Hot Water Tank Replacement – When, Why & How to Upgrade

New unvented hot water cylinder installed in airing cupboard

Time to Replace Your Hot Water Tank? Here’s What to Know

Your hot water tank works hard behind the scenes — supplying hot water to taps, showers, and appliances throughout your home or business. But like any system, it won’t last forever.

At Lucas Plumbing & Heating Ltd, we replace hot water tanks across Berkshire, including Wokingham, Reading, Ascot, and surrounding areas. Whether you’ve got an unvented cylinder, a copper vented tank, or a commercial thermal store, we’ll help you upgrade safely and efficiently.

Signs You Need a Hot Water Tank Replacement

Not sure if your tank needs replacing? Here are the most common warning signs:

1. Leaks or Rusting

Corrosion on the outside of the cylinder or water pooling underneath the tank are serious signs of internal failure. If left unchecked, leaks can cause major water damage.

2. Low Hot Water Pressure

If your taps or shower have weak flow or take ages to heat up, your tank could be blocked with scale or sediment — especially in hard water areas.

3. Discoloured or Smelly Water

A rusty or metallic smell often means the tank lining is breaking down. In copper tanks, green-tinged water is another indicator.

4. Inconsistent Water Temperature

Does the water go hot, then cold? Your immersion heater, thermostat, or cylinder coil may be failing — or the tank insulation could be degrading.

5. System Over 10–15 Years Old

Most hot water tanks last around 10–15 years. If yours is older, it's more likely to develop faults, become inefficient, or fail compliance with modern building regulations.

Types of Hot Water Tanks We Replace

At Lucas Plumbing & Heating Ltd, we work with all major hot water systems:

Vented Hot Water Cylinders

Traditional copper tanks, fed from a cold-water storage tank in the loft. Still common in older homes and flats.

Unvented Hot Water Cylinders (Pressurised)

Modern mains-fed tanks offering better pressure and no need for loft tanks. Ideal for larger homes and new builds.

Thermal Stores

Heat water using energy from multiple sources (e.g., boilers, solar, or wood burners) with a blending valve for safe delivery.

Commercial Hot Water Cylinders

High-capacity stainless steel cylinders used in hotels, schools, gyms, and care homes.

Our Replacement Process

When you book a hot water tank replacement with Lucas Plumbing & Heating Ltd, here’s what to expect:

Site Survey & Assessment
We assess the size, condition, and setup of your existing tank and discuss your needs — including cylinder size, type, and usage.
Old Tank Removal
We safely drain, disconnect, and remove the existing cylinder, ensuring minimal disruption to your property.
Installation of New Tank
We install your new hot water tank (vented or unvented) with all required pipework, valves, insulation, and safety features.
Commissioning & Testing
We ensure the system is correctly filled, vented, and functioning — including pressure tests and thermostat calibration.
Disposal of Old Cylinder
We responsibly remove and recycle your old tank to ensure a clean and safe finish.

Ideal Time to Replace a Hot Water Tank

During a boiler upgrade
As part of a loft or airing cupboard renovation
If you’re experiencing low pressure or running out of hot water regularly
After detecting leaks or rust during a service

How Much Does It Cost to Replace a Hot Water Tank?

Cylinder TypeTypical Installed CostVented (copper) tank£550 – £850Unvented 150–250L£850 – £1,400Thermal store cylinder£1,200 – £2,000Commercial hot water tank£1,800 – £5,000+