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P.O. Box 400 • Cordele, Georgia 31010 • 156 Seedling Drive • Cordele, Georgia 31015 (229) 273-3636 • Fax (229) 273-5154 E-mail: marvairsales@airxcel.com • Internet: www.Marvair.com The most current version of this manual can be found at www.Marvair.com. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
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For information on the efficiency, cooling and heating performance, please refer to the Product Data Sheets. The most current version of all literature can be found on our website at www.Marvair.com. If you are installing the heat pump unit, first read Chapter 1 and scan the entire manual before beginning the installation as described in Chapter 2.
All internal wiring is complete. Marvair MAA heat pump models are available in a wide variety of styles and configurations to meet the various ventilation and cooling requirements. For school classrooms, models are available to comply with the ASHRAE 62-1999 standard, “Ventilation for Acceptable Indoor Air Quality.”...
30 Special Variation $ = Special Configuration Not Covered by Model Nomenclature Note: Not all options are available with all configurations. Contact your Marvair sales representative for configuration details and feature compatibility. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
1.5 General Operation Refrigerant Cycle Marvair heat pumps use R-410A refrigerant in a conventional vapor-compression refrigeration cycle to transfer heat. In the cooling mode, a double blower assembly blows indoor air across the evaporator (indoor coil). Liquid refrigerant passing through the evaporator is boiled into gas by heat removed from the air.
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Thermostat must provide the fan “G” signal to HVAC to activate the indoor blower. Economizer Status: The economizer board has contacts that when used with the Marvair CommStat 4 Telecom HVAC Controller, change state to provide feedback to the CommStat 4 to indicate when the HVAC is in economizer mode verses mechanical cooling mode.
The heat pump is factory wired to be normally open. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
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Electric Heat During Defrost (EHDD) and “No” selected for the S-Circuit, the electric heat (EH) output will be energized during a defrost cycle to supply heat while the coil defrosts. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
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LPS fault, and initiate the 3 minute anti-short cycle timer. If two LPS faults occur within a one hour period, the control will enter a LPS lockout condition Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
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HPS High Pressure switch terminals are the high pressure switch input. LPS Loss of Charge switch terminals are the loss of charge switch input. DS The DS terminals are the defrost sensor input. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
Adjustable Outdoor Thermostat Will not allow electric resistance heat to be energized unless the outdoor temperature is below the desired set point. Field or factory installed. Available on all Marvair units. P/N 93934 Single Point Feed When multiple internal disconnects are used, single point feed permits only one field power supply to heat pump.
(i.e., economizer cooling). If the outdoor ambient is too hot or humid, the sensor will place the actuator in the closed or minimum open position and activate mechanical cooling. The compressor is locked out during the economizer cooling mode. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
The thermistor senses the air temperature entering the structure, and provides a signal to the economizer controller for modulating the position of the damper. Nominal resistance of the sensor at 77°F is 3000 ohms. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
Failure to observe and follow Warnings and Cautions and these Instructions could result in death, bodily injury or property damage. Read this manual and follow its instructions and adhere to all Cautions and Warnings in the manual and on the Marvair unit.
2.3 Installation Materials Installation Kits Marvair MAA Heat Pumps have built-in mounting flanges that function as side brackets. All models require and are shipped with a bottom mounting bracket. On units with the "N" ventilation option, there is a fresh air hood factory installed behind the lower front panel.
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1” (25mm) thick filter. The return filter grille is not recommended for use with the MAA heat pumps with economizers. Additional Items Needed: Additional hardware and miscellaneous supplies (not furnished by Marvair ) are needed for installation. ®...
Galvanized metal duct extensions should be used to simplify connections to duct work and grilles. Use fabric boots to prevent the transmission of vibration through the duct system. The fabric must be U.L. rated (UL-181) to a minimum of 197 Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
For example, on wooden structures, use 3/8 x 2-1/2 inch all-thread lag screws. The screws must penetrate the center of the wall stud. Drill a pilot hole in the stud to prevent it from splitting. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
10. To minimize sound transmission, a latex based, insulating foam seal may be applied between the duct extensions and the frame for the wall openings. NOTE: DO NOT USE THE FOAM ON ANY UNITS WITH ELECTRIC RESISTANT HEATERS. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
All electrical work must meet the requirements of local codes and ordinances. Work should be done only by qualified persons. CAUTION This Marvair Heat Pump may incorporate an internal crankcase heater for compressor protection. The crankcase heater must be energized for at least 24 hours prior to starting the compressor.
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Terminals 8 & 10 on the Marvair with economizer can be connected to a normally closed smoke alarm or fire stat to cause equipment shutdown when the circuit is opened. (Remove factory jumper).
Various thermostats can be used to control the heat pump. The thermostat may have a fan switch with an Automatic and On positions, a system switch with Heat, Cool, and Off positions, and an emergency heat position with lights. The spec sheets have detailed description of the various Marvair ®...
2. Raise the heating set point temperature to a setting which is higher than the room temperature. The fan and compressor should cycle on after time delay (standard on Marvair heat pumps with an economizer and optional on all other Marvair units) has cycled.
68ºF and no higher than 78ºF. Allow the refrigerant system to stabilize for at least five minutes and adjust the temperature as desired. Adjustment Knob Positive (Red) Negative (Black) Figure 7 - Desired Temperature Set Point Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
3.4 Ventilation System Set-Up: Manual Fresh Air System (Configuration N). This is the standard ventilation system in Marvair heat pumps. Fresh air ventilation by means of a damper can provide up to 15% of rated air flow of outside air. The damper has four positions corresponding to 0, 5, 10 and 15% of rated air flow of outside air.
The motorized damper, Configuration B, can be controlled by an optional relay that allows additional external control with a choice of 24, 120 or 240V coils to regulate fresh air ventilation in response to a control located remote from the Marvair heat pump. Marvair Wall Mount Heat Pump I&O Manual...
Please read the Chapter 1 for basic information about the unit. Marvair Heat Pumps are thoroughly tested before they are shipped from the factory. However, it is possible that a defect may escape undetected, or damage may have occurred during transportation. However, the great majority of problems result from installation errors.
Test components (especially the compressor) for shorts. 4. Excessively high or low supply volt- 4. Note voltage range limitations specific to the age or phase loss (3ø only). compressor troubleshooting section. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
A short circuit at a high voltages indicates a motor defect. Do not do this test under vacuum. 4. On single phase models, check the capacitor by substitution. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
The indoor evaporator fan motor is cycled by the blower timed delay relay. See Figure 9. Due to the large number of variations and options available for the Marvair heat pumps, it is not practical to include every possible wiring schematic in this manual. The following schematics are typical. Included in each heat pump is the electrical schematic for that unit.
Regularly check the primary and secondary condensate drains. The secondary drain has a stand pipe. An obstruction will force water to dump into the middle of the unit and drain out the sides of the Marvair Heat Pump, causing discoloration of the side panels. If discoloration is noted, service the drains.
5 Years Compressor If any part of your Marvair, Inc. unit fails within 90 days of the commencement of the warranty, Marvair, Inc. will furnish without charge, EX Works, Cordele, Georgia, the required replacement part and pay for the labor to replace the part in accordance with the Marvair, Inc. Flat Rate Labor Guidelines.
The 1" (25.4 mm) clearance must extend on all sides of the supply duct for the first 3 feet (1 meter) from the unit. IMPORTANT: Marvair requires a minimum of 1" (25.4 mm) from the surface of any supply ducts to combustible material for the first 3 feet (1 meter) of the duct.
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15. Place the wiring diagram provided with the heater kit inside the zip lock bag which is affixed to the back side of the control box cover. 16. Replace the control box cover, the bottom front cover and the top front panel. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
Is the correct filter(s) in place and clean? ................. ❒Yes ❒No Refrigerant Piping Is there any evidence of refrigerant leaks (oil leaks, etc.)? ..........❒Yes ❒No If leaks are found, report them to Marvair Warranty Service Dept. Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
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If using a standard thermostat, Set the Control to ON, Mode to Cooling, Fan to Auto (other controls, set appropriately for cooling mode). Note: The reversing valve (Marvair Heat Pumps) is energized for “Cooling”. The “O” signal from the thermostat is Required.
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719 / 3 = 239.7 Volts (Average Voltage) 239.7 (Average Voltage) – 235 (Maximum Deviation) = 4.7 (Deviation Difference) (4.7 x 100)/239.7 = 1.95% Voltage Imbalance (Less than 2% is acceptable) Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
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Is the Compressor On? ...................... ❒Yes ❒No Is the Condenser Fan (CFM) On? ..................❒Yes ❒No Is the Heater Off? (Clamp an AmpProbe on one leg of the heater contactor to verify) ... ❒Yes ❒No Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
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Return Air Temperature (RAT) wb (used to calculate RH% of Return Air) ºF Supply Air Temperature (SAT) db (Acceptable Range 55ºF (+/- 3ºF) ºF Return Air Temperature (SAT) wb (used to calculate RH% of Supply Air) ºF Marvair Wall Mount Heat Pump I&O Manual 11/2021 New...
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If using a standard thermostat, Set the Control to ON, Mode to Heat, Fan to Auto (other controls, set appropriately for heating mode). Note: The reversing valve (Marvair Heat Pumps) is de-energized for “Cooling”. The “O” signal from the thermostat is Not Required.
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Mechanical Heat Lockout, start heating with Only Electric heat. Notice: system did not turn off. “Mechanical Heat” turned Off and “Electric Heat” turned On. Note: The “S” Circuit (Marvair Heat Pump control board) must be set to “Yes”, to allow Mechanical Heat Lockout.
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** Please provide a description of the issue in the Notes section below and if you need help, call: Marvair Technical and Warranty Support: (888) 726-2734 This number is manned M-F, 8:00am to 5:00pm eastern. Technical support calls will be returned M-F, 5:00pm to 8:00pm eastern.
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