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    Don't buy a new boiler before reading this article!

    January 12, 2022
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    Shall I buy a new boiler?

    Don't buy a new boiler before reading this article!


    "Shall I buy a new boiler?" this is the first question we get when customers come to us to replace their old boiler. An old boiler can fail to keep the water and rooms warm enough, and also they can cause more energy usage and lead you to waste money. In this article, we will explain to you when you will need to replace a new boiler. You can check a few points then decide either you need a new boiler or service your old boiler. 


    If your boiler is still working


    1-Check the water pressure: Your boiler must have the correct pressure for the hot water to circulate your house correctly. For most systems, your pressure gauge needle should be between 1 and 2 bar. We will show you what to do if your boiler's pressure is off and how to find any pressure problems.


    To check your boiler's pressure, you need to locate the pressure gauge on your boiler. If there is the correct amount of pressure in your system, the needle should be between 1 and 2 bar. This area is usually green, and below one and greater than 2 is in red, indicating critical zones. Some boilers have a pressure gauge with 2 needles—the red needle serves as a marker while the black one shows the actual pressure. If the system has the correct pressure, the 2 should be pointing to the same number. Other boiler models have an LCD showing the water pressure.

    Artboard 1 Pressure-100

    If the boiler pressure is too low:

    If the boiler pressure falls under 1, you'll require to top up your system. The actions to do this will vary according to the specific boiler model so consult your boiler's instructions. However, in general, you'll be doing the following:


    • Turn off your boiler.
    • Use the filling loop. There are 3 types:
    • External: Connect the filling loop to the valves and slowly move the lever. Keep doing so until the pressure needle moves into the green zone. Disconnect the filling loop.
    • Keyed filling link: Embed the internal filling key into the loop and twist it until it closed. Turn the nearby knob so that water starts filling into the heating system. Do this until the pressure needle moves into the green zone. Turn the knob back to its original situation and remove the key.
    • Keyless filling link: Move the filling lever until you hear water entering the heating system. Keep the lever lifted until the pressure needle moves into the green zone. Release the lever.
    • Turn on your boiler and check to see if the pressure holds.

    If you still find the pressure falls under the recommended amount, after all, there could be a problem with the gauge or with your heating system.



    If the boiler pressure is too high:

    If the boiler pressure is above 2 bar or the needle is in the red zone, you'll need to release some of that pressure. The easiest way to do this is to bleed 1 or a few of the radiators in your home.

    • Turn off your boiler.
    • Place a radiator key or flathead screwdriver into the top valve. Turn the valve anticlockwise.
    • At first, air will escape. After that, water will begin to move out of the valve. Catch the water in a small bowl or absorbent rag.
    • Keep an eye on the pressure gauge while you do this. Keep the valve until the pressure needle falls back down into the green zone or between 1 and 2 bar.
    • Close the valve.


    2- Boiler energy efficiency: Attached to your boiler, you will see the SAP2009 annual efficiency rating, which gives you the efficiency rating of your boiler. You can find the table on the right, and your boiler should sit around on that scale. So now, when someone mentions replacing a "G" rated boiler, you know what they are talking about.


    Now you know the energy efficiency rating (both number and banded letter) and the usage. You can do simple maths to see what kind of financial savings you would make by installing a new boiler:

    Artboard 1_2 Themprature-100



    • Estimate how many functional heat units your current boiler produces per year.


    • Find out how many equivalent kWh of fuel my new boiler would have to burn to produce the same number of units of proper heat.


    • Calculate how much less gas you are using by fitting a new boiler.


    • Multiply the units of gas saved by the average cost of gas (4.5p / kWh)


    Average boiler costs £2500 for replacing a D-rated boiler with the A-rated boiler, about £1970.88 of savings over the next 12 years (without factoring in any increases in energy prices over that time). You can begin to see that, and it may be worth considering!

    However, the issue is more pronounced if you have to pay a yearly sum to keep your boiler alive. Suppose you are paying £200 a year to get a plumber out to essentially put a plaster on your boiler to get it through another winter. In that case, it becomes an even more attractive proposition.


    3- check the radiator valves: This is an effortless thing to do. Open up the valves on every radiator in the house by turning them anticlockwise. Thermostatic valves or older wheel-head valves can be turned easily by hand. Still, the lockshield valve will need a plastic adjuster or a spanner to open it. You can change the radiator valve if the boiler is working, but the radiator is still cold. Sometimes the problem is from the radiator valve.

    If you have cold spots, The most common problem is cold spots on the radiator, whether on the bottom or the top. These so-called 'cold spots' occur when an obstruction prevents the water from flowing inside the radiator. The areas it doesn't reach are left unheated.


    4-Check if the boiler is condensing: A condensing boiler uses new technology to waste less energy and give you more heat for your money. Modern condensing boilers are typically at least 93 per cent energy efficient, rising to up to 97 per cent for the very best models on the market. If you currently have a boiler installed in your home and aren't quite sure if it's a condensing boiler or not, there are a few things you can check with your system or in your boiler manual.

    • When was it installed? If your boiler was installed in your home after April 2005, the regulations put into place at this time would mean your boiler will be a condensing one. All boilers manufactured after this time are condensing.
    • Check the flue. If your boiler has a metal flue for excess gases, then your boiler will probably be non-condensing. Condensing flues are usually through an external wall or your roof.
    • Steam and drainpipe. If you can see the steam coming from the flue into an external wall (or roof), and if you also have a white plastic pipe coming to a drain, this will be of a condensing boiler.

    Artboard 1_1 Radiator-100


    What we installers can do for you


    We provide nationwide boiler installation service and offer you a free Google Nest thermostatnext-day installation, and a ten-year warranty. We deliver you all these services once we fit your boiler:


    1. Magnetic filter
    2. Condensate pipework
    3. Water treatment & chemical flush
    4. Worcester keyless filling link
    5. Electrical work
    6. Warranty registration & Building Control Certificate
    7. Scale reducer
    8. Filling loop
    9. Removal & disposal of your old boiler


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