Holiday imperial 2001, Owner'S Manual, Page: 247 / 301

Chassis Information
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
I M P E R I A L
1 0 • 2 4 7
The air dryer is located underneath the motorhome next to
the transmission. The air dryer removes moisture from the
compressed air system. This is important because if air con-
tains moisture it can freeze and prevent operation of brakes or
other pneumatic operated items.
The air dryer has 3 functions: it cools, filters and dries air
going through the motorhome’s systems. If an excessive
amount of water is present when performing the monthly air
tank drain service it may be an indication the filters inside the
air dryer need to be changed.
The following conditions can also cause water accumu-
lation and should be considered before replacing filter:
• An outside air source has been used to charge system.
• In areas where a 30º range of temperature occurs in
one day small amounts of water can accumulate due
to condensation. Under these conditions moisture is
normal and should not be considered a problem.
There are two filters in the air dryer that will need to be periodically
checked and changed if necessary. First is the spin-on desiccant filter, second
is the replaceable coalescing filter. Depending on how often the vehicle is
driven, filters will need to be checked or replaced every 6 months to 1 year.
Remove coalescing filter to determine amount of contamination. If the
filter looks black, filters need to be changed. If it is grey or white the filters
are fine. Whenever you need to change filters make sure you change both
filters, coalescing and desiccant, at same time. To remove filters unscrew
desiccant filter and remove it. Next, reach in and remove coalescing filter.
The front and rear air tanks should be manually drained once a month, or
more, depending on operating conditions where humidity is high. The front
air tank has a drain valve for both the wet and dry side. The rear air tank
only has one drain valve. Open the drain valves until all air is purged from
tanks, allowing five extra minutes for moisture to be expelled. Remember to
close the tank drain valves. Both air tanks have a pressure relief valve which
is set to approximately 130 psi.
AIR STORAGE
TANKS
AIR DRYER