.

Electric Heat

Details for electric heat kit installation, including model number, serial number, rated KW, number of elements, measured amperage, measured voltage, heating return air dry bulb temperature, heating supply air dry bulb temperature, and air temperature rise.

Clean Up Job Site

• Job site has been cleaned, indoor and outdoor debris removed from job site
• Tools have been removed from unit
• All panels have been installed

Unit Operation and Cycle Test

• Operate the unit through continuous fan cycles from the thermostat, noting and correcting any problems
• Operate the unit through cooling cycles from the thermostat, noting and correcting any problems
• Operate the unit through mechanical heating cycles from the thermostat, noting and correcting any problems
• Operate the unit through emergency heating cycles from the thermostat, noting and correcting any problems

Owner Education

• Provide owner with the owner's manual
• Explain operation of system to equipment owner
• Explain thermostat use and programming (if applicable) to owner
• Explain the importance of regular filter replacement and equipment maintenance

Comments and Additional Job Details

Blank section for additional notes.