Very slow drainage of a small bathroom sink. Liquid Plumber does not help

A professional plumber.

ring around plumber whole sale suppliers and explain what you want
they are in a position to advise you where or if what you want is still available

If the new pipe was not tied into the vent it would cause this problem.

You may have to call a professional or, if it were me having this problem, I would keep trying the Liquid Plumber or even Drano. I have found that the foam versions work best, but you may have to try it more than once. In a 14 year old building that has never had plumbing done, there could be a really bad clog that only a professional can handle. I hope this helps.

Yes The Blanko is installed with silicon not plumber putty. This is common with the newer sink strainers


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Yes - This is an easy (though not widely known) diy fix! Remove the cover of the faucet handle (may pop off if crystal type or use a screwdriver to remove the screws) inside there is a scald guard safety mechanism - using a flathead screwdriver, turn the guard some the left. There should be a guide so that you do not turn the water up too hot. If there is not, you may need to consult a plumber or supplier in order to adjust the hot to a moderate temperature.

Hope this helps! ;)

you have air in the water lines try going to your water heater and lift the pressure relief vavle slow hold open have hot water valve on sink on let water run till water comes out pressure releif vavle make sure water heater is off and cool first

soak it in hot water and try pumping it every so often,should loosen liquid soap.

have the plumber pop an opening on the side of the drain pipe under the sink. and add a indoor vent.

You are describing a problem known as water hammer. This will ultimately cause damage somewhere in your plumbing system so it should be addressed. If you are handy you can install an air chamber near the sink. If you want more information let me know. good luck.