Dometic Mini Heki S
Official technical documentation and workshop diagnostics for Mini Heki S.
Technical Specifications
Master Troubleshooting & Diagnostics Matrix
| Error Code / Indicator | Symptom / Meaning | Possible Cause | Step-by-Step DIY Fix | Suggested Actions |
|---|---|---|---|---|
N/A | Roof window does not lock properly before journey | Improper closure or mechanical obstruction | Inspect the roof window for damage, and make sure it's fully locked before setting off. | DIY Safe |
N/A | In strong sun, the roof dome turns cloudy | Normal thermal reaction of acrylic glass under high solar radiation | No action needed - it clears again on its own once it cools down. | DIY Safe |
N/A | Protective PE film cannot be removed without leaving residue | The protective film's been left in sunlight too long | Ensure protective film is removed immediately after installation to avoid solar degradation of the adhesive. | DIY Safe |
Frequently Asked Questions
Q: What are Dometic rooflight panes made of, and why?
PMMA (acrylic). It's very clear and easy to form and shape with heat. Dometic says it looks like glass at half the weight and is around 30 times stronger, insulates well against heat and cold, and stands up to weather from -40°C to +80°C.
Q: What vehicles can Dometic rooflights be fitted to?
Motorhomes and campervans, caravans and panel-van conversions. They come in many versions and Dometic describes them as dependable, simple to fit and long-lasting.
Q: What roof thickness do Dometic rooflights suit?
It varies by model - Dometic lists every rooflight's dimensions and specifications on its website. Before fitting one, measure your roof's thickness and check whether the cut-out (the gap between the inner and outer roof skins) needs reinforcing; if in doubt, ask the vehicle's manufacturer.
Q: How can I tell which Dometic rooflight I have, so I can replace it?
Look for the information printed on the pane before ordering. The PNC/SKU number and code identify when it was made and which spare parts it takes, and the letters and numbers along the bottom identify the glazing. Rooflights made after February 2016 also carry a label on the inside (on the Midi Heki, for example) - though there's no label on a Mini Heki.
Q: How much does a Dometic rooflight weigh?
Between about 2.9 kg and 22 kg, depending on the model.
Q: What size roof opening does each Dometic rooflight need?
400 x 400 mm for the Mini Heki S, Mini Heki Plus and AirQuad; 700 x 500 mm for the Midi Heki; and 960 x 655 mm for the Heki 4 Plus, Heki 3 Plus, Heki 2 and Heki 1.
Q: Why is there condensation between the panes of my rooflight?
Acrylic is an organic material that absorbs tiny amounts of water, so moisture can work its way through the acrylic, making the air wetter in the gap between the two layers of double glazing. When it gets colder outside, the air in that gap cools and the excess moisture condenses on the coldest surface - the inside face of the outer pane.
It isn't a fault. To clear it, ventilate the vehicle to bring the humidity down (good air circulation helps), or raise the temperature inside, since warmer air holds more moisture - then give it time to disappear.
Q: What causes scratches on my rooflight?
Usually dust or grit blown against it, whether you're driving or parked. Brushing against tree branches on the road, or washing it with an abrasive sponge, can scratch it too.
Q: What causes cracks in my rooflight?
Cracks in acrylic are usually caused by 'stress corrosion' - chemical attack on the material while it's also under tension. Over the years, changes in temperature and repeated wetting and drying create slight stresses in the surface; on their own these are harmless, provided the pane is cleaned and cared for properly. But cleaning products that aren't suitable for acrylic attack the stressed surface and can eventually destroy the pane.
So never use glass cleaner, general-purpose cleaner, abrasives, washing-up liquid or anything containing alcohol.
Q: What should I clean my caravan or motorhome windows and rooflights with?
Only a cleaner made for acrylic glass. Never use harsh products - glass cleaner, general-purpose cleaner, abrasives, washing-up liquid - or anything containing alcohol.
Q: Where can I get spare parts for a roof hatch, service hatch or sliding window?
Your caravan or motorhome dealer can order them for you - Dometic's website has a dealer locator to find one.