Vokera Boiler Repairs London

Vokera Boiler Repair Help Centre

Common Vokera faults, fault codes, safe checks, and when to call a Gas Safe engineer.

We specialise in Vokera boiler repairs across London.

Gas Safe registered engineers for safe diagnosis, repair and testing.

24/7 availability with London wide call handling and booking.

Jump to: Fault Codes · A04 Fault · Pressure · Frozen Condensate · Repair or Replace

Quick Checks Before You Call Anyone

These take 60 seconds and solve a surprising number of lockouts:

1. Check the pressure gauge: If below 1 bar, top up (see guide below). More detail in our complete pressure guide.
2. Note the fault code: Vokera displays show A codes like A01, A04, A06. Write it down before calling.
3. Check your fuse box: Boilers need electricity, a tripped switch is an easy fix.
4. Check thermostat and timer: Settings can change after clock changes or dead batteries.
5. Freezing weather? The condensate pipe may be frozen (see winter section below).
6. Reset once only: Press the reset button on the front panel once, wait 60 seconds. If it locks out again, stop and call an engineer.

Vokera Fault Codes

Note: Vokera uses A codes on most models. If unsure, call us and we will help you identify your specific code.

A04: Ignition Lockout

What is happening: The boiler has attempted to ignite multiple times and failed, triggering a lockout. This is one of the most common Vokera fault codes.

Common causes: Frozen condensate pipe (winter), gas supply interruption, faulty ignition electrode or lead, blocked or damaged flue, gas valve fault.

What to try: Check if your gas hob or other gas appliances work. In freezing weather, check the condensate pipe for ice. If gas supply is fine but the boiler will not ignite, call an engineer.

Note: A04 often appears alongside or after A01 on Vokera boilers. Both indicate ignition problems.

A12: No Circulation Detected

What is happening: The boiler is not detecting adequate water flow through the heat exchanger.

Common causes: Pump failure, airlocks in the system, blocked or restricted pipework, sludge build up, faulty flow sensor.

What to try: Check if radiators are heating. If some are cold at the bottom, there may be sludge. If the pump is not running, call an engineer. A power flush may be needed if sludge is suspected.

A06: Low Water Pressure

What is happening: System pressure has dropped below the minimum operating level.

Common causes: Small leak in the system, recently bled radiators, pressure relief valve discharge, expansion vessel needs recharging.

What to try: Top up pressure using the filling loop (see below). If pressure drops again within days, there may be a leak. Read our pressure guide for step by step instructions.

How to Top Up Pressure (Vokera)

If you are not comfortable using the filling loop, stop and call a Gas Safe engineer.

Do not remove the boiler casing. If you cannot locate the filling loop easily, call an engineer.

1. Locate the filling loop (usually underneath the boiler, a braided silver hose with one or two valves).
2. Ensure the boiler is off and cool.
3. Open the valves slowly, a quarter turn at a time.
4. Watch the pressure gauge rise to between 1.0 and 1.5 bar.
5. Close both valves fully.
6. Switch the boiler back on.

Do not exceed 2.0 bar. If you overfill, stop and call an engineer.

If you need to top up frequently (more than once a month), there is likely a leak. Call us for a diagnosis.

Frozen Condensate Pipe (Winter)

In freezing weather, a frozen condensate pipe is one of the most common causes behind A01 and A04 lockouts on Vokera boilers. This is often safe to resolve with the steps below. If you are unsure, or the boiler will not restart, call an engineer.

Signs: Boiler locked out with A01 or A04, freezing temperatures outside, gurgling sound when boiler tries to start.

What to do:

1. Locate the condensate pipe (white or grey plastic pipe exiting to an outside drain).
2. Pour warm water (not boiling) over the frozen section.
3. Reset the boiler once thawed.

Full instructions: Frozen condensate pipe guide.

If it keeps happening, we can reroute the pipe internally or add insulation to reduce future freezing.

Why These Faults Are Common in London Homes

Hard water, older pipework, and winter weather make certain faults more likely in London properties:

• A04 ignition failures: Frozen condensate pipes during cold snaps are a frequent cause. Older Vokera models can also have ignition components that wear over time.
• A12 circulation faults: London’s hard water can contribute to sludge and limescale build up, restricting flow and triggering circulation errors.
• Pressure fluctuations: Older London properties with microbore pipework or poorly balanced systems can see more A06 low pressure faults.
• Fan and flue issues: Some properties have challenging flue routes that can contribute to A03 or A10 faults in windy conditions.

Vokera Models We Repair

We repair all Vokera gas boiler models including:

• Easi-Flo: Popular compact combi range
• Mynute: Current combi and system range
• Vision: Higher specification range
• Compact: Space saving combi models
• Linea: Established combi range (widely installed)
• Excell: Older combi range
• Synergy: System boilers

We carry common Vokera parts and can source others. Parts availability is generally good.

Common Vokera Problems

Ignition failures (A01/A04): The most common Vokera repair. Often caused by worn electrodes, faulty ignition components, gas valve issues, or a frozen condensate pipe in winter.

Fan faults (A03): Fan not running at correct speed or failing to prove to the PCB.

Diverter valve sticking: Hot water works but radiators stay cold, or vice versa. Common on models over 8 years old.

PCB failure: Random lockouts, display glitches, or complete failure.

Pump failure: No circulation (A12), overheating, radiators not heating evenly.

Heat exchanger blockage: Kettling noises, overheating, reduced efficiency. See our guide to boiler noises.

Repair or Replace?

Vokera boilers typically last 10 to 15 years with proper maintenance. If yours is approaching that age and needs a major repair (heat exchanger, PCB, pump), replacement may be more cost effective.

We give honest advice either way. Read more: Repair or replace? An engineer’s guide.

If you decide on a new boiler: New boiler installation.

Vokera Servicing

Annual servicing keeps your Vokera running efficiently and helps maintain warranty terms. We service Vokera models and provide a clear report after each visit.

We recommend servicing in late summer or early autumn, before the heating season. Book your boiler service.

Renting? Landlords: Check This

Tenants: Your landlord is usually responsible for boiler repairs. Contact them first and keep written records, especially if you have no heating or hot water.

Landlords: Stay compliant with our Gas Safety Certificate (CP12) service. See our full London landlord checklist covering gas safety, EPCs, and boiler maintenance.

London Wide Coverage

We repair Vokera boilers across all London boroughs. See our London coverage area or find your local page:

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