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Anyone who has built their own camper knows the problem: a good boiler is easy to install — but when it heats, for how long, and whether it drains the battery is often left to chance. The Pundmann boilerCONTROL changes that.

What is the boilerCONTROL?

The boilerCONTROL is a compact control unit developed specifically for mobile hot water and heating systems in campervans, motorhomes and off-grid vehicles. Via four powerful relays it manages up to two electric heating elements as well as an external diesel heater — intelligently, automatically and without constant manual intervention.

It works with 12 V and 24 V on-board systems, is compatible with all common boilers — including third-party models — and can be operated either via a physical button or conveniently from your smartphone over Wi-Fi.

In a nutshell: The boilerCONTROL is the missing brain behind your boiler. It heats when you want it to, switches off automatically once the temperature is reached — and actively protects your battery.

Key features at a glance

Wi-Fi control without an app — Configure directly in your browser, no download, no cloud, no account needed. Works on any smartphone or tablet.

Automatic solar surplus heating — As soon as the battery is full, the boilerCONTROL automatically uses excess PV energy to heat water. No energy is wasted.

Integrated battery guard — The configurable undervoltage protection on Relay 1 shuts down in good time — protecting your LiFePO4 or AGM battery.

4 independent relays — Switch 12 V, 24 V and 230 V heating elements. Plus a free channel for lighting or other loads of your choice.

Advanced settings — what's behind them?

The browser interface is more than just on/off. The gear icon gives you access to advanced settings that make the boilerCONTROL truly powerful.

Target temperature and safety cut-off

Set exactly what temperature you want the water heated to — from 50 °C to 80 °C. Once the target is reached, the system switches off automatically. As an additional safety net, you define a maximum heating time between 10 and 180 minutes.

Single heat-up — the energy-saving mode

In this mode the boilerCONTROL heats the water exactly once to the target temperature and then switches off permanently. No reheating, no unnecessary consumption. Perfect for the evening: heat once — done.

Undervoltage protection with visual feedback

Set a voltage threshold. If the on-board voltage drops below it, Relay 1 switches off automatically. At the same time the first physical button flashes exactly 8 times every 90 seconds — a clear warning signal.

Using solar surplus for heating

This is the feature that excites off-grid campers: instead of wasting excess photovoltaic energy, the boilerCONTROL uses it specifically to heat water — fully automatically.

Via the AUX input (0–24 V), an external battery computer — such as the Victron BMV 712 — can send a signal as soon as the batteries are fully charged. The boilerCONTROL detects this signal and automatically activates the selected heating elements.

How to set up PV mode:

  1. Wire it up — Connect the relay output of your battery computer to the AUX input of the boilerCONTROL (0–24 V, max. 28 V).
  2. Activate the function — In advanced settings: "Boiler heating with battery surplus" → click "Activate function".
  3. Assign relays — Select which heating elements should activate — multiple at the same time is possible.
  4. Done — From now on the sun heats your boiler automatically whenever the batteries are full.

Wi-Fi access in 4 steps

No app, no cloud — everything runs directly in your browser:

  1. Switch on — The boilerCONTROL automatically opens its own Wi-Fi access point.
  2. Connect — Connect your smartphone. Default password: 12345678
  3. Open browser — Type boilercontrol.local — the control interface appears immediately.
  4. Set up — Change password, set temperature, name relays — done.

Security tip: Change the default Wi-Fi password after initial setup — especially on campsites with shared networks.

Space heater and Relay 4 — the bonus

Relay 3 is designed to control an external space heater — such as an Autoterm or any other model with an external control input. The fourth relay is a free universal switch: perfect for an awning light, a pump or other 12 V/24 V loads.

The boilerCONTROL is available from PUNDMANN as an authorised distributor. Personal advice at m.herbst@pundmann.de or directly in the shop at www.pundmann.de.