If your boiler continues to lose pressure, it could be due to several issues that are causing it that are simple to fix while others may require the assistance of a heating specialist.
What is Boiler Pressure?
Simply put, the pressure of a boiler is the ratio of the air and water in the boiler’s system, i.e., the pipes and the components. It can also be described as the pressure exerted by hot water that is running through central heating systems that are sealed.
Additionally, in order for a boiler system to effectively move water around and also heat your radiator, the pressure has to be stable and balanced, not too high but not too. In addition, it’s common for pressure in the boiler system to rise or decrease in intervals, but drastic shifts are a problem.
In reality, a valve in the heating system known as the expansion valve is used to regulate the pressure within the boiler, by maintaining a balance of air and water. The resultant lower air-to-water ratio leads to a rise in pressure. This is also true for the high pressure ratio of air and water.
In addition, boilers that are over-pressurised could result in water leakage through the valve for pressure relief that could lead to lower pressure, or even permanent harm to the central heating equipment.
In addition, if the pressure of your boiler is not sufficient the reason is typically an outcome of leakage in water or bleeding from the radiator. Most of the time, this is not a major risk to the boiler in general, however it can impact the effectiveness of the system in heating your house efficiently and pumping water. In addition it can also impact energy efficiency and will cost you more in electricity costs.
Signs Your Boiler Pressure is Dropping
As I mentioned earlier, having a boiler with low pressure or no pressure in the boilers is harmful to your heating system as well as your budget. How can you tell the pressure of your boiler is at a low level?
Check The Pressure Gauge
The majority of boilers have the pressure gauge at the top of the controls panel. The pressure gauge is represented by an oval disk that can have an array of measurements ranging between 1-4 bar (1-5 in a handful of boilers). The marks are split between zones of red and green. The green zone represents the operating standard used for boiler pressure while the red zone represents the safest working pressure for your heating unit.
In addition, the green zone usually lies between 1.0 and 1.5(sometimes 2.0) bars on the pressure gauge, while the red zone ranges between 2.5 up to 4.0 bar. In addition, if the gauge falls below that green area, it’s a sign the boiler’s pressure is not sufficient.
Another indication that a boiler is at pressure is too low is the level of efficiency displayed by radiators that are in your home, if there are any. If your radiators aren’t warming up as they should, it is likely that the pressure in your boiler is decreasing. This can be verified by checking the gauge for pressure.
Why Does My Boiler Keep Losing Pressure?
There are a variety of factors that could be the reason why your boiler is losing pressure. This could not just be the result of the unstable nature of pressure within your boiler. It doesn’t matter if it’s a regular boiler or a combi boiler that is losing pressure, it could be due to leaky pipes, malfunctions of the expansion valve or even air trapped in your heating unit.
Here are some of the most prominent reasons for a boiler to lose pressure or experience low pressure in the water:
Leakage In The Pipework
In the beginning, there could be a leak within the pipework of your heating system in and of itself. In this scenario, the presence of water spots on your ceiling may be an indicator of damp floors. If you observe that water drips out of the pipe that is in the system or there are cracks in the pipe, this could suggest leaks in your central heating unit. To make matters worse, corroded or rusted pipes or radiators could result in leaks and an increase in pressure.
Damaged Expansion Valve
A defective expansion vessel or valve can also cause loss of pressure in a boiler when it is cold. When cold water warms up inside a boiler, or any heating device at all, the molecules are moved in such a rapid manner and expand. In a pressurized heating system, the vessel for expansion, that holds approximately half a bar of pressurized air inside a diaphragm of rubber, permits the water to warm up and expand without allowing air to enter the heating system and creating damage.
In simple terms the expansion valve is intended to accommodate the expansion caused by heated water:
Thus, if the expansion valve is defective it is likely that the increase will have no control, leading to the hot water to leak out of the relief valve. If you notice that water isn’t flowing from the relief valve it’s a good idea to inspect the Schrader valve which is situated within the expansion vessel.
It is also important to note that the Schrader valve looks identical to the air valve found on the tire of a car or bicycle in function as well as appearance. By removing the plastic cover of the Schrader valve and then removing the cover, you’ll be able to press the pin in the valve. If you notice that water is flowing out, instead of air, that means the expansion valve is not functioning properly. In addition, the diaphragm inside the vessel could be damaged and the vessel will have to be replaced.
The Air In The Heating System
Another reason that can reduce the pressure in your boiler can be due to the air present within your heating unit. The process of checking for air in your boiler is a simple task and can be performed on your own without the need to contact an engineer or technician.
If your boiler system is equipped with radiators, the first step to do is bleed them. This can be accomplished by finding the valve that bleeds radiators and turning it counter-clockwise until water begins to pour out. This allows trapped air to escape and allows hot water to enter those cold fins. Sometimes bleeding radiators may not work. In this instance, it’s recommended to contact an expert.
Leakage In The Relief Valve
The last but not least is that the valve for pressure relief in your boiler may also be a trouble spot, causing the heating system to lose pressure. system. The water leakage may result from dirt or other debris that is stuck inside the valve. In this scenario the valve would have to be cleaned or replaced by a heating engineer.
What Pressure Should My Boiler Be?
To ensure that water flows efficiently throughout your home Your boiler needs to have the proper quantity of pressure. A majority of boiler heating systems nowadays are closed systems which means that they do not have vents that open that let the expanding water molecules as they warm up and cool down.
They are instead closed and pressurized to handle the temperature fluctuations. Thus, pressure is vital for heating systems to work.
It is generally accepted that a reading of between 1 to two bars in the gauge is a safe limit for the majority of systems. Every boiler is unique which is why it is advised to read and adhere to the instruction manual of your boiler, or talk to the person who installed the system. To determine if your boiler’s pressure is within an optimal range, you should also examine the gauge for pressure.
If the direction the needle is in falls within the range that is standard by the guideline, it’s safe. If not, then it will be required to determine the cause of the imbalance.
Some boilers, however, are equipped with LCD pressure gauges or dials that have 2 needles rather than one (one black, the other red). The black needle signifies the pressure that is actually present, while the red needle functions as an indicator.
The LCD screens typically display water pressure, while the double-needle dials are pointing two needles at the same time if the pressure is not in the limits of critical zones.
Furthermore, the majority of pressure gauges range between 1 and 4 bars and some go up to 5 bars. The pressure is deemed to be high when the gauge is pointed to the number within those critical areas. Critical zones on most boilers are lower than 1 bar, and above 2 bars. It is typically somewhere between three and four bars on the majority of boilers.
How to Repressurise a Boiler
If you find that hot water isn’t flowing through your faucets in the way it does or the radiators aren’t heating like they should, there is a chance that your boiler requires greater pressure. In this case, then you might need to pressurize the boiler. A lot of boiler owners choose to pressurize their boilers by themselves.
If you feel at ease doing this by yourself you should go through the boiler’s manual to ensure that the procedure is simple enough to carry out by yourself. If not, it’s advisable to speak with an engineer for heating. Re-pressurizing your boiler permits more water to flow into the heating system through your main source.
To pressurize your boiler, you’ll need to:
- Shut off your boiler and let it completely cool down.
- Verify that all ends of the loop are properly connected. Underneath the boiler is a flexible, braided filling loop that is located in between the feed for cold and return. If you spot it, ensure that each side is securely attached. This is vital since the drop in pressure could be caused by leaks in the valve.
- The valves should be opened to allow cold water to be pumped into the system, and monitor any changes to the gauge of pressure. When the gauge’s pressure is 1.5 bar, shut off both valves.
- Take off the filling loop (if it’s not included) and then turn off the boiler.
- Examine the pressure gauge to confirm that the issue is fixed. Based on the boiler’s model the filling loop could be external or built-in. External loops will need to be removed and attached manually before and after the re-pressurising process. If you do happen to pressurize the system You can simply drain the radiators to let the air that is trapped out and then bring the pressure to normal. Make sure you keep in mind the gauge of pressure for the next couple of days to determine if levels of pressure remain constant.
What Can Happen if I Don’t Fix My Boiler Losing Pressure?
Modern boilers require pressure to efficiently supply warm water to domestic users as well as warm up the home. The majority of the time, low pressure isn’t a major issue for the lifespan of your boiler however, it can be extremely annoying.
This is why not addressing your boiler’s low-pressure problem could result in several unpleasant situations – one being the banging sounds that heating systems are known to produce when they are in this situation.
In addition the sudden decrease in water flow and pressure is often accompanied by a banging and a clicking sound within the pipework. A loss of radiator function will likely follow as radiators require stable pressure in order to generate heat. The most bothersome consequence of this problem is the need to endure the frigid temperatures in the home, particularly in the winter months. The most annoying thing is the need to use cold water for dishes or shower.
If the issue with low pressure isn’t addressed in time the radiators are likely to trip off or shut themselves off. A boiler with low pressure isn’t known to cause risks or dangers, but it is recommended to have it repaired to extend the life of your boiler.
When to Get a New Boiler
It is crucial to be aware of the time to replace a boiler, particularly if the boiler pressure is constantly dropping or you are constantly having to pressurize it.
Another sign is your electric bills. If you have noticed a dramatic increase in your electric bills with no explanation at all it could be because your boiler is at fault for this. The term “efficiency ratings” might not be a common term with the majority of people, but it’s an important factor to consider when buying a boiler. In simplest terms the boiler that is less efficient consumes more electricity which increases the cost of electricity.
A boiler that is more efficient does exactly the opposite. Modern boilers typically have an efficiency of 90 which is excellent however some older models operate at 70 percent. If your boiler is operating at low efficiency then it might be time to look into purchasing an upgrade.
Change In The Sound
The fact that your radiators are noisy could be a reason to replace your boiler. It is typical that a boiler will have the sound of a low hum as well as other noises. However, if you find that the sound of your boiler is now loud vibrations, tapping, or even a banging sound, despite servicing as well as repairs, then it might be wise to think about purchasing a new boiler.
Most of the time, the sounds of tapping indicate that the pipes are suffering from some debris or sludge build-up and might need to be replaced. If you hear a lot of banging or squealing noises, it could mean there’s a bigger problem with the heating or boiler system.
Changes In The Smell
Another indication that you should change your boiler is that when you start to smell an eggy or sulfuric smell coming from your heating unit, it could be a sign of an issue with gas. It is imperative to immediately switch off the boiler and then call your emergency gas number. Also, you should contact an authorized Gas Safety engineer. In many situations, the boiler might require replacement.
If you find yourself constantly fixing or paying for the repair of your boiler, it’s a good idea to look into purchasing a new replacement. When you consider the total cost of repair per year, compared to the price of purchasing a brand new boiler, buying an entirely new heating system would be a better option. Additionally, a functional boiler needs to be maintained at least twice per year.
The life expectancy for an average boiler is approximately 10 years. If your furnace is 10 years old, most likely, it isn’t the same efficient as it was. Additionally, many insurance providers have a 10 year limit on boilers. If anything goes wrong, they are not obligated to pay for the damages. Additionally, a boiler lasting approximately 10 to 15 years usually decreases its efficiency, and it could be consuming more current than it did in the past, and some even cease to function altogether.
If a part or component of your boiler has been damaged for a long time it is possible to think about buying a new boiler in its entirety. Although there are spare parts of boilers available on online stores, it can be difficult to locate the model or type you’re looking for especially if your boiler is older in design.
Heating Engineer Cost
In the event of an issue with your boiler, it is possible to contact an engineer for heating, particularly in the case of a complex issue. However, the price the heating engineer will charge is contingent on the work that is involved as well as speed at which it will take to finish repairs, and the components that need to be repaired are also factors. The engineer’s task is to identify the issue first before attempting to fix it.
In addition, the costs of hiring heating engineers differ from country to country and also from company to company. Furthermore, when you hire independently-owned heating experts, prices are also different. It is crucial to hire only registered and certified heating engineers. They must be able to provide proof of their accreditation if requested. This will ensure accountability for any issue that is discovered following repairs.
Furthermore there is the fact that in the UK the typical cost to hire an engineer for heating is £75 to £105 each hour. In order to re-pressurize a boiler the labor cost will be between £50 to £100 with tipping fees and VAT. The price could be altered depending on the amount of additional materials required. The emergency call-out charge is usually double the usual hourly rate. On average, a heating technician might charge between £120 and £150 per hour for a call-out emergency job.