Buying a winterized motorhome:
winterized vs. winter-proof

In common parlance, the two terms are interchangeable. To the layman, they describe a caravan or motorhome you can have a winter holiday in without freezing.

But this is far from the case. Although the two terms sound similar, there are significant differences between them. Both are based on official standards are can therefore be clearly and unmistakably defined.

In this article we will show you the differences and what to look out for when buying a winterized motorhome.

Manufacturers use the two terms to refer to grades II and III as defined in the DIN standards EN 1645-1 for caravans and EN 1646-1 for motorhomes, for which there is a precisely prescribed test procedure with four phases:

Winterproof (grade II)

Phase 1 - cooling down:

The test vehicle is cooled down to 0 °C over a period of at least ten hours. For this, all doors and windows are opened to cool down the vehicle completely.

Phase 2 – heating up:

The aim is to heat up the interior of the test vehicle as quickly as possible from a starting temperature of 0 °C. The centrally located measuring point, one metre above the interior floor in the middle of the living area, must heat up to + 20 °C within two hours, whereby the temperature difference at five other measuring points inside the vehicle must not exceed seven °C.

If the test vehicle passes the grade II test procedure, is qualifies as “winterproof”.

Winterised (grade III)

Phase 1 – cooling down:

The test vehicle is cooled down to -15 °C over a period of at least ten hours. For this, all doors and windows are opened to cool down the vehicle completely.

Phase 2 – heating up:

The aim is to heat up the interior of the test vehicle as quickly as possible from a starting temperature of -15 °C. The centrally located measuring point, one metre above the interior floor in the middle of the living area, must heat up to + 20 °C within two hours, whereby the temperature difference at five other measuring points inside the vehicle must not exceed seven °C.

Phase 3 – stabilisation time:

After a one-hour stabilisation period, during which the test vehicle is kept at an interior temperature of + 20 °C by the heater, the water tanks are filled.

Phase 4 – plumbing test:

After a further hour, all the plumbing and taps are tested to make sure they are clear and functional, i.e. the water inside them hasn’t frozen.

If the vehicle passes the grade III test procedure, it qualifies as “winterised”.

Winter camping with HYMER

All HYMER motorhomes are supplied ready winterised. The HYMER camper vans too can be winterised with the appropriate optional extras, making it ideal for winter camping.

HYMER subjects its motorhomes, RVs and caravans to a proper cold stress test and puts them through the stringent grade III test procedure. This is performed at Truma in Munich for hot air heating systems and in the ALDE cold chamber in Sweden for hot water heating systems.

Back in 1978, HYMER introduced the still-patented PUAL design which guarantees all HYMER motorhomes a clear quality advantage in terms of (body) stability and insulation. The excellent insulation of the closed-pore PU foam guarantees pleasant temperatures throughout the year and low gas consumption in winter. The thermal insulation is equivalent to a 80 cm-thick solid brick wall in the motorhomes.

Fully winterised: 

The suitability of HYMER motorhomes for year-round use gives it an advantage over many other makes.

Clever climate control solutions such as the insulated service installations and tanks, heated dashboard, heated exterior lockers and double-glazed framed windows, or the sophisticated heating and ventilation system and HYMER’s unique bonding technology make every Hymermobil fit for all weathers. That way you can enjoy the snowy winter landscape from your cosy warm interior, no matter how cold it is outside.

The HYMER camper vans have likewise scored top marks in cold chamber tests. Smart ideas and solutions from HYMER Original Parts & Accessories do even more to enhance the pleasure of a winter holiday: interior insulation for the living room windows and cab, a height-adjustable insulating element for the rear section and the perfectly insulated pop-top roof keep the living area cosy and warm.

Further offers and information

Being well-informed improves your experience on the road

HYMER service goes above and beyond your vehicle. We want nothing to come between our customers and their passion for travelling, which is why we provide helpful information and tips.

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