Frequently Asked Questions

The control box is not part of the air conditioner, so you cannot determine what replacement control box you need from the AC model number alone. Instead, what you need is either the part number of the original control box or which thermostat you are using to determine what replacement control box will work in your system.

On our YouTube channel Coleman-Mach has a helpful video on Finding Essential Part Numbers on Coleman-Mach RV Components including rooftop unit model numbers, control box/ducted ceiling unit, non-ducted ceiling assembly, wall thermostats, and motors.

Though the VIN carries much information with the coach manufacturer, as the air conditioning manufacturer we are not made aware of what coach any particular serial number of our AC is installed on. Instead, we need the model or serial number of the AC unit itself in order to provide the appropriate assistance.

On our YouTube channel Coleman-Mach has a helpful video on Finding Essential Part Numbers on Coleman-Mach RV Components including rooftop unit model numbers, control box/ducted ceiling unit, non-ducted ceiling assembly, wall thermostats, and motors.

If all you have is a VIN number, please contact the manufacturer of your RV to inquire about the AC unit numbers installed on their RV models.

There are many thermostats that are interchangeable with many roof top AC units to give RV owners the variety and flexibility to find a model that best suits their RV lifestyle. To know which thermostats are compatible with your AC unit you need the “RVP” number off the back of your current thermostat.

On our YouTube channel Coleman-Mach has a helpful video on Finding Essential Part Numbers on Coleman-Mach RV Components including rooftop unit model numbers, control box/ducted ceiling unit, non-ducted ceiling assembly, wall thermostats, and motors.

If you remove the thermostat from the wall completely (you can leave wires connected), you should find a sticker on the back of the mounting plate for the thermostat that will have an “RVP” number. There will also be a part number listed, but we would need the “RVP” number to assist.

On our YouTube channel Coleman-Mach has a helpful video on Finding Essential Part Numbers on Coleman-Mach RV Components including rooftop unit model numbers, control box/ducted ceiling unit, non-ducted ceiling assembly, wall thermostats, and motors.

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 Coleman-Mach, we have built more than 8 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.

The filters used are determined by what ceiling assembly you have, not by the AC model number. As there are many ceiling assemblies that will work with different models, the model of the roof top unit will not be enough information to determine which filters you need. Instead, figure out what kind of ceiling assembly you have to determine what filters you need.

On our YouTube channel Coleman-Mach has a helpful video on Finding Essential Part Numbers on Coleman-Mach RV Components including rooftop unit model numbers, control box/ducted ceiling unit, non-ducted ceiling assembly, wall thermostats, and motors.

The warranty is 2 years from the date of purchase. This will cover any product or manufacturer defects. It does not require registration. You would simply keep your proof of original purchase date for possible future warranty issues.

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. Visit our Service Center and Dealer Locator.

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.

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.

Though most of our roof top units are heat strip ready, you may have to change out controls to add the extra function. If you are controlling this with a wall thermostat, you may also need to run an extra wire between it and the control box for this extra function as well.

On our YouTube channel Coleman-Mach has a helpful video on Installing an Electric Heat Element in a Coleman-Mach Air Conditioner that shows the entire process with useful tips from our AC expert. Coleman-Mach recommends a licensed, trained technician completes this installation. RV owners can find the service center closest to their location using the Service Center and Dealer Locator.

Find additional product information on the Coleman-Mach AirSpace Electric Heat Element HERE, part of Coleman-Mach’s Climate Control Accessories.

A heat strip is an optional add-on for RV air conditioners. Though most Coleman-Mach rooftop ACs are heat strip ready, none come automatically equipped with one. However, heat strips can easily be fitted into existing compatible AC units by a trained RV technician.

Find the closest authorized RV technician to your location on the Service Center and Dealer Locator.

Find additional product information on the Coleman-Mach AirSpace Electric Heat Element HERE, part of Coleman-Mach’s Climate Control Accessories.

Though all models of RV air conditioners have nuanced differences in design, there are core parts found in every single one including evaporator coils, refrigerants, a compressor, and condenser coils because they’re integral in the process of cooling air.

For RV air conditioners, the unit pulls hot air from the interior of your coach through the intake vent and forces the heated air over the evaporator coils that are filled with refrigerants. The refrigerants, which are cooling chemicals in a liquid form, absorb the heat from the air and this energy transfer has two effects. First, the air is cooled; and second, the refrigerant is converted into a gaseous stage. That cooled air is then pushed back into the RV interior to drop the ambient temperature.

The gaseous refrigerant needs to be converted back into a liquid form in order to continue the cooling cycle, so it moves to the compressor. The compressor puts an incredible amount of pressure on the refrigerant forcing the chemical to release heat as it converts back into a liquid. The heat is then dispersed from the RV to the outside world via the condenser coils (located on the RV rooftop) and the liquid refrigerant is moved back into the evaporator coils to restart the AC process.

Voltage – Measured in volts (V), voltage is the amount of pressure in an electric circuit coming from the power source that pushes the electric current through the conducting loop. You need to know about AC voltage because RV air conditioners operate in a very specific voltage range and running a unit outside that range is unsafe and can cause serious damage to your AC.

Amperage – Amperage is the strength of a current of electricity expressed as amps. For RV ACs it measures the unit’s power consumption so RV owners know what power draw they can expect when using the air conditioner (or heating element if present) so they can properly account for overall energy usage in their coach.

BTUs – A BTU is a measure of heat, specifically the amount of heat required to raise the temperature of one pound of water by 1° Fahrenheit. When it comes to your RV air conditioner, BTUs are used to measure the amount of heat that the unit can drain from an interior space in the span of an hour. Therefore, the higher the BTU rating, the greater the AC’s cooling power.

As the name implies, the difference between these two common types of RV air conditioners is the use of or lack of ductwork. Ducted units use ductwork built into the RV to distribute cooled air to different zones in the vehicle. Non-ducted AC units, on the other hand, blow directly into the interior spaces and do not use built-in ductwork.

While an air conditioner’s main purpose is to cool air, modern designs have made this appliance multifunctional with the addition of a heat pump. This heating element is able to pull heat in from the ambient environment and transfer its warmth to the coach’s interior. A heat pump is not as powerful as your RV furnace for extreme weather conditions, rather it’s ideal for chillier conditions in the spring, summer, and fall when the full, propane-consuming force of the furnace is not needed.

While both a heat pump and a heat strip are components that create heat within an AC unit, they’re not interchangeable. An air conditioner with a heat pump is capable of reversing its cycle to draw heat from the environment and transfer it into the RV interior. As such, an AC unit with a heat pump is built with different components in the refrigerant circuit to reverse the flow of refrigerant. Heat pumps are built into the unit at the time of manufacturing, and they are not something that can be added on at a later date.

A heat strip, on the other hand, can be retrofitted into existing air conditioners that do not have a heat pump. Most Coleman-Mach AC units are heat strip ready, giving RV owners the option of adding it in after purchase. A heat strip works off the AC electric system gently warming the interior. Find additional product information on our AirSpace Electric Heat Element HERE, part of Coleman-Mach’s Climate Control Accessories.