How to Bleed a Radiator: Step-by-Step Guide | AJL Plumbing & Heating Essex

🔧 Why Bleeding Your Radiators Matters

If your radiators aren’t heating up properly, warm at the bottom but cold at the top - you likely have trapped air inside the system. This air prevents hot water from circulating evenly, making your central heating less efficient and driving up your energy bills.

The good news? Bleeding your radiators is a simple maintenance task that can quickly restore warmth to your home.

Here’s a step-by-step guide from AJL Plumbing & Heating, trusted heating engineers across Essex, to help you get it done safely and effectively.

🧰 What You’ll Need:

• A radiator key (available at most DIY stores)

• A cloth or towel to catch drips

• A container for any water that escapes

• Optional: a pair of gloves to protect your hands

🔹 Step-by-Step Guide to Bleeding a Radiator

1️⃣ Turn Off Your Heating

Before you start, turn off your central heating system. You’ll want the radiators to cool slightly so the water doesn’t spray out under pressure.

2️⃣ Locate the Bleed Valve

Find the bleed valve, a small square or slotted screw - usually at the top corner of your radiator. Insert your radiator key into the valve.

3️⃣ Turn the Valve Slowly

Turn the key anti-clockwise slowly, just enough to let trapped air escape. You’ll hear a hissing sound - that’s the air leaving the system.

4️⃣ Wait for Water

Once water starts to flow steadily (not sputtering), quickly close the valve by turning it clockwise. Use your towel to catch any drips.

5️⃣ Check Your Boiler Pressure

After bleeding, check your boiler pressure gauge. If the pressure has dropped below 1 bar, you may need to top it up. (Refer to your boiler’s manual for instructions or call AJL Plumbing & Heating for assistance.)

💡 Tip from Our Essex Engineers

Bleed your radiators once or twice a year, ideally before winter. If your radiators keep trapping air or you notice uneven heating throughout your home, it may be a sign of sludge build-up - in which case, a power flush could be the solution.

Read our blog about power flushing here

🏠 Expert Heating Support Across Essex

If bleeding your radiator doesn’t solve the issue or your system still feels uneven, our Gas Safe registered engineers can help.

We provide reliable heating and boiler services across Essex, including:

Chelmsford • Colchester • Southend-on-Sea • Basildon • Brentwood • Braintree • Harlow • Clacton-on-Sea • Epping • Maldon • Witham • Rayleigh • Wickford • Billericay • Grays • Loughton • Chigwell • Ongar • Dunmow • Halstead

Wherever you are in Essex, AJL Plumbing & Heating can inspect your heating system, identify the cause, and restore full warmth and efficiency to your home.

📞 Need Help with Your Radiators or Boiler?

If you’re struggling with cold spots, leaks, or low pressure after bleeding your radiator, get in touch with AJL Plumbing & Heating Ltd today.

Our friendly team of Gas Safe engineers are on hand to help with:

• Radiator and heating repairs

• Boiler servicing and installations

• Power flushing and system cleaning

• Central heating upgrades

  
  

👉 Call us on 07562899539. AJL Plumbing & Heating - your trusted heating specialists in Essex, Kent & London.