Swift Motorhome Owners Service Manual page 194

Acrylic (Plastic) Window Cleaning
The material used to produce most caravan
and Motorhome windows is acrylic plastic.
While the acrylic used is very durable, it is
able to be scratched with relative ease and
therefore, care must be taken when clearing
your vehicle not to use aggressive clearing
products. Equally, care should be taken when
using a drying cloth that it is clean and free
from grit.
Condensation
What is condensation
Condensation is the process of change of
water from its gaseous form (water vapour)
into liquid water when it comes into contact
with a surface that is cold. Condensation
generally occurs when warm air cools quickly
and looses its capacity to hold water vapour,
and as a result water vapour condenses to
form droplets.
Why condensation occurs
Condensation occurs when warm moist
air meets a cold surface. The level of
condensation will depend upon humidity
levels, how moist the air is and how cold the
surfaces are they come into contact with.
If the temperature falls below the dew
point temperature, it is quite normal for
condensation to occur on any material within
the caravan that is cold, for example the
external walls, plastic windows etc.
When condensation occurs
Condensation occurs usually in winter months,
because ambient temperatures are colder
(leading to cold surfaces) and windows and
roof vents are opened less so the moist air
cannot escape.
Where condensation occurs
Condensation will occur where warm moist air
is put into the atmosphere in areas such as in
bathrooms (during showering) and in kitchen
areas (during cooking).
In the enclosed space of a motorhome, the
moist air from the kitchen or bathroom areas
will inevitably transfer to the rest of the vehicle,
CON DE NS AT ION
which in turn condenses on cold surfaces
leading to visible water droplets. This issue
is compounded by warm moist air being
generated from normal breathing.
Condensation will also form in cold areas
where air movement and ventilation is
restricted (e.g. cupuboards, wardrobes, under
beds, etc.)
What is important
It is important to provide ventilation and air
flow, so that warm moist air can escape, or
be externally cooled, and to use the heating
reasonably by not making the motorhome
too warm such that people perspire, as this
will only serve to generate more moist air and
therefore more condensation.
However, in particularly cold periods,
where the external ambient temperatures
are low, condensation may still form on
external walls as the insulation levels may
well not be thermally able to cope with the
difference between the internal and external
temperatures.
How can you prevent
condensation
Provide ventilation so that moist air can
escape.
a. Good ventilation of the vehicle when
cooking or when drying clothes, footwear
or pets is essential. Observe when windows
begin to show signs of misting and increase
ventilation by opening slightly by 1cm or
opening a roof vent, as these will help, but
keep the habitation door closed as much as
possible to retain heat.
b. If drying damp clothes or towels, open a
window to ventilate the area and allow the
moist air to escape.
c. Try to make sure that the caravan is partially
heated. It can take a long time for a cold
caravan to warm up, so it is better to have a
small amount of heat for a long period then
a lot of heat for a short time.
d. After showering, keep the bathroom window
or skylights open, and shut the bathroom
door long enough to dry off the room.
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