Mine is a stainless steel Kitchen Aid and the way the warning light works is similar to yours. I just press and hold the light button to reset it to green. It works every time. I believe it is based on time and not based on flow rate. I might be wrong but I cannot see any damage can be done. The call for water switch activates an on/off valve that allows the water to flow thru the filter. If you do not see any restriction in flow then everything is OK.

I would just reset it.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
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1 x 87 300TDT wagon
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