User Guide

Instruction Manual DO 100

9.3 Membrane Housing Replacement

Replacement of the membrane cap housing/ membrane is

required only when you cannot calibrate the probe, or if the

membrane is damaged.

Typical membrane damages are punctures or wrinkles

caused during measurements or cleaning. For more

information see trouble-shooting guides in sections 9.6 and

10.

Your new DO probe comes with a replacement membrane

housing. To order more replacement membrane housing,

see the “Accessories” section on page 52.

9.3.1 To replace the membrane cap (with pre-

installed membrane) -

Replacement is much easier with single membrane housing.

Simply unscrew the old membrane cap housing, add solution

to the new housing, and screw the new cap housing in place.

1. Fill the membrane cap housing with electrolyte solution

and inspect the bottom for leaks. If the solution drops

are leaking from the membrane, use a new cap

housing.

2. If the assembly is leak-free, fill the membrane cap

housing with electrolyte to the brim.

3. Tap the side of the housing gently to remove any air

bubble that may be sticking to the membrane.

4. Screw the cap onto the probe. Excess electrolyte will

drain out.

5. Replace probe guard.

6. Calibrate the probe (see section 4) after the %

saturation readings have stabilised.

Figure 33: Positioning of O-ring

& membrane