Frequently Asked Questions

Maintenance Questions

The motors are sealed and lubrication is not required.

Clean the outside (condenser) coil at least once a year. Gently blow out any debris, which may have collected on the coil, and straighten any fins that may be bent. Since the A/C fan pulls air in through the back of the coil and exhausts it from the sides of the shroud, an obstruction of this airflow will directly affect the performance of the unit.

You may also wash this coil with water if you choose to do so, but DO NOT use a pressure washer. Please remember to disconnect ALL power to the vehicle/air conditioner first.

No. Your Coleman®-Mach® air conditioner is a closed and sealed system and ideally should never require refrigerant recharging. Should you suspect that you have a low refrigerant charge, have the unit evaluated by a qualified service technician.

At RV Products, we have built more than five million RV air conditioners. A great many of them have never required service. However, as with any mechanical device, problems sometimes occur which require service or repairs. This type of service should always be performed by qualified service personnel. Visit our service center and dealer locator.

Retrieve the complete air conditioner model (if you are unsure how to locate the unit model number, visit our Where's My Model Number page). This link allows you to see where the rating plate sticker is located.

Once you have the model number, go to our Document Library, key the model number into the search engine on our Literature and Technical Documents page. You will find a large selection of information available for your air conditioner.

Electrical Questions

Proper operating voltage is 115 VAC/60Hz. The unit may be run safely between 104 volts and 125 volts. Do not operate the air conditioner outside of these parameters, as serious component damage may result.

Air conditioners are designed under specific operating conditions reflecting average use. The specification charts listed (data tag) with each model reflect that model's power consumption at these design temperatures only. Design temperatures for most Coleman®-Mach® RV air conditioners are 95° F. outdoor temperature, 80° F. indoor temperature and 50% relative humidity.

We are aware that the conditions under which our air conditioners might be operating may vary considerably from these design parameters. We do not size generators. However, to access information on sizing the units or amp draws, access our Document Library. In the Document Library, type your model number in the search engine and locate the data sheet.

To calculate the max potential startup: Find the running amp draw for your system and multiply it by 2.5. With this information, your generator manufacturer should be able to assist you in sizing a generator suitable for your application.

This is a very broad subject with many possible answers. Some of the most common include:

  • The supply voltage may be too low (see Question 2 in this section).
  • Too many electrical loads on the vehicle’s 30-amp power supply such as refrigerators, converters, coffee pots, microwaves, electric water heaters, etc. will cause a voltage drop.
  • Long extension cords. For assistance in proper sizing of power cords, consult with your RV dealer or service center.
  • Airflow through the outdoor coil (condenser coil) may be obstructed by debris, or the cooling fins may be bent.

If you have eliminated the problems listed above, you may have a more serious issue that would require evaluation by a trained technician.

Light gauge and/or long extension cords tend to cause significant voltage drops to the vehicle/air conditioner. If used, the extension cord should be sized to maintain proper voltage at full load conditions. Serious component damage may occur if the air conditioner is operated under low voltage conditions (see Question 1 in this section). Neither 115-volt “cheater” plugs or 15-amp outlets are recommended.


No. Refrigerant will not become old or wear out. It is intended to last the lifetime of the unit.

Unfortunately, there is not an easy answer to this question. The supply air temperature will vary somewhat proportionally with the temperature of the air being pulled through the return air grille(s) of the air conditioner. Additionally, the outdoor air temperature, humidity, air volume and even proper air conditioning maintenance all have an effect on the air conditioner supply air temperature.

An ideal cooling system should give you an output temperature range of 16-22 degrees lower than the temperature taken in at the filter. Humidity is a significant determining factor in this temperature difference.

You can test the temperature difference by taking a reading at your filter and the first register where air is leaving the system. Please use the same thermometer at each location.

To answer this question, you must understand; air conditioner capacities are rated primarily by their ability to transfer heat from the inside of your vehicle to the outside air. Your air conditioner may freeze up if it fails to pick up or transfer heat for any of the following reasons:

  • Indoor and outdoor temperatures may be too cold (lack of heat)./li>
  • Evaporator air recirculation is possible due to poor or improper installation.
  • Airflow obstructions:
    • Dirty filters. Filters should be cleaned regularly.
    • Supply air louvers may be shut off.
    • Inadequate or damaged ducting (if so equipped).
    • Dirty or plugged cooling (evaporator) coils.
  • Low Fan Speeds (motor that is not pulling enough amps or airflow).
  • Improper Operation: Setting the temperature on the thermostat so low the compressor does not cycle off and on. Running the compressor and low speed fan together may cause “freeze-up” conditions to accelerate.
  • Electrical problems, faulty thermostat, inoperative freeze thermistor.

Heating Questions

The Coleman-Mach heat pump is an effective heat source, as long as outdoor temperatures are above 45°F. Below 45°F, there is not enough heat outside for the system to absorb, and efficiency drops. With a lack of heat, you will run into a freeze up situation that will shut down your compressor, but leave the indoor blower running. We recommend that, if you know your outdoor temperatures are going to be below 45°F, simply heat the application with the LP furnace until the conditions are more ideal for the heat pump.

When your thermostat is in the “Electric Heat” mode, if the set temperature is five or more degrees above what it shows as the room temperature; the thermostat will consider this too much of a load for an electric heat source and bring in the furnace to assist. The furnace will continue to run in this case, until the thermostat is satisfied. When the room temperature starts to drop again, the thermostat will try to proceed as normal, with just the electric heat (unless the difference between set point and room temperature reaches five degrees again).

PLEASE NOTE: Some of our thermostats will not run your electric heat and gas heat simultaneously. They will shut down the electric heat in order to bring in the gas heat.

Multiple consecutive calls for the furnace in the “Electric Heat” mode, can cause the thermostat to lock out the electric heat function for approximately two hours, triggering the furnace only when it needs heat. Download information on the Lockout function of the thermostat.

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