Searching for a Truma iNet Box alternative is no longer a niche topic. More and more motorhome owners run into the same problem: they want to control their Truma Combi from a smartphone — but the official solution from Truma is either sold out, technically dated, or simply not what they had hoped for.
Truma has discontinued production of the classic iNet Box. The successor, iNet X, is aimed at newer vehicles and is not compatible everywhere. And the DIY solutions circulating in camper forums are technically fascinating — but not for everyone.
In this article we show you every relevant alternative to the Truma iNet Box, explain honestly what they can and cannot do — and help you make the right decision for your vehicle and your expectations.
Why the Truma iNet Box is no longer a good choice
A quick recap so it is clear what we are talking about.
The original Truma iNet Box was the first official way to control a Truma Combi from a smartphone. It connects to the CP Plus control panel and passes on commands — in theory an elegant solution.
In practice there are several problems:
- Dated technology: The iNet Box uses 2G/GSM for remote control outside the local WiFi. In Switzerland 2G is already fully switched off. In Germany and Austria more shutdowns are following. Anyone travelling internationally has the problem today.
- SIM card required: For remote access over the internet the iNet Box needs an active SIM card — running costs, activation effort, one more dependency.
- No longer produced: Truma no longer makes new iNet Boxes. Used units can still be found, but sometimes at inflated prices — and with no guarantee that the infrastructure behind it keeps working for long.
- No Alexa or Google Home integration: Voice control is not provided for. For many a deciding point.
- Complex setup: App pairing, SIM activation and CP Plus compatibility overwhelm many users.
In short: the iNet Box was usable in its day. Today it is no longer a recommendable investment — neither new nor used.
The alternatives at a glance
There are essentially four ways to control your Truma Combi smartly without the iNet Box. From simple to complex.
Option 1: Truma iNet X system — the official successor
Truma has positioned the iNet X system as the evolution. It combines a new panel (iNet X panel) with a Connect Box and uses modern WiFi instead of 2G.
What it can do: Full control via the Truma Level X app, timer functions, temperature readout. For newer vehicles with a compatible CP Plus, a solid solution.
What it cannot do: The iNet X system is only compatible with certain CP Plus versions. In the VW Grand California, which ships with an older-generation CP Plus, retrofitting is laborious and expensive — often panel and box must be bought together, quickly reaching €250 to €350 plus installation. No Alexa integration, no native smart-home connections. For Grand California owners often disproportionately laborious for what you get.
Option 2: WomoLIN — the open LIN controller
WomoLIN is an open-source project offering a free controller for the LIN bus of Truma devices. The idea: Truma's proprietary communication protocol between the CP Plus and the heater is read out and integrated over MQTT or other standards into your own smart-home infrastructure.
What it can do: A great deal. WomoLIN integrates with Home Assistant, ioBroker, Node-RED and other systems. If your whole motorhome is networked, this gives you a powerful solution.
What it costs: Time. A lot of time. WomoLIN is a tinkerer's project. Setup requires knowledge of Home Assistant, MQTT and network configuration. If you are not familiar with those, you will invest hours, if not days. For technically savvy campers who already run a smart-home setup in the vehicle: an excellent option. For everyone else: not a realistic path.
Option 3: DIY with ESPHome or similar
Various motorhome forums and blogs document in detail how to build your own iNet Box alternative — typically with an ESP32 microcontroller and the ESPHome firmware.
The principle: the ESP32 communicates over the LIN bus with the CP Plus and exposes the heating control via the Home Assistant API or directly over WiFi. Result: full control, Alexa integration possible, no dependency on Truma's infrastructure.
What it can do: Everything WomoLIN can — sometimes more.
What it costs: Even more time. A soldering iron. Basic knowledge of electronics and microcontroller programming. Tolerance for debugging. And the courage to work on your own vehicle's electronics. For makers and tech enthusiasts an exciting project. For the large majority of motorhome owners unrealistic — and on a vehicle like the Grand California, which may still be under warranty, not without risk either.
Option 4: CampMatic — plug-and-play for the Grand California
CampMatic is the only WiFi controller for the Truma Combi developed specifically for the VW Grand California — no tinkering, no installation, no workshop.
The concept is radically different from the alternatives above: not a universal system you somehow connect to the Truma, but a product designed from the start for exactly this vehicle and exactly this heater.
What CampMatic can do:
- Switch the Truma Combi on and off from the app
- Set the temperature and read the actual temperature
- Choose the operating mode (heating, hot water, both)
- Set timers and schedules
- Native Alexa voice control: "Alexa, start the heating at 20 degrees."
- Offline operation over its own WiFi hotspot — no campsite WiFi, no mobile network needed
- The CP Plus control panel stays fully functional
What installation means: CampMatic is plugged in between the existing CP Plus and the Truma Combi. No tools, no intervention in the vehicle electrics. Installation time under ten minutes. The warranty on the Truma Combi remains untouched. No SIM card. No 2G dependency. No tinkering.
→ Learn more about CampMatic — the smart WiFi controller for the Grand California
The direct comparison: all options at a glance
Truma iNet X
- Technology: WiFi (modern)
- Installation: Laborious, workshop sometimes needed
- Cost: €250–350 + installation
- Grand California compatibility: Limited, retrofitting laborious
- Alexa: No
- Target group: Owners of newer vehicles with a current CP Plus
WomoLIN
- Technology: LIN bus over MQTT/Home Assistant
- Installation: Technically complex, several hours
- Cost: Cheap (hardware), expensive (time)
- Grand California compatibility: Possible with effort
- Alexa: Possible via a workaround
- Target group: Tech enthusiasts with a smart-home setup
ESPHome DIY
- Technology: ESP32, ESPHome, Home Assistant
- Installation: Very complex, soldering, programming
- Cost: Very cheap (hardware), very expensive (time + knowledge)
- Grand California compatibility: Possible
- Alexa: Possible via Home Assistant
- Target group: Makers, electronics tinkerers
CampMatic
- Technology: WiFi, modern stack
- Installation: Plug-and-play, under 10 minutes
- Cost: One-off purchase price, no running costs
- Grand California compatibility: Developed specifically for it
- Alexa: Yes, native
- Target group: Grand California owners who just want it to work
Which alternative is right for you?
The honest answer depends on who you are and what you want.
You have a VW Grand California and just want a working solution
CampMatic. Full stop. No other alternative is so directly designed for it. No installation effort, no soldering iron, no workshop appointments. You plug it in, set up the app, done. The heating is smart.
You already run Home Assistant and want to fully network your motorhome
WomoLIN or ESPHome are sensible options. You already have the knowledge and the infrastructure — then your own LIN controller is the most flexible solution. You can build automations, log data and integrate the heater into existing scenes. See also: Truma in Home Assistant over MQTT.
You have a newer vehicle with a current, iNet-ready CP Plus and want the official solution
The Truma iNet X is then the natural choice — even if the price hurts. You get a complete, officially supported solution with app and timer. For vehicles that CampMatic is not designed for, the first serious option.
You want Alexa voice control without a smart-home ecosystem
CampMatic is currently the only solution that offers native Alexa integration for the Truma Combi — without you having to run Home Assistant, ioBroker or similar. All DIY solutions can do this in theory, but not without considerable extra configuration.
What to check before buying
Whichever alternative you choose — one point is decisive: is your CP Plus "iNet ready"?
All solutions that communicate over the LIN bus need a CP Plus labelled "iNet ready" on the device. Older CP Plus units without this note do not support the communication. Check this briefly before ordering — you will find the unit on the inside wall of your motorhome, usually near the bed or the kitchen. In the VW Grand California an iNet-ready CP Plus is fitted as standard — so you are on the safe side.
Conclusion: the iNet Box is yesterday
The original Truma iNet Box is no longer what you should buy — neither used nor new, if you can still find one. The technology is dated, the infrastructure uncertain, and the alternatives are better in almost every respect.
Which Truma iNet Box alternative is right depends on a single factor: how much effort you are willing to invest.
For the majority of Grand California owners who simply want the heating to be controllable by app and Alexa — without tinkering, without installation, without running costs — there is a clear answer: CampMatic.
For anyone who wants to go deeper: WomoLIN and ESPHome are impressive projects that show what is possible if you invest the time. But for everyday life at the campsite — and especially in winter — what counts in the end is that it simply works.
