Salamander CT50 Xtra 1.5 Bar Twin Positive Head Shower Pump

In-Depth Look

The Salamander CT50 Xtra is the shower pump that UK plumbers reach for when a customer complains about poor shower pressure in a gravity-fed property. It has earned its reputation through years of reliable service across thousands of UK installations.

Positive Head: Understanding the Requirement

The CT50 Xtra is a positive head pump, which means it requires a gravity feed from the cold water storage tank to activate. The water outlet from the tank must be at least 300mm above the pump inlet for positive head operation to work correctly. In properties with a loft-mounted cold water tank, this is typically straightforward. In properties where the tank and pump are on the same floor level, a negative head pump (such as the Salamander CT50+ Xtra) is required instead. Specifying the correct type for the installation is the single most important consideration.

Twin-Ended Design

The twin impeller design is the key advantage of the CT50 over single-ended pumps. By boosting both hot and cold supplies simultaneously, it delivers balanced pressure to thermostatic shower valves, preventing the temperature fluctuations that occur when only one supply is boosted. Single-ended pumps are only appropriate where the cold supply is mains-pressure and only the hot needs boosting.

Installation Considerations

With 22mm push-fit connections, the CT50 Xtra installs directly onto 22mm pipework without additional fittings. Anti-vibration feet and the quiet motor design allow installation in an airing cupboard or loft space close to living areas. WRAS approval means the pump has been assessed as suitable for connection to the UK water supply under the Water Fittings Regulations. It does not cover the installation itself, which should still be done correctly, ideally by a qualified plumber.

Selecting the Correct Size

Salamander produce the CT50 (1.5 bar), CT75 (2.2 bar), and CT100 (3.0 bar) variants. The CT50 suits most standard gravity-fed showers. Where the gravity head is very low or the shower demand is high (large rainfall heads or multi-outlet systems), the CT75 is the better specification.

Verdict

The Salamander CT50 Xtra is the reliable, proven choice for boosting shower pressure in positive head gravity-fed systems. Its WRAS approval, twin-ended design, and quiet operation make it the pump that plumbers specify with confidence.

How It Compares

The Salamander CT50 Xtra is a twin-ended, positive head shower pump, which means it boosts both the hot and cold water feeding a shower and only works where water arrives by gravity from a storage tank. It is designed to fix weak pressure in tank-fed homes, and it is one of the best-known pumps of its type in the UK.

Within Salamander’s own range, the file names the CT50 (1.5 bar), CT75 (2.2 bar) and CT100 (3.0 bar). The CT50 suits most standard gravity-fed showers, while the CT75 is the better specification where gravity head is very low or demand is high, such as large rainfall heads or multi-outlet systems. The negative head equivalent, the CT50+ Xtra, is for installations where the tank and pump are on the same level.

Other well-known makers include Stuart Turner, whose Monsoon range is familiar to plumbers, as well as Grundfos and Mira. All of these sell several pump types, and the specifications differ by model, so compare the pressure, the head requirement and the connection type on the exact product you are considering.

The CT50 Xtra’s strengths, from the file, are WRAS approval, quiet running with anti-vibration feet, and 22mm push-fit connections that install directly onto 22mm pipework. The drawbacks are that it needs a minimum gravity head to start and that 15mm pipework needs adaptors.

The practical test is simple. If your hot and cold both come from tanks above the pump, a twin-ended positive head pump is likely correct. If your cold is from the mains, you need a different arrangement. A plumber can confirm which fits.

Common Questions

Can I use a positive head pump with a combi boiler? Generally no. A standard twin positive head pump is designed for tank-fed hot and cold supplies, while a combi boiler is fed from the mains and has no tank. Pumps for mains-fed systems are different products, so speak to the manufacturer or a plumber before buying. Do not simply connect a tank-fed pump to a mains supply.

Why does the shower pump need a cold tank in the loft? A positive head pump relies on gravity to feed water to it. The file states the water outlet from the tank must be at least 300mm above the pump inlet. A loft tank usually provides that height. Without enough head, the pump may not start or run correctly, which is why the type and position matter more than anything else.

Can it feed a bath tap as well as the shower? The CT50 Xtra is described as a shower pump, and a bath tap draws far more water than a shower, so do not assume it can feed one. Check Salamander’s instructions for which outlets the pump is approved for, and ask a plumber if you want a boosted bath fill. For a high-demand shower, such as a large rainfall head or several outlets, the product file points towards the more powerful CT75.

Why is my pump noisy or cutting in and out? Possible causes include air in the system, a low water level in the tank, a partly closed valve or a restriction in the pipework. Check that the pump is fixed on a firm surface using its anti-vibration feet and that connections are sound. If the problem continues, check the manual and contact Salamander or a plumber rather than tampering with the pump.