Warmflow Boiler Repairs London

Warmflow Boiler Repair Help Centre

Warmflow boiler faults, safe checks, and when to call an engineer in London.

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Quick Checks ·
Common Faults ·
Oil vs Gas ·
Repair or Replace

Warmflow Boilers: What You Need to Know

Warmflow is a Northern Irish boiler manufacturer based in County Antrim. They are best known for oil boilers, though they also produce some gas models. The Agentis range is their flagship product line.

Warmflow boilers are less common in London than in rural areas (where oil heating is more prevalent), but they are found in some properties, particularly in outer London boroughs or homes that converted from oil to gas but kept the Warmflow unit.

As an active manufacturer, Warmflow parts remain available and the company provides technical support.

Quick Checks Before You Call Anyone

These basic checks apply to most boilers and may resolve simple issues:

1. Check the pressure gauge (if fitted): If below 1 bar, you may need to top up. More detail in our complete pressure guide.
2. Note any fault indication: Warmflow boilers display fault codes or warning lights. Write down or photograph whatever you see.
3. Check your fuse box: Boilers need electricity; a tripped breaker can look like a boiler failure.
4. Check thermostat and timer: Settings can change after power cuts or clock changes. Dead batteries in wireless controls can stop heat calls.
5. Oil boilers: Check fuel level: If you have an oil boiler, check your tank. Running out of oil is a common cause of lockouts.
6. Reset once only: If there is a reset button, press it once and wait 60 seconds. If the boiler locks out again, stop and call an engineer.

Oil vs Gas Warmflow Boilers

Warmflow makes both oil and gas boilers. The fuel type affects what can go wrong:

Oil boilers (more common with Warmflow):

• Require OFTEC registered engineers for oil-specific work
• Can lock out if oil runs low or air gets into the fuel line
• Nozzle, pump, and photocell are common service items
• Annual servicing is particularly important to maintain efficiency

Gas boilers:

• Require Gas Safe registered engineers
• Similar fault patterns to other gas boilers (ignition, pressure, sensors)
• Condensate pipe can freeze in winter

Important: Our service covers gas boilers only. If you have a Warmflow oil boiler, you need an OFTEC registered engineer. We can recommend specialists if needed.

Common Warmflow Boiler Problems

Ignition failure / no flame: The boiler attempts to light but cannot establish a stable flame. On gas models, common causes include worn ignition components, gas supply issues, or frozen condensate pipes. On oil models, this often indicates fuel supply problems, a blocked nozzle, or photocell issues.

Lockout after running: The boiler starts but shuts down during operation. Could indicate overheating, flame loss, or sensor faults.

Low pressure / pressure loss (sealed systems): Pressure dropping frequently usually indicates a leak somewhere in the system, or an expansion vessel / pressure relief valve issue.

No heating or hot water: Could be a diverter valve problem (on combis), pump failure, motorised valve issue, or a control/thermostat fault.

Strange noises: Banging, kettling, or gurgling can indicate sludge buildup, limescale, trapped air, or pump problems. Read our guide to boiler noises.

Oil boiler specific: Running out of fuel: If your oil tank runs dry, you may need to bleed the fuel line before the boiler will restart. This should be done by an OFTEC engineer.

Warmflow Boiler Models

Warmflow models include:

• Agentis: Main range (oil and gas versions)
• Kabin Pak: External/outhouse models
• Utility: Older range
• B Series / U Series: Various configurations

Warmflow: Parts and Support

As an active UK/Irish manufacturer, Warmflow parts are available:

• Parts availability: Good through Warmflow directly and heating merchants
• Technical support: Warmflow provides documentation and phone support
• Warranty: Active warranties on newer installations

Repair or Replace?

Warmflow boilers can generally be repaired thanks to parts availability. The decision depends on age, condition, and repair cost.

Signs it may be time to replace:

• Multiple faults in the past 12 months
• Boiler over 15-20 years old
• Major component failure on an aging unit
• Efficiency noticeably declining (higher fuel bills)
• Considering switching from oil to gas (common in London)

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.

Boiler Servicing

Annual servicing keeps your Warmflow running efficiently and helps catch developing faults early. This is particularly important for oil boilers, which benefit from regular nozzle and filter changes.

Book your boiler service (gas models).

Renting? Landlords: Check This

Tenants: Your landlord is usually responsible for boiler repairs. Contact them first and keep written records.

Landlords: Stay compliant with our Gas Safety Certificate (CP12) service (for gas boilers). See our London landlord checklist.

London Coverage

We repair gas boilers across all London boroughs including North, South, East, West, and Central London.

For coverage and service areas, see our London coverage page.

We Repair All Major Boiler Brands

What We Need From You (To Diagnose Faster)

• Boiler model: For example Agentis, Kabin Pak, Utility
• Fuel type: Gas or oil (we service gas only)
• What is happening: No heating, no hot water, leaking, noises, fault codes
• Any fault indication: Error codes, warning lights, or display messages
• Postcode: So we can route the closest engineer

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