sure they will.
provided you can show it was installed correctly 20 years ago.
and you can't coz you will be living somewhere else, not knowing who installed it.
the biggest problem with plastic pipe and push fit, which is why i personally am not keen on them, is they're more often than not installed wrong. for example most of the time plastic pipe doesn't have inserts fitted, the ends aren't cut very well, the collet clips are missing, pipework is bent all over the place putting excess strain on connections and they don't normally screw it tight.
a couple of days ago i had to cut a hole in a ceiling because the fitting was only held in place by the tightness of the pipe and it had never been screwed up so had leaked for the 2 years it'd been installed - system lost pressure all the time. when i replaced that fitting the one next to it leaked just because i'd move th pipe about.
If you need to find a tradesperson to get your job done, please try our local search below,
or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Please select a service and enter a location to continue...
Are you a trade or supplier? You can create your listing free at DIYnot Local