Noise is a real factor when deciding between the two. A side-entry valve introducing water above the surface tends to produce more splash and a higher-pitched fill sound, which shows up as a complaint on quieter properties such as flats with shared walls. Bottom-entry valves that fill below the surface are noticeably quieter, and swapping a noisy side-entry unit for a bottom-entry equivalent is a common upgrade even where nothing has technically failed.

Get the wrong flush valve on a low-level system and the flush pipe will not seat properly, leading to leaks at the joint that only show up once the cistern has been refitted and the access panel closed up again. Get a close-coupled flush valve into a low-level tank and the outlet is simply too short to reach the flush pipe collar at all.

Plumb2U stocks side levers, lid-mounted levers and the link arms and clips that connect them to flush valves and siphons, priced for trade buyers ordering more than one at a time. For a plumber working through several lever jobs a week, having a trade supplies merchant that lists the fitting details clearly rather than a single generic photo makes the difference between one van visit and two. Plumb2U, trading from Epsom but supplying trade accounts UK-wide, carries a lever range that covers most of what turns up on a round.

A side-entry fill valve takes its supply through the side wall of the cistern, typically a few centimetres up from the base, with the water pipe running horizontally into the tank. This is the older and still very common arrangement in UK homes, particularly where the supply pipe rises through a wall cavity or runs along a skirting board before turning up into the cistern. Side-entry valves are usually the easier option where floor space beneath the cistern is tight, since there is no need for the pipe to come straight up from below.

For trade buyers stocking a van, the sensible approach is universal fill and flush valves as the default stock, with brand-specific buy plumbing parts online ordered against a specific job once the cistern or frame has been identified on site rather than guessed at from memory. Plumb2U carries a wide universal range alongside brand-matched fill valves, flush valves and flush plates for the less common cistern designs, at trade prices, which means a plumber can order the specific part for an awkward job without paying retail elsewhere. Operating as a trade supplies merchant from its Epsom base, Plumb2U notes stock detail on each product, making it easier to tell which category a given job falls into before the part is added to the basket.

You can find out more via flexible hose supplier.