Huntleigh Flowtron AC550 User manual

247901 Issue 1
Mar 1998
AC550 Flowtron®Excel system
Service Manual
Huntleig
h
HEALTHCARE

247901 Issue 1
Mar 1998

PRELIMINARIES
Revision Record
All revisions incorporated in this copy of the manual must be recorded below.
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247901 (i) Issue 1
March 1998

247901 (ii) Issue 1
March 1998

Preface
Read and understand this manual before attempting to service or repair the
equipment.
Warnings, Cautions and Notes
WARNINGS given in this manual identify possible hazards in procedures or
conditions which, if not correctly followed, could result in death, injury or other
serious adverse reactions.
Cautions given in this manual identify possible hazards in procedures or
conditions which, if not correctly followed, could result in equipment failure or
damage.
Notes given in this manual are used to explain or amplify a procedure or
condition.
General Warnings
247901 (iii) Issue 1
March 1998
This manual is intended to be used only by qualified Huntleigh Healthcare
service technicians. In the event that the manual is provided to a customer in
response to customer requirements, the customer is advised not to attempt
repairs and to direct any required service to qualified Huntleigh Healthcare
service technicians. In no event will Huntleigh Healthcare be responsible for
any service performed by customers or third parties.
WARNING
Before performing any service or maintenance procedures,
ensure that the equipment has been adequately decontaminated.
Voltages in excess of 30 volts RMS or 50 volts DC can, in certain
circumstances, be lethal. When working on equipment requiring
exposure to live, unprotected conductors where such voltages
are present, extreme care must be exercised.

247901 (iv) Issue 1
March 1998

Contents
PRELIMINARIES ..................................(i)
INTRODUCTION ..................................1.1
About This Manual ................................1.1
General Description ...............................1.2
Technical Description ..............................1.3
Pneumatic Schematic ..............................1.4
Valve Sequence .................................1.5
Electrical Wiring Schematic ...........................1.6
General Assembly ................................1.7
OPERATIONAL MAINTENANCE .........................2.1
Routine Checks .................................2.1
TROUBLESHOOTING ...............................3.1
Preliminary Checks ...............................3.1
Service Mode Checks ..............................3.2
Loss of Electrical Power .............................3.2
PREVENTIVE MAINTENANCE ..........................4.1
Servicing Protocol ................................4.1
Procedure to Remove Top Cover .......................4.1
General Service - Pump............................4.2
Pressure Output and Calibration Checks ....................4.2
Pressure Control Calibration ...........................4.3
Pressure Display Calibration...........................4.4
Calibration Check ...............................4.4
Pressure Display Re-calibration Procedure ..................4.4
Component Part Replacement..........................4.6
Dismantling the Pump Unit ..........................4.6
Replacing the Compressor Assembly Components .............4.6
General Checks .................................4.7
Electrical Safety Checks .............................4.7
Ground continuity test .............................4.7
Leakage current test .............................4.7
SERVICING THE PUMP ..............................5.1
Replacing the Main Printed Circuit Board ....................5.1
247901 (v) Issue 1
March 1998

Replacing the Motor/Gear Box Assembly ....................5.1
Replacement of Front Panel Assembly .....................5.1
Replacing Main PCB or Front Display Panel ..................5.2
Replacing the Motor Gearbox Assembly (247071) ...............5.3
Replacing Display PCB .............................5.4
Replacing the Electrical Supply On/Off Switch..................5.4
Replacing the Pressure Control Knob ......................5.4
Locking Knob Option (Part 247087) .......................5.4
Pressure Control Assembly ...........................5.5
Replacing the Pressure Control Assembly....................5.6
Replacing the Connectors ............................5.6
Replacing the Electrical Cord ..........................5.6
Buzzer Replacement...............................5.7
Hang Strap Assembly ..............................5.7
TECHNICAL DATA .................................6.1
SPARE PARTS ...................................7.1
247901 (vi) Issue 1
March 1998

1 INTRODUCTION
1.1 About This Manual
This manual contains information on servicing the AC550 Flowtron®Excel
system which consists of the pump and a pair of garments. The manual is
sectioned with tabbed dividers for ease of use and consists of the following
sections.
Section 1 - Introduction: contains a general description of the overall
operation of the system and a technical description of the construction of the
pump and principles of operation.
Section 2 - Operational Maintenance: describes both functional and static
checks to ensure correct operation during the service life of the system.
Section 3 - Troubleshooting: contains tables of fault symptoms, possible
causes, and suggested steps to correct the problem.
Section 4 - Preventive Maintenance:contains a list of parts which are
replaced periodically to ensure the correct operation of the system.
Section 5 - Servicing The Pump: contains illustrated procedures for
replacing pump components.
Section 6 - Technical Data: contains a list of technical data.
Section 7 - Spare Parts: contains a list of spare parts that should be kept in
stock.
247901 1-1 Issue 1
March 1998

1.2 General Description
The Flowtron Excel system is a specially designed non-invasive system for the
prevention of deep vein thrombosis (DVT). The application of external
pneumatic compression has two effects :
1. Augments venous blood flow velocity, thereby reducing stasis, and
2. Enhances fibrinolytic activity to reduce the risk of early clot formation.
The Flowtron Excel system is comprised of a pressure regulated pump unit and
a pair of calf or thigh length, single patient use garments. The pump provides
intermittent cycles of compressed air which alternately inflate the
single-chambered garments. The compression applied on the extremity
augments venous blood flow velocity and stimulates fibrinolysis.
The pump operates on a 60-second, automatically timed cycle consisting of
approximately 12 seconds of compression followed by approximately 48
seconds of deflation. The recommended operating pressure is 40 mmHg, unless
otherwise prescribed by a physician.
The pump unit is a piece of precision equipment, and providing it is handled
and properly serviced (normally every 12 months), should give long and
trouble-free service.
Controls of the pump unit consist of :
·Electric power switch (green rocker switch) illuminated when in ‘ON’
position, as is the green LED on the top panel.
·Pressure control knob. Pressure adjustment range is between 30 mmHg
and 60 mmHg.
·Single Leg button with amber LED, when selected allows for single
garment use without the alarm being falsely activated.
·Illuminated display that indicates system pressure and also fault messages.
The Flowtron Excel pump unit has both audible and visual alarms. When a fault
condition occurs, the red LED flashes and the description "HI, Lo or F" is
indicated on the display panel on the pump. If the fault condition is unaltered,
the audible alarm will increase in pitch until the fault is corrected and the
system is reset.
247901 1-2 Issue 1
March 1998

1.3 Technical Description
The pump is an electromechanical unit designed to supply compressed air to the
garments while controlling the inflation time and pressure.
In addition, an electronic module monitors pressure and fault conditions only. It
is independent of the control system, and functions independent of thepump
pressure.
Referring to the schematic diagram (Figure 1.1), the key parts of the pump are
as follows.
1. Compressor
This provides a constant flow of air to the pneumatic system, thus allowing
inflation of the garments.
2. Rotary Valve
This controls the delivery of pressure to the garments and sets the duration and
frequency of the garment inflation.
3. Pressure Control Valve
This sets the maximum pressure that can be delivered to the garments.
4. Differential Pressure Transducer
This measures the pressures at each garment part and provides the monitoring
system with the means of accurately measuring relative pressures in the two
garments.
5. Electronic Monitor
The electronics in the monitoring system perform continuous checking of the
operation and performance of the pneumatic circuit. In the event of a detected
fault, the electronic monitoring system generates both audible and visual alarms.
6. LED-Pressure and Message Display
The monitored pressure is displayed on the dual, seven segment display in real
time. In the event of a detected fault, the relevant fault message is displayed.
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March 1998

1.4 Pneumatic Schematic
247901 1-4 Issue 1
March 1998

1.5 Valve Sequence
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1.6 Electrical Wiring Schematic
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March 1998

1.7 General Assembly
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March 1998

247901 1-8 Issue 1
March 1998

2 OPERATIONAL MAINTENANCE
2.1 Routine Checks
These procedures should be carried out each time the system is used.
1. Inspect the pump unit for external damage to case, controls, and
connections.
2. Inspect power cord for damage or twisting, and replace if necessary.
3. Check that the control knob is set to the recommended setting of
40 mmHg.
4. Check the calibration of the control knob and pressure display. In
normal operation, when the display reads 40, the knob pointer should
be somewhere within the 40 arc. If not, the pump should be returned
to Service for recalibration.
5. Check the hanging hook is secure.
6. Check the feet are in place.
247901 2-1 Issue 1
March 1998

247901 2-2 Issue 1
March 1998

3 TROUBLESHOOTING
The Flowtron®Excel pump unit has both an audible and a visual alarm. If a
problem occurs, the system will sense the fault and briefly flash a message on
the display. It will not alarm immediately in order to screen out false alarms
due to normal patient movement. If the same fault continues on ten successive
inflations, the audible alarm will sound and a flashing message will remain on
the display until corrective action is detected.
Note: The exception is the “F” system alarm which will be activated on sensing
the fault on the first occasion.
3.1 Preliminary Checks
HI or Lo faults have probably been caused by garment or tubing problems.
Garment faults should be checked as below.
Display Problem Corrective Action
1. Loose fitting garment.
2. Hose disconnected at
garment.
3. Garment leak.
4. Low pressure.
1. Rewrap snugly.
2. Check the hose connection
at garment end.
3. Check garment and
replace if faulty.
4. Refer to service.
1. Hose kinked causing a
blocked tube.
2. Hose disconnected at pump.
3. Single garment attached
without pressing “Single Leg”
button.
1. Check hoses for kinks
or obstructions.
2. Check the hose connection at
pump outlet.
3. Press “Single Leg” button if
only one garment is used.
Pump failure.
DO NOT USE PUMP.
Refer to service.
In the unlikely event of a monitoring system electronics failure, the red LED on
the top panel will flash rapidly to indicate monitoring system failure.
If garment faults have been eliminated and the fault persists, proceed to Service
Mode Checks.
247901 3-1 Issue 1
March 1998

3.2 Service Mode Checks
Service mode gives additional information on the type of alarm fault.
To access the service mode, hold the Single Leg button down for
approximately 13 seconds. The unit will then ‘beep’ and the red LED on the top
panel will be constantly displayed.
The main display will now indicate the actual pressure to 1 mmHg resolution
and also display the detailed fault codes.
Fault codes and counter measures are described in the following table (see
pages 3-3 and 3-4).
3.3 Loss of Electrical Power
Power loss can be due to the following :
1. No electricity supply at wall outlet.
2. Faulty wall outlet.
3. Damaged cord or cord plug.
4. Defective fuse link.
5. Damaged internal wiring.
6. Cord plug inadvertently removed from wall outlet.
3.4
247901 3-2 Issue 1
March 1998