Updated on 10th May, 2023 by Martin Astley
If you own a combi boiler, understanding the function of a diverter valve is crucial. The diverter valve on the boiler is a vital component of your central heating system. The diverter valve on a combi boiler is a lever behind the bath taps that can be pulled up or pushed down. If damaged, you may experience issues with your home’s heating and hot water supply.
In this article, we will explain what a diverter valve is, its purpose, the problems that can arise from a broken diverter valve and the associated costs. By the end of this article, you will better understand the importance of maintaining your boiler’s diverter valve.
What is a diverter valve?
The purpose of a combi boiler diverter valve is to redirect and regulate the flow of water. It manages both the water flow for domestic use and the water flow that heats the radiator. Unlike systems and regular boilers with separate hot water storage cylinders, diverter valves are only necessary for combi boilers when hot water is needed on demand.
Diverter valves are essential to combi boilers, ensuring hot water is delivered efficiently and effectively. Controlling the water flow helps maintain a consistent temperature and pressure, which is crucial for comfort and safety.
What does a diverter valve do?
A diverter valve is responsible for automatically shutting down the water flow to your radiators and redirecting it to your taps when you use it for hot water. Vice versa, when you turn off your taps, the diverter valve will open again and let the water flow back into your heating system, providing you with an uninterrupted supply of hot water.
A diverter valve is a crucial component that ensures you get hot water on demand without affecting your heating system’s efficiency. Apart from that, it minimises energy waste and saves you money on your energy bills.
Symptoms of a faulty diverter valve
1. Hot water but no heating
A frequent issue that suggests a defective diverter valve is the absence of heating from the radiator despite receiving hot water. This occurs when the diverter valve becomes stuck on the heating side, obstructing the water flow to the radiators.
To elaborate, the diverter valve directs water flow in a heating system. It can disrupt hot water distribution when it malfunctions, leading to a lack of warmth in certain areas of your home. This can be particularly frustrating when a reliable heating system is essential during the colder months.
Related article: I have no hot water but central heating works.
2. No hot water or lukewarm hot water
One of the main issues caused by a faulty diverter valve is that it can allow heat to escape from the water supplied to your hot water taps and showers if it is slightly stuck open on the heating side. This can be quite bothersome, as one of the unique selling points of a combi boiler is its ability to prioritise the supply of hot water over overheating.
A malfunctioning diverter valve can decrease the efficiency of your heating system, resulting in higher energy bills and a less comfortable living environment. It is important to address this issue promptly to avoid further complications.
3. Central heating must be on to get hot water.
A common issue arises when the central heating system must be turned on to access hot water. This is often due to a malfunctioning diverter valve, which becomes stuck and restricts water flow. Ensure you have no hot water because of the faulty diverter valve. Turn on your hot water; if there is no hot water, then turn on your central heating, and if you get hot water after turning your central heating on, the problem is because of the broken diverter valve.
Should I consider buying a new boiler?
Investing in a new boiler can save you money in the long run by reducing energy bills and avoiding frequent repairs. Additionally, modern boilers are more energy-efficient and environmentally friendly, making them a wise investment for your wallet and the planet.
Don’t let the initial cost deter you from upgrading your boiler. 24|7 Home Rescue also provides boiler on finance options that allow you to spread the cost over some time, making it more manageable for your budget.
How do you repair your broken diverter valve?
It is strongly recommended that you don’t try to fix your diverter valve on your own. This is a technical issue that only certified heating engineers should handle. If you attempt to repair it and something goes awry, your entire central heating system could be compromised. Therefore, to have your broken diverter valve fixed, it is best to contact a GasSafe engineer.
If you have a boiler cover policy, contact your insurance provider for assistance. By doing so, you can ensure that your heating system is repaired safely and efficiently. If you don’t have boiler cover, then contact 24|7 Home Rescue, and we will help you get the policy that suits your needs.
Cost of diverter valve replacement or repair
To provide you with an overview regarding the repair and replacement cost of the diverter, the amount you should expect to pay lies between £250 and £350.
However, to provide you with more details, if we breakdown the cost online, you will find the price of the diverter ranging from £80 to £200. And let’s say you are looking to replace your current diverter valve that is valued at between £80 and £120, then add up an extra £100-£130 to cover the cost of parts and labour.
Now suppose if your current diverter valve is valued at between £150 and £200, then the additional cost, including parts and labour, would range between £160 and £200. But bear in mind that the costs I provided are just estimates, and hourly labour wage rates might vary depending on the city and region you live in.
We hope this article has helped you understand the diverter valve’s role in a combi boiler and how to tell if the valve is broken. In the event of a malfunction or to free a stuck diverter valve, you must seek the services of a Gas Safe expert to carry out the necessary repairs.
Furthermore, if your boiler is over 15 years old and the diverter valve keeps breaking down, it may be time to consider replacing it altogether. At 24|7 Home Rescue, we always offer expert advice and assistance with purchasing a new boiler or replacing an old one.
Don’t hesitate to contact us at 0345 3192 247 for more information. Our Gas Safe-registered engineers are dedicated to ensuring that your home heating system is always in top condition.