Plumber reveals what that code on radiators REALLY mean – and how it can save you up to £180 a year on energy bills
MILLIONS of households could slash their energy bills if they understand how a simple radiator setting works.
Adjusting the numbered valves on the ends of your radiators could save a fortune this winter.
These clever devices are known as thermostatic radiator valves (TRVs).
TRVs function by regulating the flow of hot water from your boiler into your radiator.
This can help reduce the amount of gas your boiler needs to burn to heat your central heating system – but only when they’re used correctly.
The Sun spoke to Rob Nezard, plumber and managing director of UKRadiators.com, to find out exactly what those numbers on our TRVs really mean.
Rob said one of the most common questions that he gets asked as a plumber is: “What do the numbers on a thermostatic radiator valves mean?”
Many people mistakenly believe these numbers reflect the radiator’s temperature.
In reality, they are entirely related to the room’s temperature.
Rob said: “TRVs have clever mechanisms, sometimes using liquid or wax, that will shut off the flow of hot water to an individual radiator when the room temperature is at its desired level.
“Installing thermostatic radiator valves is like having a boiler thermostat control in every room without interacting with the boiler directly.
“The numbers on the TRV typically range from 1 to 5 or 6, and most also have a frost symbol – this indicates that the TRV is in frost protection mode.”
This crucial function prevents pipes and radiators in unused rooms from freezing, thereby protecting your heating system and home.
However, the whole point of a TRV is to detect the temperature of a room and then control how much hot water is let into the radiator.
If the room is cold, the TRV will sense this and allow more hot water to enter the radiator to heat it quickly.
As the room warms, the TRV will restrict the hot water flow to maintain the desired temperature.
When the room temperature drops, the TRV will again allow more hot water in, repeating the cycle.
Rob said that the number settings on a TRV roughly correspond to the room temperatures below:
- 0 = 0°C (off)
- ✱ = 5°C (usually shown as a snowflake or full stop symbol)
- 1 = 12°C
- 2 = 16°C
- 3 = 20°C
- 4 = 24°C
- 5 = 28°C
- 6 = 32°C
Rob added: “TRVs give you total control of your heating, meaning you don’t need to heat rooms you aren’t using, and they are designed to switch off when they reach the right temperature.
“Savings are estimated at between £55 and £180 per year for a typical three-bed semi.”
How much can you save with TRVs
THE average household can save up to £180 a year if they have thermostatic radiator valves fitted on all their radiators, according to Energy Saving Trust.
Valves can be picked up for less than £8 and they’re easy to replace yourself if some of yours are not working.
Households can also get their hands on smart TRVs, which can be controlled via an app, but these are more expensive, with prices starting at £39 from Screwfix.
What numbers should I set my TRVs to?
During the winter months, Rob recommends that households to set their TRV to 2 or 3 in smaller rooms.
Those going away this winter should keep their radiator TRV on the lowest setting so that the radiators will come on for a short while if the temperature drops below 7°C.
However, Rob warned against turning your TRVs to five.
This is because you are telling the boiler not to stop letting hot water into the radiator until the room reaches a very high temperature (around 30°C).
Households should only have TRVs on five or their maximum setting in rooms requiring short and sharp heat.
How else can I cut my heating bills?
If you turn your boiler’s flow temperature down you could save around £180 annually on your energy bills.
A couple managed to cut £400 off their EDF Energy bill by turning off their immersion heater.
Topping up loft insulation and switching to a smart meter can also bring a household further savings.
Reducing draughts and heat loss will also help to cut your heating costs so grab some draught excluders and consider increasing your insulation.
It’s also important to consider which rooms in your home need heating.
You won’t be using each one 24/7, so ensure the heating is set to frost protection in any rooms that aren’t occupied.
There is also a list of other common boiler problems we’ve rounded up that could be pumping up your bills.
What energy bill help is available?
There's a number of different ways to get help paying your energy bills if you're struggling to get by.
If you fall into debt, you can always approach your supplier to see if they can put you on a repayment plan before putting you on a prepayment meter.
This involves paying off what you owe in instalments over a set period.
If your supplier offers you a repayment plan you don’t think you can afford, speak to them again to see if you can negotiate a better deal.
Several energy firms have grant schemes available to customers struggling to cover their bills.
But eligibility criteria vary depending on the supplier and the amount you can get depends on your financial circumstances.
For example, British Gas or Scottish Gas customers struggling to pay their energy bills can get grants worth up to £2,000.
British Gas also offers help via its British Gas Energy Trust and Individuals Family Fund.
You don’t need to be a British Gas customer to apply for the second fund.
EDF, E.ON, Octopus Energy and Scottish Power all offer grants to struggling customers too.
Thousands of vulnerable households are missing out on extra help and protections by not signing up to the Priority Services Register (PSR).
The service helps support vulnerable households, such as those who are elderly or ill, and some of the perks include being given advance warning of blackouts, free gas safety checks and extra support if you’re struggling.
Get in touch with your energy firm to see if you can apply.