Classic HVPA & HVPSA Heat Pumps MAINTENANCE & SERVICE Models HVPA24-30-36-42-49-60 & HVPSA36-42-49-60 CAUTION!! Read all instructions before use. Retain this manual for future reference. This equipment should be installed and serviced only by a trained professional HVAC service person. Due to continuous product improvement, use only the current issue of this manual. The latest version can be downloaded from the Marvair website - www.marvair.com. Manufactured By: Marvair Division of AIRXCEL®, Inc. ® P.O.
SECTION 15700 HEATING, VENTILATING AND AIR CONDITIONING EQUIPMENT MAINTENANCE & SERVICE MANUAL FOR CLASSICTM HEAT PUMP TABLE OF CONTENTS Chapter 1.1 Description Page General Description ..................................................................3 1.2 Model Identification ..................................................................4 2.1 Start-up Instructions .................................................................5 2.2 Ventilation System Calibration...............................
SECTION 15700 HEATING, VENTILATING AND AIR CONDITIONING EQUIPMENT The purpose of this manual is to provide instructions for maintenance and service for the Marvair® Classic™ series of heat pumps. In addition to this manual, there are other pieces of literature available from Marvair. The Product Manual covers the installation of the unit and various accessories and the initial start-up of the unit. An overview of the product line can be found in the Classic Product Data Sheets.
1.2 MODEL IDENTIFICATION The ClassicTM heat pump identification numbering system is shown below. The model identification number is on the data label. The data label is at the bottom of the of left side panel. IMPORTANT WHEN CLASSIC SYSTEMS ARE INSTALLED, MODEL NUMBER AND SERIAL NUMBERS ARE TO BE RECORDED AND MAINTAINED IN A LOCATION FOR IMMEDIATE ACCESS WHEN REQUESTING FURTHER INFORMATION. Classic HVPA & HVPSA M&S 8.
2.1 START-UP PROCEDURE Important: If your unit has a crankcase heater be sure that the crankcase heater has been energized for at least 24 hours prior to start-up of the unit. Double check all electrical connections before applying power. 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.
4. Set the time delay in the Classic™ Heat Pump with Economizer control box to 3 minutes. Check the enthalpy changeover setting of the H205A or dry bulb sensor, and reset it if needed. Refer to the Owner’s manual for instructions on setting the H205A or dry bulb sensor. 5. Slowly lower the thermostat’s cooling temperature. The indoor fan should operate. Once the indoor fan comes on, allow approximately three minutes for the compressor to start.
2.2 VENTILATION SYSTEM CALIBRATION Manual Fresh Air System (Configuration N). This is the standard ventilation system in the Classic™ heat pump. 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 damper only opens when the indoor fan is operating. Position the screw on the side of the damper hood for the desired air flow.
with the air flow ((CFM) at various static pressures chart. This chart can be found in the Classic Product Data Sheet or the Installation Manual. This CFM is referred to as "C" in the illustration and equation below. Figure 2. Damper Air Path b. "A" is the quantity of outside air expressed as a percentage of "C". For example, if the supply air is 1,220 CFM and 300 CFM of outside air is required, "A" is 25% (300 CFM/1,220 CFM). Measure the temperature of the outside air. Multiply the temperature by "A".
model selected. Voltage must be maintained above minimum specified values listed below. Refer to the unit data plate for ampacity requirements. Table 1. Voltage Limitations Electrical Rating Designations* A C D Nominal Voltage 208/230 208/230 460 Phase 1 3 3 Minimum Voltage 197 197 414 Maximum Voltage 253 253 506 * Letters refer to model number code designations. 3.1 ELECTRICAL Classic heat pumps and air conditioners are built in a wide variety of configurations and options.
Drains 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 Classic™ Heat Pump, causing discoloration of the side panels. If discoloration is noted, service the drains. If a commercial drain solvent is used, flush out the drain pan and system with plenty of fresh water to prevent corrosion.
it removes foreign particulate matter, e.g. dirt, scale, solder particles from the refrigerant to protect the compressor and other components in the refrigerant system with small openings or close tolerances. Second, it absorbs any moisture in the refrigerant with desiccant granules. F. High Pressure Switch and Loss of Charge Switch. These switches render the compressor and outdoor fan motor inoperative whenever the limits of the high or loss of charge switches are exceeded.
The second type of switch is a one time limit switch. If it senses a temperature of 300ºF, power is turned off to the elements. This switch does NOT reset when the temperature drops and must be replaced when it activates. The number and location of both switches is determined by the power supply and the kW of the heaters. M. Ventilation Blower Fan Speed Control. Factory setting for the indoor blower speed is full speed.
fan always starts after the compressor, and it will cycle frequently during normal operation at low outdoor conditions. Q. Compressor Time Delay. The time delay module (delay on make) prevents the compressor from restarting immediately after interruption of power. The delay interval, which is adjustable from .2 to 8 minutes, protects the compressor by allowing internal refrigerant pressures to equalize. The time delay does not effect the electric heat circuit. 6.
Cooling Mechanical Checks Flow Chart Unit Running? High Head Pressure Dirty Outdoor Filter Inoperative Outdoor Fan Overcharge Recirculation of Outdoor Air Non-condensibles Higher than Ambient Air Entering Outdoor Coil Wrong Outdoor Fan Rotation YES Pressure Problems? Low Head Pressure Low on Charge Low Ambient Temperature Inoperative Compressor Valves Outdoor Check Valve Closed Restricted Indoor Metering Device Restricted Filter Drier Reversing Valve Failure NO Low Suction Pressure Dirty Filters Dirty In
Heating Mechanical Checks Flow Chart Unit Running? High Head Pressure Dirty Filters Dirty Indoor Coil Inoperative Indoor Blower Overcharge Inadequate Indoor Air Flow Non-condensibles Wrong Indoor Blower Rotation Inadequate Ducts YES Pressure Problems? Low Head Pressure Low on Charge Low Indoor Temperature Closed Indoor Check Valve Inoperative Compressor Valves Restricted Outdoor Metering Device Restricted Filter Drier Reversing Valve Failure NO Low Suction Pressure Dirty Outdoor Coil Inadequate Air Flow
Subcooling Calculation 1. Measure the liquid pressure at the liquid line service valve. 2. Convert the liquid line pressure to saturated temperature. See tables below. 3. Measure the liquid line temperature at the liquid line service valve. 4. Compare the liquid line temperature to the saturated temperature. 5. The difference between saturated temperature and liquid line temperature is the subcooling. Subcooling normal range 12° to 20°. Superheat Calculation 1.
Troubleshooting Chart WARNING DISCONNECT ALL POWER TO UNIT BEFORE SERVICING. CONTACTOR MAY BREAK ONLY ONE SIDE. FAILURE TO SHUT OFF POWER CAN CAUSE ELECTRICAL SHOCK RESULTING IN PERSONAL INJURY OR DEATH. Problem/Symptom Unit will not run. Likely Cause(s) 1. Power off or loose electrical connection. 2. Thermostat out of calibration Correction 1. Check for correct voltage at unit disconnect. Check for correct voltage at contactor in unit. 2. Reset. - set too high. Outdoor fan runs, compressor doesn’t.
Troubleshooting Chart (cont’d) Problem/Symptom Low head - high vapor pressures. Low vapor - cool compressor - iced indoor coil. Likely Cause(s) 1. Flow check piston size too large. 2. Defective compressor valves. 3. Incorrect capillary tubes. 1. Low indoor air flow. 2. Operating below 55°F outdoors. 3. Moisture in system. High vapor pressure. Fluctuating head and vapor pressures.. 1. 2. 1. 2. Excessive load. Defective compressor. TXV hunting. Air or non-condensibles in system. Correction 1.
Problem/Symptom High head pressure. Compressor Overheating (cont’d) Correction Likely Cause(s) 1. Overcharge. 1. Check system charge. 2. Dirty heat pump coil. 2. Clean coil. 3. Faulty or wrong size heat pump 3. Replace fan motor. fan motor. 4. Faulty outdoor blower. 5. Recirculation of air. 6. Additional heat source. 7. Non-condensibles 4. Replace blower. Replace with correct rotation motor. 5. Correct installation. 6. Check for recirculating from other equipment. 7.
Problem/Symptom No voltage on line side of compressor contactor. Improper voltage. Moisture. Electrical (cont’d) Likely Cause(s) 1. Blown fuses or tripped circuit breaker. 2. Improper wiring. 1. High voltage. 2. Low voltage. 3. Single phasing (3 phase). Contamination 1. Poor evacuation on installation or Correction 1. Check for short in wiring or unit. 2. Recheck wiring diagram. 1. Power supply problem. 2. Power supply problem. Wiring undersized. Loose connections. 3. Check incoming power and fusing.
Problem/Symptom Poor system control using capillary tubes. Flooding (cont’d) Likely Cause(s) 1. Overcharge. 2. High head pressures. Correction 1. Check system charge. 2. Dirty heat pump. Restricted air flow. Recirculation of air. 3. Adjust air flow to 400 CFM/Ton. High superheat, low suction pressure. 3. Evaporator air flow too low. Thermostatic Expansion Valves 1. Moisture freezing and blocking 1. Recover charge, install filter drier, evacuate system, recharge. valve. 2.
Problem/Symptom Compressor flood back upon start-up. Superheat is low to normal with low suction pressure. Thermostatic Expansion Valves (cont’d) Correction Likely Cause(s) 1. Any of the causes listed under 1. Any of the solutions listed under symptoms of problem 2. 1. Unequal evaporator circuit loading. 2. Low load or air flow entering evaporator coil. solutions of problem 2. 1. Ensure air flow is equally distributed through evaporator. Ensure proper piston. Check for blocked distributor tubes. 2.
7.1 PROCEDURE FOR FILING A WARRANTY CLAIM 156 Seedling Drive • Cordele, GA 31015 • P.O.
8.1 WARRANTY If any part of your Marvair® Air Conditioner, Heat Pump or Unit Ventilator fails because of a manufacturing defect within fifteen months from the date of original shipment from Marvair or within twelve months from the date of original start-up, whichever is the earlier date, Marvair will furnish without charge, EXW Cordele, Georgia, the required replacement part. Any transportation, related service labor, diagnosis calls, filter, driers, and refrigerant are not included.
9.
HVPA24HP HVPA30HP HVPA36HP HVPA42HP HVPA49HP Contactor, Compressor, 30 Amp PARTS HPA 50020 50020 50020 50020 n/a n/a Contactor, Compressor, 40 Amp HPA n/a n/a n/a n/a 50030 50030 Contactor, Compressor, 30 Amp HPC/HPD 50040 50040 50040 50040 50040 50040 92030 92030 92030 92030 92030 92030 Standard 50419 50419 50419 50419 50419 50419 B-Damper6 50420 50420 50420 50420 50420 50420 Actuator, Motor, B-Damper 40107 40107 40107 40107 40107 40107 Lockout Relay
Classic™ Heat Pump Parts List - Models HVPSA PART Compressor, Scroll Capacitor, Scroll Compressor ufd/volts Compressor Plug/Cord, 80” Long Plug, Unloader Solenoid Comfort Alert Comfort Alert Sound Blanket, Compressor Indoor Coil Thermal Expansion/Check Valve Distributor Assembly Coil, Evaporator, Reheat (G Option4) Valve, 3-Way Diverting (G Option4) Coil, Solenoid Valve (G Option4) Outdoor Coil Distributor, Outdoor, Heating Orifice, Outdoor, Heating Indoor Motor, Double Shafted, 240 Volt, ECM Blower, L.H.
PART Relay, Fan Blower Control (BTR) Relay, B-Damper Actuator, Motor, B-Damper Lockout Relay (LOR) Clip for Low Vibration Relay, Defrost (DFR) Relay, Heat/Cool, DPDT, 24 Volt Relay, S-Circuit (SR) Relay, Outdoor Fan Motor (OFR) Relay, Heat/Blower (HBR) Sensor, Open 56° F, Close 28° F Resistor, 4.
