Perform Diaphragm Leak Test; Balancing Chamber Diaphragm Leak Test Theory - Fresenius Medical Care 2008T Troubleshooting Manual

Yes FPOS more than 7000! See procedure number
No FPOS less than 7000. Proceed to
Flow Pump.
BC LEAK- 3.2.0 PERFORM DIAPHRAGM LEAK TEST
WITHOUT LOOKING AWAY, NOW watch FPRE for up to three (3) minutes. Does it EVER, even if only
once, increase or fluctuate to MORE THAN four thousand (4000)?
Yes FPRE fluctuates to 4000 or more! A torn balancing chamber diaphragm is indicated. Remove the
clamp from valve #29 then replace BOTH balancing chamber diaphragms.
No FPRE remains ALWAYS approximately 2300! See parts a AND b below:
a) A torn diaphragm is NOT indicated!
return the dialyzer lines to the shunt!
b). If referred to TESTING FOR A LEAKING BALANCING CHAMBER DIAPHRAGM, return to the
procedure that brought you here as NOTED!
Balancing Chamber Diaphragm Leak Test Theory: Referring to the Figure below, the Flow Pump #21
delivers a highly conductive acid solution into the 'spent' (S) side of the balancing chambers at high pressure.
Both balancing chamber 'fresh' (F) sides are open to low pressure because the blue (to dialyzer connector)
line is in a bucket open to atmosphere. If a balancing chamber diaphragm is torn (right side in this case) the
conductive acid solution is forced through the hole, into the fresh side, through Conductivity Cell #7 causing
FPRE to increase. If neither diaphragm is torn they prevent the acid solution from entering the fresh side and
FPRE will not increase. Recirc valve #29 must be clamped to prevent its eventual opening from recirculating
the acid solution back into the hydrochamber causing FPRE to increase falsely.
page 580
, procedure number
IMPORTANT!
2008T Troubleshooting Guide
P/N 490292 Rev. A
BC LEAK- 3.2.0 (page 584).
BC LEAK- 1.1.0
Remove the clamp from valve #29 and
to check the
Page 584