Invacare Platinum IRC5LXAW Service Manual page 22

SECTION 4—TROUBLESHOOTING
SYMPTOM
Low Concentration
(Continued)
Fluctuating Flow
Platinum™Oxygen
PROBABLE CAUSE
P.C. board:
a. Shifts at wrong pressures.
Flowmeter:
a. Flowmeter opened beyond
maximum flow rate.
b. Cracked or broken fitting.
c. Input tubing leaking or loose.
Timing.
P.E. valve:
a. Bad coil.
b. Restrictor blockage.
Inspect P.C. board restrictor tubing for
kinks or tears.
Regulator/Flowmeter:
a. Incorrectly set regulator.
b. Flowmeter malfunction.
Outlet HEPA filter:
a. Dirty or plugged
Check pressure at product tank. Pressure
should rise to 144.79 kPa (21 psi) at shift
point. If not, replace P.C. Board. Refer to
Replacing P.C. Board on page 63.
a. Return flow to maximum setting.
b. Replace fitting.
c. Repair or replace. Refer to Replacing
Flowmeter on page 67.
To accommodate for varying tolerances
when replacing components, an adjustable
timer is used to control the shifting of the
Pressure Equalization (P.E.) valve. Refer to
Timing on page 81.
a. Replace P.E. valve.
b. Replace P.E. valve. Refer to Replacing
P.E. Valve on page 48.
Replace P.C. board. Unit may need retiming
after board replacement. Refer to Replacing
P.C. Board on page 63.
a. Check pressure at oxygen outlet.
Adjust regulator.
b. If flow is still unstable, check for leaks
starting at the compressor outlet
fitting through all pneumatic
connections. If no leaks are found and
flow is still fluctuating, replace the
regulator. If pressure at test point is
within spec 34.4 kPa ± 6.89 (5 p.s.i. ±
0.2 max.), replace flowmeter. Refer
to Replacing Flowmeter on page 67.
a. If low flow conditions persist, replace
outlet HEPA filter. Refer to Replacing
the Outlet HEPA Filter on page 28.
22
SOLUTION
Part No 1118396