SERVICE
HS25
UNIT
INFORMATION
1993 Lennox Industries Inc.
Corp. 9327-L3
Litho U.S.A.
HS25 SERIES UNITS
The HS25 is a high efficiency residential split–system
condensing unit which features a scroll compressor. It
operates much like a standard condensing unit, but the
HS25’s scroll compressor is unique in the way that it
compresses refrigerant. Several models are available in
sizes ranging from 1–1/2 through 5 tons. The series is de-
signed for use with an expansion valve in the indoor unit.
This manual is divided into sections which discuss the
major components, refrigerant system, charging pro-
cedure, maintenance and operation sequence.
All specifications in this manual are subject to change.
SCROLL COMPRESSOR
DISCHARGE
SUCTION
ÎÎÎ
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I–APPLICATION
All major components (indoor blower/coil) must be
matched according to Lennox recommendations for
the compressor to be covered under warranty. Refer to
the Engineering Handbook for approved system
matchups. A misapplied system will cause erratic op-
eration and can result in early compressor failure.
II–SCROLL COMPRESSOR
The scroll compressor design is simple, efficient and
requires few moving parts. A cutaway diagram of the
scroll compressor is shown on the cover. The scrolls
are located in the top of the compressor can and the
motor is located just below. The oil level is immediate-
ly below the motor.
The scroll is a simple compression concept centered
around the unique spiral shape of the scroll and its in-
herent properties. Figure 1 shows the basic scroll form.
Two identical scrolls are mated together forming con-
centric spiral shapes (figure 2). One scroll remains sta-
tionary, while the other is allowed to orbit (figure 3).
Note that the orbiting scroll does not rotate or turn but
merely orbits the stationary scroll.
