Dip Switch Settings - PREVOST H3-41 Maintenance Manual

2. Loosen rotation locking screw two (2) turns
(do not remove). Then, remove PCB as-
sembly from the back plate of the sensor.
3. Insert the wiring into one of the wire chan-
nels on the sensor's back plate.
4. Securely affix the sensor's back plate to the
wall using #6X3/4'' screws.
5. Reinstall the PCB assembly and then,
tighten rotation locking screw.
8.5.2

Dip Switch Settings

Adjust DIP switches as follows:
1=off 2=off 3=off
4=on 5=off 6=off
8.6 EMERGENCY BUZZER
The lavatory emergency buzzer is mounted on
the alarm junction box in the front service
compartment and sounds when the emergency
call push-button switch
compartment is activated. For specific wiring
information, refer to wiring diagrams. To remove
the emergency call push-button switch, proceed
as follows:
1. Remove both Phillips-head screws retaining
pushbutton switch plate to wall.
2. Remove steel plate located on L.H. side of
pushbutton switch.
3. Remove switch through this opening, taking
care to disconnect electric wires.
8.7 FRESH WATER TANK
The fresh water tank located at rear of lavatory
wall (over cleaning cabinet), supplies water to
the washbasin by gravity. Two tubes are con-
nected in the upper section of tank (Figure 29).
One serves as overflow as well as vent tube and
runs along the wall to the underside of the
lavatory close to the engine air filter housing,
while the other tube is connected to the fresh
water fill valve which is mounted besides the
engine oil reserve tank.
A third tube connected in the lower section of
fresh water tank is provided with a T-connector
and allows fresh water to flow to the washbasin
faucet and to the low temperature water safety
valve for automatic or manual draining. An
in the lavatory
SECTION 23A: ACCESSORIES - H3 SERIES
access panel, located at rear of last R.H. side
row of seats and secured in place using 6
Phillips-head screws, allow access to the
cleaning cabinet and fresh water tank tubing,
fresh water tank heater and different wiring
connectors.
8.7.1 Fresh Water Tank Heater (Optional)
75 watts, 110 volts AC immersion-type water
heater may have been installed in the bottom of
the fresh water tank. The heated portion of
element must be immersed at all times to ensure
proper heater life. The 110-120 volts in-station
connector mounted on the engine compartment
rear door provides the water heater power
source.
8.7.2 Fresh Water Tank Draining
The fresh water tank can be drained by simply
opening the fresh water drain cock (Figure 29).
Don't forget to close cock when draining is done.
CAUTION
If fresh water tank heater is inoperative or not
installed on your vehicle, water should be
drained from reservoir under cold weather
conditions since it might freeze and damage
both reservoir and connecting links.
8.7.3 Fresh Water Tank Filling
Plug the fresh water supply hose to the fresh
water tank fill connection (Figure 29); fill the tank
until the overflow tube leaks, signaling that tank
is full.
WARNING
Never put antifreeze in fresh water tank;
antifreeze is toxic.
WARNING
If tank has not been drained for an extended
period of time, draining and filling operations
must be repeated three (3) times in order to
clean tank and eliminate contaminated water.
PA1621 Maintenance Manual All Series | Jan 2020
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