Buying a winterized motorhome:
winterized vs. winter-proof

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 four 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”.