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Dometic RV Air Conditioners
FreshJet, Penguin II and Brisk II: models, specs, thermostat codes, power and parts. Dometic's lineup has changed in the last few years, so the unit on your roof may no longer be sold. Here's what's current, what replaced what, and how to keep an older unit running.
QUICK ANSWER
Dometic's current US rooftop line is the FreshJet 5 Series (13,500 BTU, 15,000 BTU and High Efficiency), 10.5 inches tall with R32 refrigerant. The Penguin II, Brisk II and Blizzard NXT no longer appear in Dometic's US listing, but Dometic says the FreshJet 15K is backward compatible with Penguin II models, and parts for older units are still sold. Thermostat codes E1–E9 are explained below.
WHICH DOMETIC DO YOU HAVE?
Dometic rooftop AC model guide
Model
BTU
Notes
FreshJet 5 15K (FJX5557M)
15,000
12.66–19.73 A, built-in hard start, 14.17 in cutout, about 95 lb, cool-only or heat pump
FreshJet 5 13.5K (FJX5457M)
13,500
Low profile, R32
FreshJet 5 High Efficiency
About 11,000
8.56–13.90 A, 10.5 in tall
Penguin II
13,500 / 15,000
Low profile; heat pump versions (641815, 641816 and others); no longer in the US listing
Brisk II (B57915)
13,500
13 7/8 in tall, 77 lb, cool only; listed out of stock
Blizzard NXT
13,500 / 15,000
Older line; still covered in Dometic ceiling assembly manuals
From dometic.com and Dometic installation manuals, checked October 2026. Dometic's current rooftop manual also lists model numbers such as 457915, 459516, 640315, 640316C and FJX3473M; the 13,500 BTU and 15,000 BTU versions share the same 14 x 14 in roof opening.
REPLACING A UNIT
Replacing a Penguin II or older Dometic
What carries over
Dometic says the FreshJet 5 15K is "backwards compatible with Penguin II models"
Dometic specifies a 14.3 x 14.3 in roof opening (plus or minus 0.1 in) and 1.5 to 6 in from roof to ceiling
Owners commonly match Penguin II 640316 to FreshJet FJX5557M, and heat pump models to FJX5557MHP
What to check first
Ducted or non-ducted: non-ducted units need a ceiling air distribution box; ducted units need a ducted ceiling kit and return grille
Thermostat: owners report older units use an RJ11 thermostat cable and FreshJet uses RJ45, so heat pump swaps may need an adapter
Roof pitch: some low-profile models allow only 8° of tilt
THERMOSTAT CODES
Dometic thermostat error codes (CCC2 and single-zone)
Code
What it means
What still works
E1
Lost communication with the AC control board(s)
System shuts down
E2
Indoor temperature sensor open or out of range
Fan only
E3
Indoor temperature sensor shorted
Fan only
E4
Outdoor temperature sensor open (select models)
Everything but the heat pump
E5
Freeze sensor open or out of range
Heat sources; AC locked out
E7
No 120V AC power reaching the control boards
System shuts down
E8
Heat pump and heat strip DIP switches both on in one zone
Setup error
E9
Dehumidify DIP switch on with heat pump or heat strip
Setup error
From Dometic's Comfort Control Center 2 (CCC2) and single-zone LCD thermostat manuals. The single-zone thermostat uses codes E1–E5 with the same meanings. Both thermostats delay compressor starts by about 2 minutes, and the CCC2 staggers two ACs by 20–30 seconds.
E1 is the most common call: check 12V power at the thermostat and the thermostat cable before replacing a board. E7 points to the 120V side: breaker, shore power or generator.
POWER
Amps, generators and soft starts
What Dometic specifies
Compressor running current 10.5–13.3 A; starting (locked-rotor) current 52–73 A
A 20 A time-delay breaker and 12 AWG copper wire for runs up to 24 ft
Generator: at least 3.5 kW for one AC, 5 kW for two; generators lose power at altitude
Making it start easier
The FreshJet 5 15K has a built-in hard start
An aftermarket soft start (such as Micro-Air EasyStart) can cut starting current by 60–75%, which may let a 2,000 W generator or 30 A service start one AC
Wait at least 2 minutes before restarting a compressor
MAINTENANCE
Four things Dometic tells owners to do
1
Clean the filter
Clean the return-air filter at least every two weeks of use, and never run the AC without it.
2
Keep vents open
Keep at least two ceiling vents open in cool mode to keep the coil from freezing.
3
Thaw ice on fan
If the coil ices up, run Fan Only until it clears, then set the thermostat a little warmer.
4
Leave the motor alone
Dometic's blower motor is factory-lubricated and needs no oiling.
HEAT PUMPS
Dometic heat pump models
How the CCC2 handles cold weather
Below 30°F outside, the CCC2 switches to the furnace or heat strip, and goes back to the heat pump above 35°F
Between 30°F and 42°F it runs defrost cycles: 4.5 minutes after every 25 minutes of compressor run time
A heat strip is supplemental heat only and doesn't replace your furnace
WHERE TO BUY
Where to buy Dometic AC units and parts
Store
Type
Dometic AC
Good for
Category specialist
FreshJet units, Penguin II and Blizzard NXT parts
Matching parts to your model; free shipping on new rooftop ACs
Manufacturer
Dealer finder, manuals, warranty
Warranty claims; Dometic sells FreshJet through its dealer network
Store details checked October 2026. Dometic RV support: (800) 544-4881. Manuals: Dometic rooftop AC manual · NHTSA recalls (we found no 2020–2026 recalls for Dometic rooftop ACs).
QUESTIONS
Dometic AC FAQ
Is the Dometic Penguin II discontinued?
The Penguin II no longer appears in Dometic's US rooftop AC listing, which now shows only the FreshJet 5 Series. Dometic says the FreshJet 5 15K is backward compatible with Penguin II models, and Penguin II parts are still sold.
What does E1 mean on a Dometic thermostat?
E1 means the thermostat lost communication with the AC control board, and the system shuts down. Check 12V power at the thermostat and the thermostat cable before replacing parts.
What does E7 mean on a Dometic CCC2?
E7 means the control boards aren't getting 120V AC power, so the system shuts down. Check the breaker, shore power and generator.
How many amps does a Dometic RV air conditioner use?
Dometic rates its 13,500 and 15,000 BTU compressors at 10.5–13.3 amps running, with 52–73 amps for a moment at start-up. The FreshJet 5 15K is listed at 12.66–19.73 amps.
What size generator do I need for a Dometic AC?
Dometic recommends at least a 3.5 kW generator for one rooftop AC and 5 kW for two. A soft start can let a smaller generator start a single unit.
How often should I clean a Dometic AC filter?
Dometic says to clean the return-air filter at least every two weeks of operation, and never to run the AC without the filter in place.
NEED A DOMETIC AC PART?
Start with your model number
RV AC Guys carries Dometic FreshJet units and Dometic AC parts, including for older Penguin II and Blizzard NXT units, and can help you match the right one.