Common Boiler Problems, Issues & How to Resolve Them

A Practical Guide for Homeowners & Landlords in Lancashire & Greater Manchester

GAS TECH PLUMBERS LTD – Gas Safe Registered Engineers

For homeowners and landlords across Lancashire and Greater Manchester, a reliable boiler isn’t a luxury — it’s essential. With long, cold winters in areas such as Burnley, Blackburn, Preston, Bolton, Manchester, Oldham, Rochdale, Bury, Accrington, and Clitheroe, boiler breakdowns can quickly turn from inconvenient to serious emergencies.

This in-depth guide explains the most common boiler problems, what causes them, what you can safely check yourself, and when it’s time to call a qualified heating engineer.

Important Legal Notice for Landlords

⚠️ UK law requires landlords to ensure all gas appliances are checked annually by a Gas Safe registered engineer and that a valid Gas Safety Certificate (CP12) is in place. Failure to comply can result in fines, invalid insurance, or prosecution.

1. No Heating or No Hot Water

Common Symptoms

• Radiators are cold

• No hot water at taps

• Heating works but hot water doesn’t (or vice versa)

• Boiler runs but doesn’t heat properly

Likely Causes

• Faulty thermostat or timer

• Low boiler pressure

• Air trapped in radiators

• Failed diverter valve (common in combi boilers)

• Motorised valve failure (system boilers)

What You Can Safely Check

• Set the thermostat above room temperature

• Check boiler timer/programmer settings

• Ensure boiler pressure is 1.0–1.5 bar (when cold)

• Make sure radiator valves are fully open

When to Call an Engineer

• Topping up pressure doesn’t fix the issue

• The fault keeps returning

• Tenants are without heating or hot water (legal risk)

2. Low Boiler Pressure (Very Common in Lancashire Homes)

Low boiler pressure is one of the most frequent callouts, especially in older housing stock across Burnley, Accrington, Blackburn, and Rochdale.

Symptoms

• Boiler switches off

• Error codes appear

• Heating cuts in and out

Common Causes

• Small leaks from radiators or valves

• Radiators recently bled

• Faulty expansion vessel

• Pressure relief valve discharging outside

Safe Checks

• Inspect radiators and pipe joints for leaks

• Carefully top up pressure using the filling loop

• Monitor pressure over the next few days

Engineer Required If

• Pressure keeps dropping

• Water discharges from the external relief pipe

• You can’t locate the leak

3. Boiler Keeps Switching Off or Locking Out

Symptoms

• Boiler fires briefly then cuts out

• Frequent resets required

• Flashing lights or fault codes

Likely Causes

• Low system pressure

• Blocked system or magnetic filter

• Air in the system

• Pump or sensor faults

• Frozen condensate pipe (winter issue)

4. Frozen Condensate Pipes (Very Common in Lancashire Winters)

In colder areas such as Clitheroe, Oldham, Bolton, and rural Lancashire, frozen condensate pipes are a major cause of winter breakdowns.

Symptoms

• Boiler suddenly stops

• No heating or hot water

• Gurgling noises

• Flue or ignition fault codes

Safe DIY Fix

• Locate the external plastic condensate pipe

• Pour warm (not boiling) water along the pipe

• Reset the boiler after thawing

Prevention

• Insulate the external pipe

• Ask an engineer to re-route or shorten it internally

5. Cold Radiators & Uneven Heating

Symptoms

• Radiators cold at the top

• Some rooms heat, others stay cold

• Poor comfort throughout the property

Common Causes

• Trapped air

• Sludge build-up

• Poor system balancing

What You Can Do

• Bleed radiators regularly

• Top up pressure afterwards

• Ensure radiator valves are open

Engineer Required If

• Radiators are cold at the bottom (sludge)

• System hasn’t been cleaned for years

• Rental property has recurring heating issues

6. Loud Noises: Banging, Whistling & Kettling

Common Sounds

• Banging when boiler starts

• Whistling like a kettle

• Gurgling in pipes

Likely Causes

• Limescale on heat exchanger

• Sludge in the system

• Trapped air

• Faulty pump

These issues are common in hard water areas across Lancashire and Greater Manchester.

Professional Solutions

• Chemical or power flushing

• Magnetic filter installation

• Pump and heat exchanger inspection

7. Boiler Leaks

Symptoms

• Water pooling beneath the boiler

• Damp patches on walls

• Constant pressure loss

Common Causes

• Corroded joints or seals

• Faulty pressure relief valve

• Internal heat exchanger damage

⚠️ Never remove the boiler casing yourself. Internal leaks must be inspected by a Gas Safe engineer.

8. Pilot Light & Ignition Failures

More common on older boilers still found in Preston, Bury, and Accrington.

Possible Causes

• No gas supply

• Faulty ignition electrode

• Blocked burner

• Flame sensor failure

🚨 If you smell gas: Turn off the supply, ventilate the property, and call the National Gas Emergency Line (0800 111 999) immediately.

9. Boiler Error Codes

Modern boilers display digital fault codes.

Best Practice

• Write down the exact code

• Check the boiler manual

• Attempt one reset only

Repeated fault codes usually indicate an internal fault requiring professional repair.

Preventing Boiler Problems

Essential Advice for Lancashire Homeowners & Landlords

• Annual boiler servicing (mandatory for landlords)

• Magnetic filters to trap sludge

• Inhibitor chemicals to prevent corrosion

• Regular pressure checks

• Radiator bleeding

• Condensate pipe insulation before winter

Preventative maintenance often saves hundreds of pounds in emergency repair costs.

Special Advice for Landlords

If you rent property in Burnley, Blackburn, Preston, Bolton, Manchester, Oldham, Rochdale, Bury, Accrington, or Clitheroe, you are legally responsible for:

• Annual Gas Safety Checks

• A valid Gas Safety Certificate (CP12)

• Prompt heating and hot water repairs

• Safe and efficient appliances

Failure to comply can result in:

• Heavy fines

• Invalid insurance

• Criminal prosecution

• Tenant legal claims

Final Thoughts

Boiler problems are unavoidable over time, but most breakdowns give warning signs before total failure. Knowing what to check — and when to call a professional — helps you:

• Keep your home warm

• Extend boiler lifespan

• Protect tenant safety

• Avoid emergency callouts

• Stay legally compliant

Need a Reliable Local Boiler Engineer in Lancashire?

If you’re based in Burnley, Blackburn, Preston, Bolton, Manchester, Oldham, Rochdale, Bury, Accrington, or Clitheroe, expert help is always close by.

We provide:

• Boiler repairs

• Annual boiler servicing

• Landlord Gas Safety Certificates (CP12)

• Power flushing

• Boiler upgrades

Having a trusted local Gas Safe registered engineer makes all the difference.