Do you want your boiler to keep working at peak efficiency? For that, you must ensure that all the boiler components are working properly. The east of these to prevent is ensuring that it has ideal pressure to keep your water and home hot.
Since boilers are susceptible to pressure, it’s indispensable for them to have it in the optimal range. The optimum range of the boiler lies between 1.0 to 1.5 bar when there is no heat and 1.0 to 2.0 bar when the boiler is heated.
However, what to do when the pressure deviates from the optimum range? There are different scenarios that can cause deviation. Our detailed guide will answer all your queries and help you understand the optimal boiler pressure.
The Ideal Boiler Pressure Range
Ideal boiler pressure is crucial to get the best results out of the whole system. According to sources, residential space and water heating take up to 23% of the total energy demand in the UK. The pressure varies depending on whether your heating is off or on. So, it is crucial to maintain ideal pressure for peak performance and reduced energy demand.
Let us discuss everything in detail.
- Pressure Range When Boiler’s Heating Is On
When the boiler is working and the heat is supplied, the optimum pressure ranges between 1.5 and 2.0 bar. Generally, all the boilers have a pressure gauge indicating the boiler’s pressure. The green-coloured area indicates the normal pressure range, while the red indicates the critical zones. All pressure gauges have a fine needle pointing to the boiler’s current pressure range.
- Pressure Range When Boiler’s Heating Is Off
With your heating system is off, the pressure range of the boiler should be between 1.0 and 1.5 bar. The pressure gauge needle will stay in the green area, ranging between points 1.0 to 1.5 bar.
The pressure can vary between this range depending on the model and manufacturer of your boiler. Most manufacturers recommend 1.3 bar as the optimum pressure for a working boiler.
What Will Happen If The Boiler Pressure Is Too Low Or Too High?
Boiler pressure is the pressure of hot water in the boiler. It is a crucial aspect for your boiler to work correctly. Having the pressure too low or high can lead to unfavourable circumstances. With high pressure, the boiler can go into a lockout state. With low pressure, the boiler will go either into a lockout state or give poor heating and water supply. Let us discuss both scenarios in detail.
Too Low Boiler Pressure
When the needle of the pressure gauge dial points towards the critical zones (red-coloured area), that is readings below 1.0 bar, then the pressure is too low. The boiler will go into the lockout state and most often you will get an error code on display.
Before increasing the pressure and restarting your boiler, you need to find the main culprit that caused the low-pressure issue. Generally, a leak within your heating system is the main culprit. The leak happens due to small pin holes at different sites like pipework joints, boiler components, or the radiator itself.
Too High Boiler Pressure
The second scenario is when the pressure gauge indicates a reading above 2.0. The needle will be in the critical zone, and you will get a reading between 3.0 to 4.0 bar. Here, either the boiler will shut down or break down. Generally, your boiler will shut down as the PRV (Pressure Release Valve) comes into play. The worst case is that your boiler will break down totally due to its prolonged high pressure.
A faulty boiler component or too much water in the system can lead to high boiler pressure. So, it is necessary that you get the boiler checked properly before restarting it.
Follow These Necessary Steps When
When the boiler pressure is not optimum, the boiler and heating system will not work properly. There are different scenarios at play that can cause the malfunction. In this section, you’ll find out what to do in different scenarios. So, let us dive into the details
Your Boiler Pressure Is Too Low
When the pressure is too low, you can repressurise or top-up your boiler and restart it for normal functioning. There are different methods to repressurise the boiler depending upon the model and manufacturer of your boiler.
Generally, there are three different mechanisms, namely, filling loop, filling key, and keyless filling link system. Let us dive into the details of these methods.
Repressurising Through A Filling Loop
- First, you must ensure that the radiator is turned off.
- Now you need to connect the filling loop to the filling taps. You need to close the filling taps by turning them to align across the pipes.
- Also, make sure that there are no filling tap caps. If there are, you can remove them by turning them in the anti-clockwise direction.
- Now connect the filling taps using the filling loop and turn the filling taps to align with the pipes.
- It will allow the water to enter the boiler.
- While the taps are open, you must keep an eye on the pressure gauge. The needle will start rising.
- Once the needle comes between 1.0 and 1.5, the reassuring green zone, you can turn off the filling taps to stop the water from entering.
- Voila, now you can turn the heating system on and ensure that the radiator is heating evenly.
Repressurising Through A Filling Key
- Turn off the radiator before starting any further steps.
- You need to locate the filling key, which will be inside the bottom panel of the boiler system.
- Unlock the bottom panel by pulling it forward and removing it from the boiler system. Look for the key and remove it from the tray.
- Now look for a black unit with a hole under the boiler system.
- Insert the key in the hole and push it upwards to align the arrow on the key with the open padlock symbol.
- Now turn the key in the clockwise direction, so the arrow on the key aligns with the closed padlock symbol on the black unit.
- Now open the white nut with your hand. You can find it next to the black unit. This will allow the water to enter the boiler unit.
- While the nut is open, keep an eye on the display unit of your boiler. Once the boiler pressure comes into the green zone, which is between 1 to 1.5 bar, then close the white nut.
- Turn the filling key so that the arrow aligns with the open padlock symbol and pull it down to remove it.
- Make sure you firmly grip the key, as pulling it off can be tricky. Also, some water will fall out, which is entirely normal. You can dry the water using an old cloth.
- All done. Now place the key in the tray and fit it back under the boiler system.
Repressurising Through A Keyless Filling Link
- You will find the keyless filling link inside the bottom panel of the boiler system.
- Remove the tray so that you can access the link.
- Now pull the blue valve to allow the water to enter the boiler system. You will hear a hissing sound.
- Keep an eye on the pressure gauge while repressurising the boiler system. Once the needle enters the green zone and the pressure is between 1.0 to 1.5 bar range, leave the valve. This will stop the flow of water.
- All done. Insert the bottom tray back, and you can turn on the heating system.
Your Boiler Pressure Is Continuously Dropping
When you find the boiler pressure dropping even after repressurising it, there may be a serious underlying problem. Here are some issues that can cause the pressure to drop continuously.
Leak In Pipework, Heating System And Boiler
A leak in the heating system or pipework can be a little tricky to spot. You will have to trace the whole pipework to check for any sign of leakage. Make sure you check all the joints and bends in pipework as, with time, they will weaken and develop some pin holes causing the leakage.
You also need to check the boiler itself. If you want to check the boiler yourself, then you need to remove the top and look for leakages. It is hard to find tiny spots, so it is better to call a professional to have a look at everything.
You can repair the leak yourself, but it is recommended to call a professional to identify everything and reseal the leaks properly. They can re-pipe, reseal all the leakages, and ensure that your system is working properly.
Faulty Component
Sometimes a faulty boiler component or malfunctioning safety valves can cause a pressure drop in the boiler system. There can be a leak in the boiler heat exchanger or any other component. In these scenarios, these components are either repaired or replaced by a qualified engineer.
Your boiler pressure is too high
When the pressure rises above 2.0, and the needle indicates a reading between 3.0 to 4.0 bar, you need to reduce the pressure and look for the underlying cause. Here are the common issues that can cause high pressure in the boiler and the steps to tackle them.
Faulty PRV
The first thing to check is whether the PRV is appropriately closed or not. If it is even slightly open, it can allow the air to enter the boiler, increasing the pressure. So, check the PRV and ensure that the valve is tightened correctly.
Higher Water Quantity In The Boiler
Sometimes, when you repressurise the boiler, you can accidentally add too much water, leading to high pressure. You need to bleed the radiator with the key. Here are the steps to follow for bleeding the radiator.
- Locate the radiator valve.
- Use the key and turn the valve in the anti-clockwise direction to open it.
- When you open the valve, the air will escape first, and the water will follow.
- While doing so, keep an eye on the pressure gauge and close the valve once the needle enters the green zone.
- All done.
FAQs
Boilers don’t last forever. On average, a boiler’s lifespan lies between 10-15 years. After it, it can often cause malfunction and require many repairs. There are several reasons why you will find that replacing the boiler is a better option than repairing it. Here are some of them.
The boiler stops working after a long lifespan of 10+ years.
There are regular leakages in the boiler
The cost of repairs and annual servicing of the boiler skyrockets and adds a burden to your budget.
The faulty components cannot be replaced due to their non-availability in the market.
When you start experiencing these scenarios, you need to switch lanes and seriously think of replacing the boiler unit rather than hanging it with life support. Replacement is a far better option than an expensive repair on the old boiler.
The expansion vessel is responsible for keeping the pressure consistent in the boiler and preventing any sudden spike. If the component is malfunctioning or broken, you should immediately call a professional engineer and avoid fixing it yourself.
Here are some steps to prevent boiler pressure from rising further than the normal range.
Make sure that the PRV is appropriately closed.
Avoid overfilling the boiler while repressurising the boiler.
Make sure that the filling taps are closed after repressuring the boiler using the filling loop.
Key Takeaway
Keeping the pressure in the optimum range of 1.0 to 1.5 while there is no heat and 1.5 to 2.0 on heating will allow the boiler and heating system to work efficiently. Any pressure outside this range will alter the functioning and give poor results.
In the above article, you will find different scenarios in which pressure deviates from the normal range and steps to tackle them. You can follow the desired course of action according to your issue and resolve it to ensure the proper working of your system.
