Low hot water pressure

Hi, I can help with this. The 15mm mentioned is usually the size of the water supply pipe, not the tap hole. Most kitchen taps use a much larger hole through the worktop/sink. I’d be happy to have a look at the existing setup and the new tap to make sure everything is compatible and find out why the hot water pressure is low.

Hi, the low hot water pressure is likely related to the new tap rather than the hole size alone. A 15mm bore refers to the size of the hole through the worktop/sink for the tap, but the tap also needs to be suitable for the type and pressure of your hot water system. Pull-out taps can sometimes perform poorly on low-pressure hot water systems. I’d recommend checking the tap’s minimum pressure requirements and whether your hot water supply is gravity-fed or mains pressure. If the new tap is suitable, the pipework, valves and filters should also be checked for restrictions. I’d be happy to inspect it and advise on the best solution.

Yes they might have a really small bore hole in the flexi hose, how ever in kitchen taps they nearly always have small bore holes. . Did you have decent pressure in your old tap? If so check the isolation valve is fully on. Also if it’s a combo boiler check the pressure is at around 1.5 bar.

It’s unlikely that you need a 15mm bore tap. Most modern kitchen mixer taps use 15mm flexible tails, so the tap itself is rarely the problem. Low hot water pressure is usually caused by the tap not being suitable for a low-pressure system, a partially closed isolation valve, a kinked flexible hose, or debris in the tap or cartridge. If you have a combi boiler or mains pressure, a quality tap with the correct minimum operating pressure should provide good flow. Check the tap’s pressure requirements before replacing it.

If you have bought a high pressure tap and you are on gravity hot water still then you would experience pressure drop .

Hi, low hot water pressure after fitting a pull-out spray tap is often caused by the tap itself restricting the flow, but it can also highlight an existing low-pressure hot water system. Before changing anything else, I'd check that the isolation valve under the sink is fully open and that there isn't any debris trapped in the tap's filter or aerator from the installation. If your hot water comes from a gravity-fed system or older vented cylinder, some pull-out spray taps are not suitable and can significantly reduce flow. You do not normally need a 15mm bore hole specifically to improve water pressure, so your family member may be mistaken unless they're referring to a particular tap installation requirement. If you can tell us whether you have a combi boiler, unvented cylinder, or gravity-fed hot water system, and the make/model of the new tap, we can advise more accurately.