Cartride for lever sink mixer.

A question for all the plumbers.

about 3 years ago I put a dorf KYTIN double lever sink mixer (goosneck) in the new kitchen.

Its starting to drip. the cause is that we have too high a pressure. I have a reduction valve but well its been sitting there for 2 years and I haven't gotten around to it yet:-

anyway it looks to me as this tap doesnt have washers, just cartridges..one for hot and one for cold. I'm told they are $90 each to replace by Mr Dorf but the are covered by a 4 year warranty.

being self employed I keep all receipts......yep you guessed it...nowhere to be found!

I've decided not to fit the pressure reduction valve as I am going to run irrigation at the top of my steep block and this is the only mixer tap. I am not however going to shell out $180 everytime it wants to leak, soooooo

Anyone got a source cheaper than $90?
If I replace it are there mixer taps that will handle decent pressure?
Can I repair the cartridge IE is there a washer inside or on the outside of it that is replaceable?

Thanks in advance.


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