Dometic FreshJet
Official technical documentation and workshop diagnostics for Dometic FreshJet.
Technical Specifications
ElectricalOperating Frequency: 2.4 GHz, Maximum radio frequency power: 20.5 dBm
Gas Or PressureNot applicable
Capacities DimensionsRoof thickness compatibility: > 60 mm to 90 mm; Screw sizes: M6 x 160 mm (for 70 mm – 90 mm roof thickness), M6 x 120 mm (for 60 mm – 70 mm roof thickness); Spacer dimensions: 45 mm, 30 mm, 15 mm
Master Troubleshooting & Diagnostics Matrix
| Error Code / Indicator | Symptom / Meaning | Step-by-Step DIY Fix | Suggested Actions |
|---|---|---|---|
N/A | [Gas / Refrigerant] Faults in refrigerant circuit Possible Cause: Refrigerant circuit leakage or internal component failure | Appliance must be checked and repaired exclusively by the manufacturer, its service agent, or similarly qualified personnel using approved procedures. | Professional Intervention Required |
N/A | [12V DC / 230V AC] Power supply failure during maintenance or work Possible Cause: Power supply connected during servicing | Always disconnect the power supply completely when working on the appliance. | DIY Safe |
N/A | [Mechanical] Damaged supply cord Possible Cause: Normal wear, pinching, or physical damage to the power cable | Must be replaced by the manufacturer, its service agent, or similarly qualified personnel to avoid a hazard. | Professional Intervention Required |
N/A | Roof air conditioner constantly switches itself off. Possible Cause: Icing sensor has tripped. Outer temperature is too low or all air nozzles are closed. | Check ambient temperature limits and ensure air nozzles remain open. | DIY Safe |
N/A | Roof air conditioner constantly switches itself off Possible Cause: Icing sensor has tripped due to outer temperature being too low or all air nozzles are closed | Open air nozzles and ensure ambient temperature is within operating limits. | DIY Safe |
N/A | No cooling capacity (Set to cooling) Possible Cause: The ambient temperature is above 52 °C or below 16 °C. | Ensure ambient temperature is within the designed operating range (16 °C to 52 °C). | DIY Safe |
N/A | No cooling capacity (Temperature set points) Possible Cause: The temperature set is higher than the room temperature. | Select a lower temperature setting on the controller. | DIY Safe |
N/A | No cooling capacity (Sensor or Fan failure) Possible Cause: One of the temperature sensors, vaporiser fan, or condenser fan is defective. | Contact an authorised workshop to test and replace defective sensors or fans. | Professional Intervention Required |
N/A | Low air output Possible Cause: The air intake section is clogged up with leaves and dirt, or the blower is defective. | Remove debris from the ventilation grilles or contact an authorised workshop if the blower is defective. | DIY Check / Tech Fallback |
N/A | Water enters the vehicle Possible Cause: The condensation water drainage openings are clogged up or seals are damaged. | Clean the drainage openings for condensation water or replace damaged seals via an authorised workshop. | DIY Check / Tech Fallback |
N/A | Roof air conditioner does not switch on. Possible Cause: No supply voltage (230 V AC) connected, voltage is too low (under 200 V), voltage converter is defective, temperature sensor is defective, or electrical fuse is too low. | Check power supply, verify incoming voltage is above 200 V, check electrical fuses, and consult an authorised workshop if components are defective. | DIY Check / Tech Fallback |
N/A | Roof air conditioner does not switch on Possible Cause: No 230V supply voltage connected, voltage too low (under 200V), defective voltage converter, defective temperature sensor, or electrical supply fuse too low | Check 230V power supply and electrical fuse ratings; contact authorised workshop for converter or sensor faults. | DIY Check / Tech Fallback |
N/A | Roof air conditioner does not switch off. Possible Cause: One of the temperature sensors is defective or electrical fuse rating is improper. | Contact an authorised workshop to check sensors and power supply configuration. | Professional Intervention Required |
N/A | Roof air conditioner does not switch off Possible Cause: One of the temperature sensors is defective or electrical supply fuse is rated too low | Contact an authorised workshop to check and replace the temperature sensor. | Professional Intervention Required |
N/A | Appliance does not start Possible Cause: Power supply disconnected or incorrect voltage | Check power supply, voltage, and fuses. Ensure data plate specifications match power source. | DIY Safe |
N/A | Insufficient cooling or heating performance Possible Cause: Refrigerant circuit fault or blocked airflow | Check for refrigerant leaks and ensure air outlets/inlets are unobstructed. | DIY Safe |
N/A | No cooling capacity Possible Cause: Unit not set to cooling, ambient temperature above 52 °C or below 16 °C, temperature set higher than room temperature, or defective temperature sensor / damaged fans | Set unit to cooling mode, adjust target temperature below room temperature, operate only within 0 °C to +52 °C ambient limits, or contact an authorised workshop for sensor/fan replacement. | DIY Check / Tech Fallback |
N/A | No cooling capacity Possible Cause: The roof air conditioner is not set to cooling, ambient temperature above 52 °C or below 16 °C, temperature set higher than room temperature, defective temperature sensor, damaged vaporiser or condenser fan | Set the roof air conditioner to cooling, select a lower temperature, or contact an authorised workshop for sensor/fan replacement. | DIY Check / Tech Fallback |
N/A | Low air output Possible Cause: The air intake section is clogged up, or the blower is defective | Remove leaves and other dirt from the ventilation grilles, or contact an authorised workshop. | DIY Check / Tech Fallback |
N/A | Water enters the vehicle Possible Cause: The condensation water drainage openings are clogged up, or seals are damaged | Clean the drainage openings for condensation water, or contact an authorised workshop to replace damaged seals. | DIY Check / Tech Fallback |
N/A | Roof air conditioner does not switch on Possible Cause: No supply voltage (230 V) connected, voltage too low (under 200 V), defective voltage converter, defective temperature sensor, or electrical fuse of the power supply is too low | Check the power supply and electrical fuse, or contact an authorised workshop. | DIY Check / Tech Fallback |
N/A | Roof air conditioner does not switch off Possible Cause: The electrical fuse of the power supply is too low | Check the electrical fuse of the power supply. | DIY Safe |
N/A | Device does not switch on or respond to commands Possible Cause: Power supply disconnected or incorrect voltage | Check power supply, verify voltage matches data plate, and ensure unit is switched on from standby. | DIY Safe |
N/A | Unit fails to cool or heat properly Possible Cause: Incorrect mode selection, blocked air flow, or refrigerant circuit fault | Check air conditioning mode and fan settings, ensure minimum 50 cm clearance around air outlets, and have qualified personnel check refrigerant circuit if faulty. | DIY Check / Tech Fallback |
N/A | Fan does not start immediately in heating mode Possible Cause: Normal operational delay | No action required; fan automatically starts after 2 minutes on low level and switches to set level after about 5 minutes. | DIY Safe |
Frequently Asked Questions
Q: MY ROOFTOP UNIT HAS THE ELECTRIC HEAT STRIP OPTION (NON-HEAT PUMP ELECTRIC HEAT OPTION), BUT WHEN IT GETS COLDER OUTSIDE IT DOESN’T SEEM TO MAINTAIN THE TEMPERATURE. WHAT SHOULD I DO?
Electric heat strips are designed to take the chill out of the air inside your motorhome, but they are not intended to be the primary heat source for cold weather camping. When outdoor temperatures drop significantly, the heat loss of the motorhome typically exceeds the capacity of a standard electric heat strip.
Q: WHAT ARE THE BENEFITS OF A MOTORHOME AIR CONDITIONER?
An motorhome air conditioner helps maintain a comfortable indoor climate, reduces humidity levels inside the vehicle, and filters out dust and pollen, creating a more pleasant and healthy living space while traveling or camping.
Q: WHAT IS THE IDEAL AIR CONDITIONING TEMPERATURE?
The ideal indoor air conditioning temperature for an motorhome is generally between 70°F and 72°F (21°C to 22°C), balancing comfort and energy efficiency.
Q: WHAT MOTORHOME AC DO I NEED IN WARM LOCATIONS?
For extremely warm locations or larger motorhomes, a high-capacity rooftop air conditioner (such as a 13,500 BTU or 15,000 BTU unit) or a dual AC setup is recommended to adequately cool the space.
Q: HOW DOES MOTORHOME AIR CONDITIONING WORK?
Motorhome air conditioning works on the same principle as a standard home AC unit. It uses a refrigeration cycle involving a compressor, condenser, expansion valve, and evaporator to absorb heat from the interior air and exhaust it outside, while blowing cooled air back into the motorhome.
Q: HOW TO RUN MY MOTORHOME AC WITH A GENERATOR?
To run your motorhome air conditioner with a generator, ensure the generator has sufficient running and starting wattage (surge wattage) to handle the compressor's startup load—typically a minimum of 2,000 to 3,000 watts depending on the AC unit size. Always start the generator and let it stabilize before turning on the air conditioner.
Q: HOW TO RUN MY MOTORHOME AIR CONDITIONER ON THE CAMPSITE?
To run your motorhome air conditioner at a campsite, connect your motorhome to an appropriate power pedestal (usually 30-amp or 50-amp service) matching your motorhomes electrical system requirements. Ensure other high-draw appliances are managed to avoid tripping the campsite breaker.