Meiko K-Tronic Service Manual page 84

Detergent detection
with fluid pH
1.3.3
Carrying out:
· Put a few drops of the indicator solution 3 (phenolphthalein) on the surface to be proofed
· If it clearly turns red, soapy water residue is present (pH > 7)
Important:
Softened water occasionally leads to a slight reddening.
This does not mean that soapy water residue is present.
Note:
· Detergent dissolves under flowing water
· In case of detergent containing chlorine = chlorine odor
1_3_3_Detergent detection Update: 03.09.2002