I am a maintenance tech for a business and I am having an issue I hope you can help with.
We have a men's and women's restroom that are back to back, (sharing the same drain) with 3 sinks in each. One of the sinks in each of the rooms, the most popular, drains very slowly. I have used drano max, liquid plummer gel and some generic acid brand and still the drain does not improve. There is nothing physically blocking the drain such as hair. I have called out a plummer in the past and was told it is the type of soap our janitorial supply uses that causes this. He said there was nothing he could really do and that I should get in the habit of pouring hot water down the drains regularly to help break up the soap. I have tried this as well as everything listed above with little or no improvement. Any other suggestions?