Takeuchi TB175W, Руководство по ремонту

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III-79 TB175W
Start the engine and set to a fast idle of 1200 to 1500 RPM. Turn on the air
conditioner. After a quick in-cab performance test of control function, blow-
er speeds and air flow, set the AC system controls to maximum cooling and
blower speed on high. All windows must be closed. If cab temperature is hot (rig
has been sitting in the sun with the windows closed), open the windows for
a minute or so to let the hot air out. Run the engine and air conditioner about
five minutes for the system to stabilize. In hot humid weather or where the
AC condenser can’t receive adequate air flow from the engine fan you may
have to use a floor mounted fan to force sufficient air flow through condens -
er fins. This helps to stabilize the system by simulating ram air flow found
under normal operating conditions.
When a vehicle has a tilt cab or hood and the condenser is part of the
grill, you must use the floor fan to get air to the condenser. You could tilt the
cab or hood back to normal position, carefully routing the manifold gauge
set and hoses away from moving parts. Then place the gauges so you can
read system pressure.
Troubleshooting by Manifold Gauge Set Readings
The series of figures that follow (Figures 8-6 through 8-15) show gauges with
typical readings indicating AC system problems. Each figure is followed by trou -
bleshooting tips, probable causes for the gauge readings shown, and appropriate
service and repair procedures.
Low Refrigerant Charge in the System
Tip: You see bubbles in the sight glass. The air from vents in
the cab is only slightly cool.
Cause: Insufficient refrigerant (charge) in the system.
Troubleshooting & Service Procedures
Figure 8-5
Gauge reading, low refriger-
ant charge in the system.