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Description
If the hot supply to one shower or tap on your unvented system goes weak when other taps are run, then the SP2B is the best pump for you. If both hot and cold suffer, the SP22S is the pump for you.
An unvented cylinder — Megaflow is the name most people know, but it’s the same for Main, Telford or any brand, are supposed to be the fix for weak showers. But it can only pass on the pressure the mains gives it, and when other taps and toilets share that supply, your shower still fades at the worst moments. Thousands of homes paid for a pressurised system and still queue for the shower.
Whilst you may have been told nothing can be fitted to a sealed system, the Shower Power Booster can be fitted, it is the only pump designed specifically to work with unvented systems.
Fit the SP2B on the dedicated branch pipe feeding only that specific tap or shower — hot side, cold side, or wherever the pressure drop occurs — and it boosts the pressure and protects the flow when the rest of the house is drawing water. It detects flow and starts by itself — no switches, nothing to turn on — runs on safe 12 volts, and carries WRAS approval: the UK’s independent verification that it’s safe to fit to your home’s water supply, sealed systems included.
Q: Is it really safe to fit a pump to an unvented system? A: Yes — the SP2B is the only pump designed for unvented systems, and it’s WRAS approved. Fitting it on a dedicated branch doesn’t interfere with the cylinder’s safety controls.
Q: Hot side or cold side? A: Wherever the weakness shows. If the hot taps are the problem, boost the hot; if the shower loses cold when a toilet fills, boost the cold. One pump per problem pipe.
Q: What if the whole house is low, not one outlet? A: That’s the SP21S — fitted to the incoming supply, or one pump either side of the cylinder. See the SP21S unvented page.
Fit the SP2B the dedicated branch pipe feeding only that specific tap or shower. Not sure exactly where to position the pump? Run the shower and see what pipe gets hot.