A Guide to Dual Fuel Heated Towel Rails

Dual fuel heated towel rails are a great idea for bathrooms that remain a little chilly throughout the year.  A dual fuel towel rail is part of your central heating system but also features an internal electric heating element. This allows the rail to work independently from the rest of the house, giving you warm, dry towels in the summer without having to turn on your entire boiler system.

Buying a Dual Fuel Towel Rail

A wide range of towel rails can be converted to dual fuel by using a dual fuel kit.  

To select the right dual fuel kit for a towel rail:

Choose a Valve
All towel rails require valves, as they control the amount of hot water that enters and leaves the towel rail, regulating the heat that the towel rail can generate. Alongside a pair of standard valves, for dual fuel installations, a T Piece is also required. This allows both an element and a valve to be fitted to the same connection on a towel rail. Alternatively, there are Dual Fuel TRV valves available, which incorporate a TRV, Lockshield and an integrated T Piece to accommodate the element, for a neater finish.

Choosing the Right Element Size

Radiator heating elements slot into the towel rail and heat it using mains electricity. Choosing the correct wattage for your element is vital. If it's too small, the rail won't heat up; if it's too large, the element could burn out prematurely.

As guidance, the following chart shows the towel rail output in watts and the corresponding recommended size of the element.

If you are unsure of the wattage of the towel rail but know the BTU, the wattage can be calculated by dividing the BTU by 3.41.

Dual fuel towel rails are fitted just like standard ones. They need to be plumbed in and hung on the wall. The only difference is that you’ll also need a fused spur near the entry valve.  A certified electrician may need to do this and have the work signed off for Building Regulations.  In fact, the installation of any electric dual fuel towel rail should ideally be left to a professional, as there are a number of regulations in place that cover working with water and electricity in close proximity.

Usage

Dual fuel towel rails are designed to run as part of a central heating system or from mains electric; they can’t do both at the same time.

To run a dual fuel towel rail as part of the central heating system:

1. Ensure the heating element is turned off
2. Check the bleed valve/air vent is closed tight
3. Turn the inlet and outlet valves on

To run a dual fuel towel rail from mains electric:

1. Ensure the inlet and outlet valves are completely off, isolating the towel rail from the central heating system.
2. To avoid pressure building up in the towel rail, slightly loosen the air vent.
3. Only then turn the heating element on

Dual fuel towel rails offer a household the most economical way of heating a room in both the winter and summer months.  For our range of dual fuel towel rails, see here.

FAQs

Can I leave the valves open when using the electric element?

No, you must close both valves when using the electric element. If the valves are open, the heat from the electric element will escape into the rest of your pipework, making it extremely inefficient and potentially preventing the towel rail from getting warm.

Do I need an electrician to install a dual fuel towel rail? 

Yes, you must use a qualified electrician to wire the heating element into a fused spur. Because this installation involves water and electricity in proximity (usually in a bathroom), it must comply with Part P Building Regulations.

Can any towel rail be converted to dual fuel?

Most standard plumbed towel rails can be converted to dual fuel using a T-piece and a compatible heating element. However, some very slim or uniquely shaped designer rails may not have the internal clearance required for a standard heating rod.

Do I need to bleed a dual-fuel towel rail?

Yes, just like a standard radiator, air can become trapped at the top of the rail. You should bleed it regularly during the winter. When using the electric mode in summer, slightly loosening the bleed valve is recommended to allow for water expansion as it heats.