How Often Should I Bleed Radiators?

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Bleeding your radiators should be an exercise in maintaining your heating system to keep it as efficient as possible. By releasing any trapped air, you can make your radiators work more effectively to heat your home and see a reduction in your energy bills.

You should be alerted when it is time to bleed your radiators whenever you hear a gurgling or banging sound as this is a sign of trapped air. 

Learning how to bleed your radiators, and why you should, is knowledge that could save you money. In this guide, we will also look at when you should bleed your radiators and how often you should. 

Why You Should Bleed Your Radiators

Saving money on your energy costs could mean insulating parts of your home to prevent heat loss but a simple method is to bleed your radiators. When winter approaches, you will begin to rely on your central heating system to keep you toasty indoors.

Before you turn the radiators on, you should bleed them first to remove any trapped air and ensure a more energy efficient heating system. It does not take long to bleed your radiators and is really easy to do too.

Trapped air can be considered almost a natural occurrence for your radiators which comes from the heating then cooling of water which produces air bubbles. Unfortunately, this trapped air has nowhere to go and can displace the hot water as it tries to get around your radiator.

The trapped air effectively means air pockets which become cold patches around the top half of your radiator.

Your heating system will still be trying to heat up the radiator but you may opt for turning up the thermostat which means spending more money on your energy bills when you really do not have to.

When To Bleed Your Radiators

Whenever you can hear noises such as gurgling or banging from your radiators, that is a sure-fire sign that it is time to bleed them. Perhaps it is taking a longer time than usual for your radiators to heat up.

Also, if you have the heating on and you can discern that the top half of the radiator is clearly cooler than the bottom half, this also indicates that it is time to bleed your radiator. 

Noticing these signs and acting on them could save you money from not having to pay higher energy bills. If you are planning to have a smart radiator control fitted, make sure that you bleed your radiator beforehand. 

How To Bleed Your Radiators

Before you begin to bleed your radiator, make sure you have a radiator bleed key, or a flathead screwdriver, and a towel. You can pick up a bleed key from a DIY shop and the towel is simply to catch any leaks. 

  • Begin by turning off your heating and use the bleed key to turn the valve located at the top of the radiator. This is the bleed valve and is typically a hole with a square part in the middle.
  • You will hear the trapped air escaping when you turn the valve as it will make a hissing sound, if there are any drips then these should be collected by the towel.
  • Re-tighten the valve once the hissing has stopped as you should see liquid coming out instead.
  • Turn your heating back on then check the pressure gauge on your boiler as it should have dropped.
  • After a few minutes, return to your radiator and consider whether the heat is evenly distributed.

How Often You Should Bleed Your Radiators

You should bleed your radiators whenever you hear the gurgling or banging noises. However, as a good rule of maintenance, you should bleed your radiators every year when it begins to get cold.

By ensuring that the heating system is as efficient as it can be when you need it, you can save on your energy bills. If you are considering installing a smart system such as a Wundasmart Hub or getting a smart radiator head fitted then you should bleed your radiators first. 

How Often Should I Bleed Radiators?

While bleeding your radiators prior to the seasons changing into winter is a good idea, you may want to do it twice a year. The bleeding process on each radiator may only take a minute or so and you can mark it in your calendar so you do not forget.

Doing so at the beginning of winter is likely to be the best time as you can determine any problems with your heating system and eradicate them before you have to suffer paying higher energy costs. 

Frequently Asked Questions

Can You Bleed A Radiator While The Heating Is Still On?

You could bleed a radiator while the heating is still on but you should not.

You could risk scalding yourself with the hot air and hot water existing in the heating system.

Even if you have had the heating turned off for a few hours, the radiators may not have fully cooled as the bleeding could result in the release of some very pressurised, very hot air.

What Are The Reasons Why One Radiator May Be Cold?

A single cold radiator should typically indicate air in the system or a stuck valve in that single radiator. The flow of hot water to the radiator is controlled by the thermostatic radiator valve and this should be checked when determining why that radiator may be cold. 

Final Thoughts

For a simple measure that may only take between 20 and 30 seconds, bleeding your radiators when you sense that winter is coming should be an annual occurrence.

You may even want to do it twice a year to ensure the heating system remains efficient but keep checking the radiators for cold patches.

When you do decide to bleed your radiators, this should certainly be before you have a smart radiator control fitted. With a system like Wundasmart, you can increase your energy efficiency even further. 

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