How to Check Your Water Pressure System Before Choosing a Kitchen Tap

Choosing a new kitchen tap can sometimes feel more complicated than expected. Many customers find themselves faced with questions about minimum pressure requirements, high pressure systems, low pressure kitchen taps, and whether their home water system is suitable for the tap they want to install.

The most important thing to understand is that not every kitchen tap works correctly on every plumbing system.

If your existing kitchen tap has poor hot water flow, takes a long time to fill a kettle, or you are replacing your tap and want to avoid choosing the wrong model, the first step is to identify what type of water system you have.

One of the most common systems found in UK homes is a traditional gravity fed hot water system.

What Is a Gravity Fed Water System?

A gravity fed system uses gravity to create water pressure rather than a pump or mains pressure.

Typically, this system consists of:

• A cold water storage tank (usually located in the loft)
• A hot water cylinder (normally found in an airing cupboard)
• Hot water supplied to your kitchen tap from the cylinder using gravity

The higher the cold water tank is positioned above your kitchen tap, the greater the pressure available.

The lower the height difference, the lower your water pressure will be.

Step 1: Check If You Have a Cold Water Storage Tank

The first thing to look for is a cold water storage tank.

In most houses, this will be:

• Located in the loft space
• Positioned on a raised platform or wooden frame
• Usually made from plastic

If you live in an apartment or a property without a traditional loft, the tank may be positioned above the hot water cylinder in a cupboard or service area.

Once you locate the tank, measure the distance between:

The bottom of the cold water storage tank and the point where your kitchen tap is installed.

This measurement will be needed to calculate your approximate water pressure.

Step 2: Confirm You Have a Traditional Hot Water Cylinder

The next step is to locate your hot water cylinder.

This is usually found in:

• An airing cupboard
• A storage cupboard
• A utility area

A traditional cylinder is often surrounded by stored bedding and towels, but the important thing to check is whether it has been modified.

Look above the cylinder.

If you see a small round pressure vessel or expansion tank, you may have a pressurised unvented hot water cylinder instead.

An unvented cylinder operates differently and usually provides a much higher pressure system. In this situation, you generally will not require a low pressure kitchen tap.

Step 3: Calculate Your Kitchen Tap Water Pressure

Once you have confirmed you have a gravity fed system, you can estimate your available hot water pressure.

Water pressure is measured in Bar.

As a general guide:

Every 1 metre of height creates approximately 0.1 Bar pressure.

For example:

• Height from kitchen tap to ceiling: 1.2m
• Height from ground floor to first floor: 2.4m
• Height from loft floor to bottom of cold water tank: 1.0m

Total height:

1.2m + 2.4m + 1.0m = 4.6 metres

Therefore:

4.6 metres = approximately 0.46 Bar pressure

Allow for Pipework Restrictions

The calculated pressure is not the final pressure your kitchen tap will experience.

The actual flow can be affected by:

• The length of pipework between your hot water cylinder and kitchen tap
• The number of bends in the pipe
• Older pipe installations
• Restrictions within valves or connections

For this reason, we recommend allowing a small reduction from your calculated figure.

A simple guide is to remove around 10%.

Using the example above:

0.46 Bar minus 10%

= approximately 0.4 Bar available pressure

Choosing the Correct Kitchen Tap for a Low Pressure System

Once you know your approximate pressure, you can choose a kitchen tap with the correct minimum pressure requirement.

Every kitchen tap should have a stated minimum operating pressure.

For example:

• Your system pressure = 0.4 Bar
• Tap A requires minimum 0.4 Bar
• Tap B requires minimum 0.2 Bar

Both taps may work, but Tap B is likely to provide better performance because it is designed to operate effectively at lower pressure.

The lower the minimum pressure requirement, the better suited the tap is for a gravity fed system.

What Are the Best Kitchen Taps for Low Pressure Systems?

If you have a gravity fed system, look for:

✔ Kitchen taps with a minimum pressure of 0.2 Bar or lower
✔ Traditional bridge taps designed for gravity systems
✔ Twin lever kitchen taps
✔ Low pressure compatible monobloc taps

Be careful with:

✘ Pull-out spray taps
✘ Water filter taps
✘ Some modern single lever mixer taps

These products often require higher pressure because of internal restrictions, spray functions, and flow control technology.

Frequently Asked Questions

How do I know if I have a low pressure water system?

A low pressure system usually has a cold water storage tank in the loft and a hot water cylinder in an airing cupboard. The height between the storage tank and kitchen tap determines the available pressure.

What pressure does my kitchen tap need?

This depends on your plumbing system. Many modern kitchen taps require around 0.5 Bar or more, but gravity fed systems may operate below this. Always check the manufacturer's minimum pressure requirement before buying.

Can I install any kitchen tap on a gravity fed system?

No. Some kitchen taps require higher pressure than gravity systems can provide. Choosing a tap designed for low pressure will ensure better hot water flow and performance.

Why does my hot water tap have low flow but my cold water is fine?

This is commonly caused by a gravity fed hot water system where the hot water pressure is much lower than the mains cold water pressure.

Can I fit a pull-out spray tap on a low pressure system?

Some pull-out spray taps require more pressure than a gravity fed system provides. Always check the minimum pressure specification before installation.

Find the Right Low Pressure Kitchen Tap

At Taps Online, we offer a wide range of kitchen taps designed for different plumbing systems, including models suitable for low pressure and gravity fed hot water systems.

Before purchasing, always check your home's water pressure and the tap's minimum pressure requirement to ensure the best possible performance.