Radiators Not Heating Evenly? Here’s How to Fix It

If you’ve noticed some of your radiators are hot at the top but cold at the bottom  or worse, one room stays freezing while others are warm  you’re not alone.
Uneven heating is a common issue in many Northampton homes, especially as the weather turns colder. The good news? It’s often easy to fix!

Here’s a step-by-step guide from DM Emergency Plumbing to help you get your heating system working efficiently again.

1. Check for Air in Your Radiators

The most common cause of uneven heating is trapped air inside the radiator.
Air pockets stop hot water from circulating properly, leaving cold spots usually at the top.

How to fix it:

• Turn off your heating system.

• Place a towel under the radiator valve to catch any drips.

• Use a radiator bleed key to slowly open the valve until you hear hissing.

• When water starts to flow steadily, close the valve tightly.

• Turn your heating back on and check if it’s warming up evenly.

If you’re not comfortable doing this yourself, don’t worry we can handle it safely and quickly.

2. Balance Your Heating System

If some radiators heat up faster than others, your system may need balancing.
This involves adjusting the valves so hot water is distributed evenly throughout your home.

Signs your system needs balancing:

• Radiators furthest from your boiler are slow to heat.

• Upstairs radiators are hot, but downstairs ones are cold.

Balancing can be a bit tricky, so it’s best left to a professional plumber who has the right tools and experience.

3. Check Your Thermostatic Radiator Valves (TRVs)

Sometimes, the issue isn’t air or balance it’s a faulty or stuck TRV.
These valves control the temperature of each radiator individually.

Quick check:

• Make sure the TRV is turned up to the desired setting.

• If it’s not working or feels stuck, it may need replacing.

DM Emergency Plumbing can replace TRVs quickly to restore full heating control.

4. Look for Sludge Build-Up

Over time, rust, dirt, and debris can build up inside your heating system, creating sludge that blocks water flow.

Symptoms of sludge build-up:

• Radiators are cold at the bottom but warm at the top.

• Strange noises from your boiler or pipes.

• System takes longer than usual to heat up.

The fix is a power flush  a professional cleaning process that removes all that sludge and improves system performance.

5. Check Your Boiler Pressure

Low boiler pressure can reduce heating performance and affect how water flows through your system.

To check:

• Look at the pressure gauge on your boiler  it should read between 1.0 and 1.5 bar.

• If it’s below 1, you may need to top it up.

If pressure keeps dropping, it might indicate a leak or system issue  best to call a plumber to investigate.

🚨 Still Having Heating Issues?

Don’t let uneven heating leave your home cold and uncomfortable.
Our team at DM Emergency Plumbing is available 24/7 to diagnose and repair heating problems quickly and safely.

📞 Call us now
🕒 Fast response for boiler repairs, radiator issues, heating breakdowns & leaks
📍 Serving Northampton and surrounding area