The situation
A customer has two Dometic Penguin I units (620515.321) and needs to replace one of them. They want to keep using their existing CCC1 5-button thermostat, which runs both air conditioners as a multi-zone system. They asked what they need.
The short answer
Dometic suggests the FreshJet 5 Mechanical, paired with the 3109226.005 control box:
- 13,500 BTU — 9620015924 in white or 9620015930 in black
- 15,000 BTU — 9620015933 in white or 9620015927 in black
- Control box — Dometic CCC Multizone Control Kit 3109226.005
The control box is the part that makes this work. It's the control box built for the 5-button thermostat, and it's what allows both air conditioners to run together on the same multi-zone CCC1.
Why
The FreshJet 5 Mechanical is a cooling-only unit with no control logic of its own. It takes its instructions from an external control box — which is exactly why keeping your existing thermostat is possible. The control box translates between the new air conditioner and the thermostat you already have.
The 3109226.005 is specifically the CCC multizone kit, not CCC2. It works with the original Comfort Control thermostats — the generation that's now out of production — and it will not work with a CCC2 thermostat. Your CCC1 5-button is that original generation, so this is the correct pairing. It's also heat-strip compatible. Note it's a control box only; no thermostat is included, which is the point here since you're keeping yours.
You only need one control box. It goes with the new FreshJet 5. The Penguin I you're keeping already has its own board pre-installed to connect to the thermostat, so nothing changes on that side.
Fitment is not a concern. All rooftop air conditioners use the same roof opening, and every Penguin shares the same low-profile footprint as the FreshJet 5. The FreshJet 5 replaces the Penguin I as readily as it does the Penguin II, along with a range of older Dometic units. No roof modification, no cutting.
Match the BTU rating to the unit you're pulling down. Both capacities are the same platform:
- 13,500 BTU — FJX5457MWHCS / 9620015924 (white), FJX5457MBKCS / 9620015930 (black)
- 15,000 BTU — FJX5557MWHCS / 9620015933 (white), FJX5557MBKCS / 9620015927 (black)
What you gain over the unit coming off the roof: a 10.5" low-profile height, built-in hard start (meaningful on 30-amp service or generator power), a reinforced steel base, up to 9dB less cabin noise, and a pre-installed roof compression gasket — no additional sealant or separate gasket needed. It installs ducted or non-ducted.
What to do
- Match the BTU rating to the Penguin I you're replacing, and pick white or black.
- Order the 3109226.005 control kit with the air conditioner. Without it, the new unit won't speak to your CCC1 thermostat. One kit is all you need — it's for the FreshJet 5 only.
- Program the thermostat after installation. Turn the thermostat off, hold down the Mode and Zone buttons, and turn it back on while still holding both. When FF appears, release — the thermostat is now programmed to your system.
- Inspect on delivery. These ship freight, and freight items may not be eligible for standard return processing. Note any damage on the delivery receipt before you sign.
- Have a qualified RV technician do the install — rooftop mounting, weather sealing, 120V AC wiring, and thermostat integration.
Still not sure?
Send us the model and serial off both of your Penguin I units and a photo of your thermostat, and we'll confirm the right capacity and control kit before you order. Ask us here.