Huntleigh Flowtron DVT User manual

F048 Issue 3
Mar 2003
Huntleig
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HEALTHCARE
Flowtron®DVT
Service Manual

F048 Issue 3
Mar 2003

PRELIMINARIES
Revision Record
All revisions incorporated in this copy of the manual must be recorded below.
Section Page
No. Issue CN Inserted By Section Page No. Issue CN Inserted By
Issue 3 (i) F048
Mar 2003

Preface
Review 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 followed correctly, could result in loss of life or severe
personal injury.
CAUTIONS given in this manual identify procedures or conditions which, if
not followed correctly, could result in equipment damage.
NOTES given in this manual are used to explain or amplify a procedure or
condition.
General Warnings
Issue 3 (ii) F048
Mar 2003
This manual is intended to be used only by Huntleigh Healthcare trained
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
Huntleigh trained service technicians. In no event will Huntleigh 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 Vrms or 50 Vdc can be lethal, in certain
circumstances. When working on equipment requiring exposure to
live unprotected conductors, where such voltages are present,
extreme care must be exercised.

Contents
INTRODUCTION .................................1-1
How To Use This Manual ..........................1-1
Technical Description ............................1-2
Servicing Protocol ..............................1-3
OPERATIONAL MAINTENANCE .........................2-1
Routine Checks ...............................2-1
TROUBLESHOOTING ..............................1-1
Preliminary Checks .............................1-1
Further Checks ...............................1-1
PREVENTIVE MAINTENANCE ..........................4-1
Pump Unit ..................................4-1
SERVICING THE PUMP .............................5-1
Dismantling the Pump Unit .........................5-1
Replacing the Alarm Light LED .......................5-1
Replacing the Audible Alarm ........................5-2
Replacing the On/Off Switch.........................5-2
Replacing the Fuse Holder .........................5-3
Replacing the Pressure Control Assembly .................5-4
Replacing the Alarm Module Assembly ...................5-4
Replacing the Timer Motor/Gear Box Assembly ...............5-5
Replacing the Electric Cord .........................5-5
Replacing the Compressor Air Inlet Sponge Filter ..............5-6
Replacing the Compressor Assembly ....................5-6
Replacing the Compressor Assembly Components .............5-6
Test Equipment Requirements ........................5-8
Test Instructions and Specifications .....................5-8
TECHNICAL SPECIFICATIONS .........................6-1
APPENDIX A ...................................A-1
Wiring Diagram ...............................A-1
Pneumatic Diagram .............................A-1
APPENDIX B ...................................B-1
Parts List...................................B-1
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Issue 3 (iv) F048
Mar 2003

1 INTRODUCTION
1.1 How To Use This Manual
This manual contains information for servicing the Flowtron®DVT system
which consists of a pump, a pair of compression sleeves and a tubeset. The
manual is partitioned with tabbed dividers for ease of use and consists of the
following sections.
Section 1 Introduction: includes a general description of the operation of
the system and a servicing protocol.
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 details of fault symptoms, their
possible causes and suggested steps to rectify the problem.
Section 4 Preventive Maintenance: contains a list of parts which must be
periodically replaced to ensure the correct operation of the
system.
Section 5 Servicing the Pump: contains illustrated procedures for
replacing pump components, testing and calibration.
Section 6 Technical Specifications: contains a list of technical data.
Appendix A Diagrams: contains electrical wiring and pneumatic diagrams.
Appendix B Parts List: a list of currently available spare parts.
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Mar 2003

1.2 Technical Description
The Flowtron®DVT System has been specifically designed to provide
prophylactic therapy for patients at risk of developing Deep Vein Thrombosis.
For optimum results it is recommended that Flowtron DVT be applied
pre-operatively and used continuously during the pre-, intra-, and post-operative
periods.
The system comprises :
1. Pressure regulator pump Model AC500/2
2. Suitable patient garments from the Flowtron DVT range
3. L550 Tubeset with snaplock connectors
Pressure regulated pump unit AC500/2 to be used with L550 and Flowtron DVT
garments only.
The pump inflates and deflates the garments on a one-minute cycle
(approximately 12 seconds inflating, 48 seconds deflating). During the cycle,
air is pumped to one outlet followed by the commencement of inflation at the
second outlet approximately 30 seconds later.
The pump unit is piece of precision equipment, and provided that it is handled
and serviced correctly (normally every 12 months), should give long and trouble
free service.
Controls and indicators on the pump unit comprise:
a) Power switch (green rocker switch) illuminated when in the ‘ON’
position
b) Pressure control knob. Pressure adjustment between 20 mmHg
and 60 mmHg
c) Red LED alarm indicator and audible signal indicates LOW and
HIGH pressure faults
Note: The Flowtron DVT pump is fitted with both audible and visual alarm
indicators. When a fault occurs the audible alarm sounds and the
LED illuminates.
F048 1-2 Issue 3
Mar 2003

1.3 Servicing Protocol
1.3.1 General Service - Pump
Initial Assessment (Visual Check):
a) Enclosure for integrity and cleanliness of top and base
b) Fittings for damage and security
c) Labels are secure and legible
Open Pump:
d) Wiring and terminations are secure
e) Tubing security and integrity
f) Components fastenings are secure
g) General condition inside is clean
Open Compressor:
h) Silencer bag weld seams
i) Bellows/armature blade assembly condition
General:
j) Check electric cord assembly for security
k) Clean condition of pump.
If any items in a) - j) appear defective, replace with appropriate spare part and
record action on service record sheet.
Re-assemble pump unit completely.
1.3.2 Testing
The following procedures should be carried out following any repair and as part
of the routine service.
Perform electrical safety checks, pressure, flow and calibration checks and
functional checks as given in Section 5.
Note: It is important to ensure that all tools which are used in servicing are
kept in good condition and test rigs for flow and pressure are regularly
calibrated to a reference gauge with calibration directly traceable to
the appropriate National Standards.
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Mar 2003

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2 OPERATIONAL MAINTENANCE
2.1 Routine Checks
These procedures should be performed each time the system is used.
2.1.1 Pump Unit
a) Inspect the pump unit for external damage to case, controls and
connections etc.
b) Inspect the electrical cord for damage, cuts, abrasion, twisting, and
replace if necessary.
c) Test all controls.
2.1.2 Garments
Check integrity of garments. Visually inspect for punctures, tears, damage to
connections, fasteners, tubes.
2.1.3 Tubeset
Check tubing and connectors for damage and replace if necessary.
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F048 2-2 Issue 3
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3 TROUBLESHOOTING
This section lists some of the problems which may occur after long periods of
time, and outlines the way in which to correct them.
The Flowtron DVT System has an audible and a visual alarm.
When a fault condition occurs, the audible alarm sounds and the red LED
illuminates.
The following checks should be performed by a trained Huntleigh Healthcare
person.
3.1 Preliminary Checks
Check the following before dismantling the pump unit.
1. Verify that all tubing connections on pump and garment are securely
fastened and in place.
2. If alarm still sounds, visually inspect tubing and garments for punctures
or tears.
This eliminates possible garment and tubing faults.
3.2 Further Checks
If the alarm stays on it could indicate:
3.2.1 Low-pressure fault
Check position of pressure control knob.
The alarm will sound if the pressure in the garment does not reach 28 mmHg.
Adjust pressure control knob if necessary. Refer to Section 4.
3.2.2 Constant-pressure fault
Switch the pump OFF and remove garments.
A constant pressure fault condition occurs when the timer motor stops rotating
(air not alternating). If this should occur, check integrity of the electrical
connections of the timer motor. If connections are sound and the motor still
does not rotate, the timer motor must be replaced.
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Mar 2003

3.2.3 Loss of air output pressure
If the garments do not inflate, check them for leaks and for the correct
connection of tubesets.
If the leak check is satisfactory the pump unit internal compressor must be
tested.
Switch OFF pump unit and disconnect the supply cord from the power
outlet.
1. Remove unit lid as described in Section 5.
2. Disconnect the compressor outlet tubes from the 4-way connector and
connect a Y-piece to the two tubes.
3. Connect a pressure gauge to Y-piece outlet.
4. Reconnect the power supply cord and switch on the pump.
The pressure reading should be at least 100 mmHg.
If the pressure does not reach 100 mmHg, disconnect the power supply again
and remove the compressor lid. Remove the silencer bag from the valve bodies
and connect the pressure gauge to each valve body in turn. The pressure
reading should once again be approximately 100 mmHg.
If this pressure cannot be reached, the bellow/armature assemblies and valve
bodies must be replaced. If 100 mmHg can be obtained, the silencer bag
assembly must be replaced.
Switch OFF the pump unit and disconnect the electric cord from the
power outlet before performing any repair work.
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Mar 2003
WARNING
Danger of electric shock. During the following tests live terminals and
conductors will be exposed.

3.2.4 Checking the Pressure-Control Assembly
If the compressor is operating correctly and the correct pressure cannot be
obtained at the pump outlets, the rotor/stator assembly and the pressure-control
assembly must be checked:
1. Remove the timer motor/gearbox assembly as described in Section 5.
2. Compress the rotary-valve assembly and remove the drive pin.
3. Check the bearing surfaces for cracks or bad scores. Also check the
security of the elbow connectors.
4. Remove the pressure-control assembly as described in Section 5.
5. Inspect the pressure control bags for leaks.
Any damaged parts must be replaced. It is recommended, in either case, that
the complete assembly is replaced.
Switch OFF the pump unit and disconnect the electric cord from the power
outlet before performing any repair work.
3.2.5 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 plug or electric cord
4. Defective fuse link
5. Damaged internal wiring
Evaluate each potential fault and correct as necessary.
3.2.6 Technical assistance
For technical assistance, contact:
Service Department
Huntleigh Healthcare Inc.
40 Christopher Way
Eatontown,
New Jersey 07724-3327
Telephone : [phone]
Fax : [phone]
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F048 3-4 Issue 3
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4 PREVENTIVE MAINTENANCE
The following preventive maintenance should be performed every 12 months
4.1 Pump Unit
Replace the following components:
1. Silencer bag
2. Pivot points
3. Bellow arms
4. Valve bodies
5. Compressor sponge filter
6. Compressor gasket
Check:
a) Base is free from debris
b) Filter sponge position correct
c) Compressor seating
d) Electrical connections are secure and completely insulated
e) Pressure control knob is tight
f) Tubes are fully pushed on and are free from kinks
g) Tubes and electrical insulation are not damaged
h) Power switch illuminates
i) Wiring is tidy
j) Air is alternating
k) Outlet tubes and snaplock connectors are secure and fitted
correctly
4.1.1 Testing
Test the pump as given in Section 5.
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F048 4-2 Issue 3
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5 SERVICING THE PUMP
5.1 Dismantling the Pump Unit
Before dismantling the pump unit, ensure that it has been switched OFF and
isolated from the power supply by removing the electrical cord plug from the
wall outlet.
To remove the case lid, place the unit upside down on a flat, clean surface.
Remove the rubber feet and unscrew the four self tapping screws.
Holding the unit in both hands, turn it onto its base and carefully remove the lid
and place to one side.
Before the removal or replacement of the pressure control assembly, the face
label must be removed. Carefully, peel the face label from the front panel and
place to one side.
5.2 Replacing the Alarm Light LED
Carefully remove (cut OFF) insulation shrink sleeve from alarm indicator/alarm
module connectors. Separate the pin/socket connectors. Pull OFF the black
sleeve which retains the LED in the red lens. Be careful as the rectangular
mounting plate is fragile. Push the red lens out through the mounting plate.
F048 5-1 Issue 3
Mar 2003
Caution
All servicing and repair work must be performed by a trained Huntleigh
Healthcare trained service technician.

Fit a new red lens into the mounting plate from the front. Install the LED into
the lens and push on a new retaining sleeve. Put new shrink sleeves onto the
wires from the alarm module and connect the wires to the indicator by means of
the pin/socket connectors. Slide the sleeves over the connectors and the LED
wires and apply hot air to shrink in position.
The alarm light LED spare part (No. BP384) is supplied as a complete
assembly which can be stripped down as described above to replace individual
components as desired.
5.3 Replacing the Audible Alarm
To remove the faulty audible alarm, pry it OFF. If this is difficult, leave it in
place and cut OFF the connections close to the body.
Attach the new alarm to the case in the correct position (or adjacent to the faulty
unit) using a cyanoacrylate adhesive.
Reconnect the electrical wires as shown in the wiring diagram using the method
described in paragraph 5.2.
5.4 Replacing the ON/OFF Switch
To remove the on/off switch, disconnect (pull OFF) the electrical connections,
squeeze together the retaining flanges located at the top and bottom of the
switch body and push the switch through the front panel.
To replace the switch, push in from the front ensuring the switch retaining
flanges snap into position.
Reconnect the electrical connections as per the wiring diagram.
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Mar 2003