Boiler Help & Advice
Simple troubleshooting guides to help you fix common issues safely. If these tips don't work, our Leicester engineers are just a phone call away.
How to Top Up Boiler Pressure
If your boiler pressure gauge is in the red zone (below 1.0 bar), your heating may not work. Here is how to fix it:
- Switch off your boiler.
- Locate the filling loop (usually a silver flexible hose underneath).
- Open the small valves (usually black taps) slowly. You should hear water rushing.
- Watch the gauge rise to 1.5 bar.
- Close the valves tightly. This is critical!
- Reset the boiler.
Bleeding Radiators
If your radiators are hot at the bottom but cold at the top, air is trapped inside.
- Turn off your heating and wait for radiators to cool.
- Use a radiator key on the small valve at the top side.
- Turn slowly anti-clockwise. You will hear a hissing sound (escaping air).
- Wait until water starts to trickle out, then close it immediately.
- Check your boiler pressure—it will likely have dropped and need topping up (see guide 1).
Important: If your radiator is hot at the top but cold at the bottom, bleeding will not fix it. That’s usually sludge (magnetite). See: Radiator cold at the bottom guide.
More Guides & Helpful Pages
Straightforward answers to the problems we see most often in Leicester homes.
Fault Guide
Boiler Losing Pressure
Common causes, safe checks, and when to call an engineer.
Read guide →Radiators
Radiator Cold at the Bottom (Not Air)
The sludge/magnetite truth — why bleeding won’t help and what actually fixes it.
Read guide →Fault Guide
Boiler Won’t Ignite
What it usually means and the best next steps.
Read guide →Servicing
Boiler Service Checklist
What a proper service should include (not just a quick look).
Read guide →Pricing
Boiler Service Prices Leicester
What affects cost and how to spot “too cheap to be true”.
View prices →Buying Guide
Best Combi Boilers Leicester
Reliability, value and what suits Leicester homes.
Compare boilers →Cost Guide
New Boiler Cost Leicester 2025
What impacts price and how to budget properly.
View costs →Landlord Guide
Landlord CP12 Guide
What a CP12 covers and what landlords must do.
Read guide →When to Call an Engineer
If DIY checks don’t solve it, these links take you straight to the right service page.
If your pressure keeps dropping after topping up, you likely have a leak or failing component — we can help with boiler repair in Leicester. (Guide: Boiler Losing Pressure)
If the boiler still won’t light after a single reset, it’s time to get it checked — emergency boiler repair near me. (Guide: Boiler Won’t Ignite)
Want it done properly with safety checks and documentation? Book a boiler service in Leicester. (Guide: Boiler Service Checklist)
If you’d like a clear price confirmed before we attend, start here: boiler service Leicester. (Guide: Boiler Service Prices Leicester)
Once you’ve shortlisted a boiler, the biggest difference is correct sizing and fitting — new boiler installation in Leicester. (Guide: Best Combi Boilers Leicester)
For a fixed quote based on your home (flue route, pipework, controls), see our boiler replacement in Leicester page. (Guide: New Boiler Cost Leicester 2025)
For radiator issues where bleeding doesn’t help (hot top, cold bottom), it’s usually sludge — we can advise on the right next step via our radiator cold at the bottom guide. (Often leads to a power flush assessment.)
If you need this done for a rental property, we cover the full process on our landlord safety certificates page. (Guide: Landlord CP12 Guide)
The Winter Ready Checklist
Don't wait for the first snow. Check these 5 things now.
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1. Test the heating NOW (September/October)
Switch your heating on for 15 minutes before it gets cold. If the pump is seized from summer inactivity, it's better to find out now than when it's -2°C.
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2. Check your Carbon Monoxide Alarm
Press the test button. Carbon monoxide is odourless and deadly. If the alarm doesn't beep, replace the batteries or buy a new unit immediately.
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3. Insulate the Condensate Pipe
If your boiler has a white plastic pipe running outside, wrap it in foam lagging. This prevents it from freezing shut, which is the #1 cause of boiler failure in winter.
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4. bleed your radiators
Run your hand (carefully) over your radiators. If they are cold at the top, bleed them to release the air so they heat up fully. If they are cold at the bottom, bleeding won’t help — see our cold-bottom radiator guide.
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5. Check the Pressure
Ensure the needle is between 1.0 and 1.5 bar. If it's lower, top it up. Low pressure makes the boiler work harder and less efficiently.
Quick Troubleshooting
My condensate pipe is frozen (Winter)
In very cold weather (below zero), the white plastic pipe outside can freeze. This blocks the boiler drain.
The Fix: Pour warm water (NOT boiling water, or the pipe will crack) over the pipe to melt the ice. Once cleared, reset the boiler.
I have a Worcester Bosch 'EA' Code
The EA code stands for "Flame Detection Error". It means the boiler tried to light but failed.
Check you have gas supply (check other appliances). If you have gas, the issue is likely a frozen condensate pipe (see above) or a dirty sensor. If resetting doesn't work, you need a Gas Safe engineer.
How often should I service my boiler?
Manufacturers require an annual service to keep the warranty valid. It is also vital for safety to prevent carbon monoxide leaks. We recommend servicing in late summer (August/September) so you are ready for winter.
Still No Heating?
Some jobs aren't DIY. If you smell gas, or your boiler is making loud banging noises, turn it off and call us immediately.
Get a Free Quote
For urgent boiler breakdowns, call 0116 4422959 for 24/7 emergency assistance.
Contact Details
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24/7 Emergency Line
0116 4422959 07811 216275 -
Email
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Head Office
30 Newton Lane, Wigston
Leicester, LE18 3SE
Office Hours (For Quotes & Bookings)
The phone line is monitored 24/7 for genuine emergency callouts only.