Manifold Gauge Set; Low Side Pressure Gauge; High Side Pressure Gauge - Aston Martin DB7 Workshop Manual

Air Conditioning
Manifold Gauge Set
5=2?
Manifold Gauge Set
The manifold gauge set is a most important tool for
fault diagnosis and system efficiency assessment.
The relationship to each other of HIGH and LOW
pressures and their correlation to AMBIENT and
EVAPORATOR temperatures must be compared to
determine system status. Because oi the heavy
reliance upon this piece of equipment for service
diagnosis, ensure that the gauges are calibrated
regularly and the equipment is treated with care.
BLUE LOW SIDE
RED HIGH SIDE
LOW
m
m
Manifold.
The manifold is designed to control refrigerant
flow. When connected into the system, pressure is
registered on both gauges at all times. During
system tests both the high and low side hand valves
should be closed (rotate clockwise to seat the
valves). The hand valves isolate the low and the
high sides from the centre (service) hose.
Low Side Pressure Gauge.
This compound gauge is designed to register positive
and negative pressure and may be calibrated as
follows:
• Full Scale Deflection - 0 to 24 bar pressure
in a clockwise direction
• O t o l bar FSD negative pressure in a counter
clockwise direction.
High Side Pressure Gauge.
This pressure gauge may be calibrated from 0 to 34
bar FSD inaclockwisedirection. Depending on the
manufacturer, this gauge may also be of the
compound type.
Figure 1
The gauge set (Fig. 1) consists of a manifold fitted with:
1 Low side service hose - BLUE.
2 Low Side hand valve - BLUE.
3 Low pressure compound gauge - BLUE.
4 High pressure gauge- RED.
5 High Side hand valve - RED.
6 High side service hose - RED.
7 System service hose - NEUTRAL C O L O U R
(commonly yellow).
8-38
May 1996