White Magic PRO 1900, Owner'S Manual

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6. Preheater needs bleeding. To bleed air from it loosen the plug on top
of preheater and start engine and tighten the plug when air bubbles cease.
Don’t bleed preheater when the coolant is excessively hot – may cause
severe burns.
7. Using a large volume of water from the machine check the size of the tool
jets.
8. Water is flowing from the engine radiator; replace preheater and add
antifreeze to engine.
9. The exhaust diverter valve may be sticking or defective, or the vacuum solenoid
(electric vacuum switch on cross member) may be defective.
10. Hot water bypass solenoid may be stuck open, constantly bypassing water back
to the fresh water tank. (Usually indicated by the pressure gauge NOT staying at
0 psi when wand trigger is not depressed.) To check to see if the bypass sole-
noid is working correctly, do the following:
1. When the machine is cold, turn the key on the engine to the start position. It
is not necessary to start the machine at this time. Put the winterization /
water recovery switch in the normal position. Turn the thermostat knob
to high. Place a metal object (wrench or screwdriver) against the sole-
noid housing. There should be MINIMAL magnetization of the housing.
Momentarily flip the winterization / water recovery switch to winterize.
The solenoid housing should now be magnetized, indicating it is electri
cally functioning properly. If the solenoid housing is magnetized in the
normal settings, the heat control thermostat on the face panel has most
likely failed and will need replacing.
2. If the solenoid housing is not magnetized in the normal settings, it is possible
there is debris in the base of the solenoid allowing hot water to constantly
bypass back to the fresh water tank. To check for “debris” leak by, do
the following:
1. When the machine is cold, disconnect the solenoid assembly at the up
per female Q.D. (#2) leaving the bottom side input hose Q.D. (#3)
connected.
2. Place a 1/4” male Q.D. into female Q.D. (#2) which will open the
Q.D. Let the solenoid assembly hang into a bucket or point in a
safe direction and start the engine. With all settings in their nor
mal positions, no water should flow from the now open Q.D. (#2).
Water should only flow from here if the switch has been flipped
TROUBLESHOOTING GUIDE (continued..)
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