Embedded Electronic Designs

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FridgeAir — Smart Fridge Fan Controller
from £64.95

PRE-ORDER — Ships within 2 weeks

Does your motorhome, caravan or campervan fridge struggle in hot weather?

Fridges work hard in summer — and without proper airflow the fridge becomes inefficient.

FridgeAir fixes that.

It continuously monitors the temperature difference between the top and bottom of the cavity and chimney behind the fridge. When the top starts rising faster than the bottom — a reliable early warning that natural airflow is no longer keeping up — FridgeAir automatically starts circulating air before temperatures climb high enough to affect cooling performance.

Quiet when cool. Powerful when hot. You’ll never think about it again.

No app. No Bluetooth. No setup. Just plug it in and it works.

What FridgeAir does

  • Smart delta-driven cooling — unlike traditional thermostatic controllers, FridgeAir reacts to temperature difference, not just temperature, if the top of the cavity starts running noticeably hotter than the bottom, FridgeAir brings the bottom fan in to help circulate air, even before the bottom sensor itself has warmed up.

  • Continuously monitors top and bottom temperatures with precision digital sensors.

  • Variable fan speed — ramps up with temperature, very quiet when cool.

  • Protects your leisure battery — fans cut automatically if voltage drops too low for a sustained period, then restart when charging resumes.

  • Single-sensor mode — works with just one sensor and one fan. FridgeAir automatically switches to a tuned single-fan profile so performance stays strong even when dual-sensor/fan routing isn’t practical.

  • Green LED heartbeat confirms the unit is alive and working.

  • Double-flash warning when the leisure battery voltage is marginal — the unit hibernates until the battery recovers.

  • Boot self-test — both fans run briefly at startup so you know everything is working.

  • While idle and monitoring, FridgeAir draws only ~65µA (~0.002Ah per day), helping preserve your leisure battery.

  • PCB protected with MG Chemicals 419D acrylic conformal coating for moisture and vibration resistance.

Colour-coded and clearly labelled — wiring takes minutes

  • A — 12V DC power input

  • B — Top sensor (RED heat shrink)

  • C — Bottom sensor (BLUE heat shrink)

  • D — Top fan output

  • E — Bottom fan output

What’s in the box

Controller only option

  • FridgeAir controller in carbon-fibre PLA enclosure

  • 2 × DS18B20 temperature sensors (red = top, blue = bottom)

  • 2 × sensor mounting clips

  • 2 × cable ties

  • Quick Start Guide

Complete kit adds

  • 2 × 12V DC 120×120 mm fans with mounting hardware

  • 2m red/black 18AWG silicone cable

  • 2 × lever-nut splice connectors

Technical

  • Protected input — onboard self-resetting polyfuse (3.5A hold / 6A trip) and reverse polarity protection safeguard both the unit and your vehicle wiring from wiring faults and transient events.

  • Supply: 12V DC (leisure battery).

  • Fan output: 12V PWM, dual channel, variable speed.

  • Top fan triggers above 45 °C, full speed at 65 °C.

  • Bottom fan triggers above 40 °C, full speed at 65 °C.

  • Separate fan profiles optimise airflow direction and minimise unnecessary fan operation.

  • Smart delta-latchautomatically runs the bottom fan whenever the top sensor is above 36°C and the temperature difference between top and bottom reaches 8°C, ensuring cold-air circulation even before the bottom temperature rises on its own. Once running, it stays engaged until the gap is acceptable.

  • Leisure battery warning below 12.3V, protection cuts in below 12.0V sustained, auto-recovers above 12.4V.

  • Flexible fan outputs — each channel can drive two fans in parallel (max 0.5 A / 6 W per channel). Dual fans top and dual fans bottom is fully supported.

  • Single-sensor mode — use the blue sensor and one fan at the top of the chimney. FridgeAir automatically switches to a more enhanced profile.

To see Herman Hits the Road install & review, [click here]

For full photo gallery including PCB detail [click here]

AirMix — Winter Condensation Guardian
£129.99

PRE-ORDER — Ships in 2 weeks

Storing your motorhome or caravan outside over winter? Condensation and damp are your biggest enemy. Cold nights, temperature swings and stagnant air create the perfect conditions for mould, bad smells, rot and expensive interior damage — all while your vehicle is sitting unattended for months.

AirMix helps with that.

Leave it inside your habitation area over winter and it silently monitors temperature and humidity, calculates the dew point, and automatically runs opposing fans to circulate air before condensation can form. Completely battery backed — no mains, no vehicle power, no hookup needed. Just switch it on, close the door, and leave it to do its job all winter long.

No app. No Bluetooth. No setup. Switch it on and walk away.

What AirMix does:

  • Monitors temperature and humidity continuously using a precision SHT40 sensor

  • Calculates dew point — the real indicator of condensation risk, not just humidity alone

  • Pre-sniff pulse — runs fans briefly before each sample to flush stagnant air from the AirMix chimney and get a true reading

  • Automatically runs opposing fans when condensation risk is detected — one draws air in, one pushes air out

  • Adaptive monitoring — increases check frequency to every 5 minutes after a dew event until conditions are safe

  • Seasonal activation latch — LED shows 2 flashes after a dew event so you know it has been working during storage

  • Battery backed — runs completely independently from a quality RS Pro 18650 lithium-ion cell

  • USB-C charging — charge before you store, lasts the winter

  • LED guide printed on the enclosure — 1 flash = ready, 2 flashes = activated, 3 flashes = charge soon

  • Boot self-test fan dance — confirms both fans working at startup

  • Standard camera tripod mount — brass insert fitted, position it anywhere in your habitation area

Freestanding or tripod mounted — goes anywhere:

AirMix sits flat on any surface or mounts directly onto a standard camera tripod using the brass insert fitted to the base. Position it exactly where condensation is a problem — under a bed, on a worktop, in a wardrobe space. No drilling, no permanent installation, completely repositionable season to season.

Before you store for winter:

  • Charge AirMix fully via USB-C

  • Switch on and confirm 1 flash heartbeat — ready

  • Place in your habitation area

  • Close up your motorhome or caravan and leave

When you return in spring — 2 flashes on the LED tells you AirMix has been working. Your van is protected.

What's in the box:

  • AirMix unit in carbon fibre PLA enclosure

  • RS Pro 18650 lithium-ion cell installed — PCB protected, overcharge and over-discharge protected, UN and RoHS certified, original manufacturer's packaging included

  • Quick Start Guide

Technical:

  • Supply: RS Pro 18650 Li-ion cell, 3.7V 2600mAh, USB-C charging

  • Fans: dual opposing 5V PWM, variable speed

  • Sensor: SHT40 precision temperature and humidity

  • Dew point algorithm: August-Roche-Magnus

  • Activation threshold: RH ≥ 70% or dew point margin ≤ 2.5°C

  • Fan run: full power 60 seconds, cruise 70% for 5 minutes

  • Check interval: 1 hour normal, 5 minutes after dew event

  • LED: 1 flash = ready, 2 = activated, 3 = low battery, 6 = sensor fault

  • Tripod mount: standard ¼" camera fitting via brass insert

  • Handbuilt and tested in the UK by Digconn Systems

Lotus Esprit Headlight Pod Lift Module
£325.00

The original Lotus Esprit headlight pod control module (A082M6363F) is no longer available from Lotus or GM. Over time these original units commonly fail due to overheating, failed relays, cracked solder joints resulting in unreliable stall detection and MOSFET burnouts.

This Pod Lift module is a modern, direct drop-in replacement designed to solve those problems and restore reliable headlight pod operation.

Key features

  • Position memory — remembers pod position even after battery disconnect

  • Independent motor stall detection

  • Obstruction safety cutoff

  • Ultra-low idle current — ideal for long-term storage

  • Conformal coated for protection against moisture, condensation and vibration

  • Direct drop-in fit — no wiring modifications required

  • Custom 3D-printed carbon black PLA-CF enclosure

  • Hand-built and fully tested in the UK by Digconn Systems

Replaces

  • Lotus part number: A082M6363F

  • GM part number: GM16523917

Confirmed compatibility

  • Lotus Esprit (1989–2004)

  • Renault Alpine A610

Also expected to fit (pending confirmation)

  • Buick Reatta (1990–1992)

  • Oldsmobile Toronado / Trofeo (1990–1992)

  • Pontiac Firebird / Trans Am (1990–2002)

  • Pontiac Sunbird (1990–1994)

  • Chevrolet Corvette C5 (1997–2004)

Important note The Lotus Esprit and the Renault Alpine A610 are the only vehicles fully tested and confirmed. The other models share the same GM part number and are expected to be compatible, but have not yet been independently verified. If you own one of these vehicles, please contact us using the contact page before ordering.

Full technical details are available on GitHub:

Click for technical Detail