I had a hot tap valve replaced and the plumber used oil to free the stuck valve.
The oil looked just like car engine oil and I am worried it may have contaminated my water supply.surely a plumber would not use car oil in a domestic water supply
Can anyone give me an idea what should be used to do the job.
Thanks

You won't contaminate the system, it is under pressure and the stem is out of the water stream. Without seeing it you can never tell if it was motor oil. Even plumbers grease is petroleum based.

You can not contaminate the water system by putting oil on the outside of pipes or valves. General oil, may look like a motor oil.

Not sure what your plumber used to free the stuck valve - but the "oil" he used should not contaminate your water at all.

I serious doubt a plumber would carry motor oil in his tool bag, most likely plumbers grease which will not be a problem

May be the plumber used some kind of oil foe lubricating the stuck valve am agree with all the experts above that it will not contaminate your water supply, Thanks.

John

Fully agree with Ballengerb's suggestion. Plumbers usually don't carry motor oil in their tool box. At least I have never seen one. Plumber's grease is dark and looks like bearing grease.

Even if some of the lubricant he used got into your water pipe, it would get flushed out first time you used the faucet. If you smell "oil" in your water, open faucet for few minutes and water flow should flush it out.

But in any case, it is nothing to be alarmed of.

Milo