Huntleigh AlphaBed, Service Manual

Page: 71 / 94

2.3 If the alarm still indicates, visually inspect tubing and mattress cells for punctures or tears and
check they are fitted to the manifold correctly. Refer to the mattress service manual SER0005
for full details.
WARNING:
DANGER OF ELECTRIC SHOCK. DURING THE FOLLOWING TESTS, LIVE
TERMINALS AND CONDUCTORS MAY BE EXPOSED. EXERCISE EXTREME
CAUTION.
3 Loss of Output Pressure (checks by dismantling the pump)
If the low pressure alarm operates when both pump outlets are blocked or the pump does not pass
the flow test in Chapter 5 (Testing), the pump unit internal compressor should be tested as follows:
3.1 Remove the rear case (Refer to Chap 3, Page 5).
3.2 Disconnect the white pneumatic tube from the compressor F-Tube connector.
3.3 Connect the pressure gauge to the compressor F-Tube connector and switch the pump unit on.
The pressure reading should be at least 100 mmHg.
3.4 If the pressure does not reach 100 mmHg, the compressor is at fault. Either replace the
compressor or 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 should be approximately
100 mmHg in each case. (Refer to Chap 3, Section 22).
3.5 If the required pressure cannot be reached then the bellows/armature assemblies and valve
bodies must be replaced (Refer to Chap 3, Section 23). If the required pressure is obtained
then the silencer bag must be replaced. (Refer to Chap 3, Section 22).
Note : The flow/pressure performance of a compressor may be altered by heating the new bellows
and adjusting the ‘E’ stack gap.
3.6 If the compressor is operating correctly but the correct pressure cannot be obtained at the
pump outlet then the rotor/stator, pressure control module and snap-lock connectors must be
checked. Reassemble the compressor and attach pressure rig to pump outlet again.
3.7 Remove the gearbox and rotor/stator, clean all dust off rotor/stator and reassemble with new
gasket. If rotor/stator is chipped or damaged, replace components (Refer to Chap 3, Section
37). If this does not correct the problem, check the pressure control.
3.8 Push on the pressure control flap (Fig 19, Item 20) to press the seal (Fig 19, Item 70) against
the valve seat. Check the pressure control bag inflates fully and pushes on the flap, if not, the
bag could be split - check and replace as necessary.
3.9 If the snap-lock connectors or tubing show signs of damage, replace. If there is still a problem,
re-check in the following order:
•
compressor
•
rotor/stator assembly
•
pressure control assembly
•
connections
If pressure/flow still cannot be achieved, return pump to Service department.
Issue 2 Chap 4
Nov 2001 SER0004 Page 3
Mini Pump Service Manual Troubleshooting