wallas 22 GB, Manual

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Installation
en
There has to be minimum 100 cm
2
(16 square inches) ventilation hole in
the space where the heater is installed.
Warm air ducting of the heater
It is important to plan the proper routing of the duct and the locations of the air reg-
isters. It is good to locate the heater as near as possible to the area being heated.
Avoid the use of sharp bends in the ducting and keep overall bends to a minimum.
Outlet ducting
Heated air is distributed through the boat with 3410 ø 75mm duct. Multiple outlets
can be installed by adding 3413 ø 75mm “Y” fittings leading to various locations.
All duct to “Y” and duct to register connections should be clamped.
The 3411 air registers are adjustable for direction and flow and located at each
duct termination point. It is important that sufficient flow is allowed by the installed
registers to maintain (limit) the heater temperature. To ensure this for some ap-
plications, the adjustment flap of the register in the bigger heated space, will be
removed. Too much resistance in the ductwork (too many flaps closed) and the
heater may overheat and shut down.
If the heater will be used mainly with thermostat control, the control panel should
be located in the largest heated area. To minimize the loss of heat energy, any long
runs and/or runs in areas that do not require heating can be insulated using 3412
insulation. Insulation nearer the heater will be more effective than insulation at the
far ends of duct runs.
Inlet ducting and makeup air
The heater can take air for heating (makeup air) from either the heated area (return
air) or from outside the boat (fresh air). In most cases, a mixture of both is the
best choice. The upper of the 2 x ø 75 mm intake air ducts should be installed to
take fresh air from outside and the lower return air from inside of the boat. In-
take air grills 4411 should be installed into the head of the inlet ducts to preclude
foreign objects from entering the heater. Protect the outside grill from splash water,
spray etc. If the makeup air will be taken from the same space where the heater
is installed, there is no need for the inlet air ducts, but protective grills should be
present. There has to be minimum 100 cm
2
(16 square inches) ventilation hole in
the space where the heater is installed.
Ducting runs
To enable low power consumption, the blower power is limited. It is important that
diameters in ducting and air supply holes are as large as possible.
Long air ducting will weaken the total effect, as the flow will be reduced due to
friction losses and loss of temperature through the walls of the ducts. Temperature
loss can be reduced with the insulation sock 3412 .
Heater installations in diesel engine spaces must be fitted with inlet
ducting bringing fresh air from outside the boat, return air from inside
the heated cabin or both. The heater should NEVER take inlet makeup
air from the engine spaces.
D10151A
- 80 -
22 GB / 30 GB
490529