London's Trusted Heating & Gas Specialists
From emergency boiler repairs to gas safety certificates and full installations — Hey Boiler's Gas Safe registered engineers are ready to help. Fast, affordable, and available 6 days a week.
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FAQs
Frequently asked questions about our boiler repair, installation, and gas safety services in London.
General
What does HeyBoiler do?
HeyBoiler provides gas safety certificates, boiler servicing, electrical safety certificates and PAT testing, emergency boiler breakdown support, and new boiler installation across selected London boroughs.
Which areas of London do you cover?
We cover Barnet, Brent, Camden, Croydon, Ealing, Hammersmith and Fulham, Hillingdon, Hounslow, Kensington and Chelsea, Kingston upon Thames, Lambeth, Merton, Richmond upon Thames, Southwark, Sutton, and Wandsworth.
Do you work with homeowners and landlords?
Yes. Our services are designed for both homeowners and landlords, including compliance-focused visits such as gas safety and electrical safety certificates.
Do you serve flats, houses, and rental properties?
Yes. We support owner-occupied homes, buy-to-let properties, flats, houses, HMOs, and other residential properties within our coverage area.
Can I book online?
Yes. You can book online and choose the service that best matches your issue. If you are unsure, contact us and we can guide you to the right booking.
Do you offer same-day appointments?
Same-day appointments are available when capacity allows. Emergency work is prioritised, especially for loss of heating or hot water.
What are your working hours?
Emergency breakdown visits are available Monday to Saturday, 8am to 6pm. Other services can be booked based on availability.
Do all your services include upfront pricing?
Yes. HeyBoiler services are built around clear, upfront pricing, and any optional or additional work is quoted before it goes ahead.
Are your engineers Gas Safe registered?
Gas work is carried out by Gas Safe registered engineers. Electrical safety work is carried out by a certified electrician.
How quickly should I book if my boiler is acting up?
Book as soon as you notice a fault. Problems such as leaks, pressure loss, ignition issues, strange smells, or repeated shutdowns can worsen and may turn into a full breakdown.
Service Delivery, Booking, Timing & Cost
How much does a gas safety certificate and boiler service cost?
Prices start from £75 for the combined gas safety certificate and boiler servicing package.
How much does an electrical safety certificate and PAT testing cost?
Prices start from £85 for electrical safety certification and PAT testing.
How much does an emergency boiler breakdown visit cost?
Emergency boiler breakdown visits start from £100, with any extra repair work quoted separately after diagnosis.
How much does boiler installation cost?
New boiler installation starts from £1,800. Final pricing depends on property layout, boiler type, flue route, controls, and any required system upgrades.
Do you provide free quotes?
Yes. Boiler installations include free quotes, and we can advise on the best setup for your home before you commit.
How long does a boiler service take?
A standard boiler service often takes around 45 to 90 minutes depending on the boiler type, accessibility, and whether additional checks are needed.
How long does a gas safety certificate visit take?
A CP12 gas safety certificate visit usually takes about 30 to 60 minutes for a straightforward property, but longer if there are multiple appliances or access issues.
How long does PAT testing take?
PAT testing time depends on how many appliances need testing. A small residential job may be quick, while larger landlord or HMO properties take longer.
How long does emergency boiler diagnosis take?
Diagnosis time varies by fault. Straightforward problems may be identified quickly, while intermittent or multi-part faults can take longer.
How long does a new boiler installation take?
Many standard swaps can be completed in a day, but some installations take longer if pipework, flues, controls, or system changes are required.
Can you tell me the total cost before work starts?
We aim to provide clear pricing from the start. If extra work or parts are needed after diagnosis, we explain the options and quote before proceeding.
Do I need to be home for the appointment?
Yes, or you should arrange access through a responsible adult, tenant, managing agent, or key holder so the engineer can inspect the system safely.
What details should I send when booking?
It helps to share your postcode, boiler make and model if known, whether you have no heating, no hot water, or both, any fault code showing on the display, and whether the issue is urgent.
Can I book if I do not know what is wrong?
Yes. Many customers only know the symptoms, such as a leak, a cold house, or no hot water. We can help identify the right service or emergency visit.
Do you charge separately for repairs after a service or safety check?
Optional repairs are quoted separately. The inspection, service, or certificate does not automatically include parts or remedial work unless stated in the quote.
Do you prioritise repeat customers for emergency work?
Yes. Returning customers can receive priority booking for emergency breakdown support.
Gas Safety Certificate & Boiler Servicing
What is included in your gas safety certificate and boiler servicing package?
The package includes a CP12 gas safety inspection, a full boiler service, and a digital or printed certificate. Optional repairs are quoted separately if needed.
What is a CP12 gas safety certificate?
A CP12 is the record issued after a gas safety check on gas appliances and related flues in a rental property. Landlords typically use it to show annual compliance.
Do landlords need a gas safety certificate every year?
Landlords generally need an annual gas safety check by a Gas Safe registered engineer for rental properties with gas appliances.
Should homeowners service their boiler every year?
Annual servicing is widely recommended because it helps keep a boiler operating safely and efficiently and may also support warranty conditions.
What happens during a boiler service?
A boiler service typically includes visual checks, safety checks, combustion and flue checks where appropriate, cleaning of key components if required by the manufacturer, and confirmation that the boiler is operating correctly.
Will I get a certificate on the day?
Yes. For gas safety visits, a digital or printed certificate can be issued on the spot once the inspection is complete.
Is a boiler service the same as a gas safety certificate?
No. They are related but not identical. A gas safety certificate focuses on legal gas safety checks, while a boiler service is a maintenance visit aimed at safe and efficient performance. HeyBoiler offers a combined package.
Can you service my boiler even if it seems to be working fine?
Yes. Annual servicing is most useful before a breakdown happens. Many faults develop gradually and are easier to manage when found early.
Do you service boilers for landlords between tenancies?
Yes. This is a common time to arrange servicing and certificates so the property is ready for the next tenant.
Can a boiler service lower my energy bills?
A well-maintained boiler may run more efficiently than a neglected one, especially if components are dirty or settings are off. The exact saving depends on the system condition and usage.
Can a boiler service prevent breakdowns?
It can reduce the risk by catching wear, poor combustion, blocked components, or pressure-related problems early, but no service can guarantee a boiler will never fail.
What signs mean I should not delay a gas safety visit?
Do not delay if you notice black marks around an appliance, pilot light problems, repeated shutdowns, or anything that suggests unsafe operation. If you suspect a gas emergency, follow emergency safety guidance immediately.
Do you service combi, system, and regular boilers?
Yes. We can service the main domestic boiler types commonly found in London homes.
What if you find a fault during the service?
We explain the issue, tell you whether the boiler is safe to use, and quote separately for any recommended repair work.
Electrical Safety Certificate & PAT Testing
What is included in your electrical safety service?
The service includes an EICR by a certified electrician, PAT testing for portable appliances where requested, clear reporting with risk grading, and advice if remedial work is needed.
What is an EICR?
An EICR is an Electrical Installation Condition Report. It assesses the safety and condition of a property's fixed electrical installation.
What is PAT testing?
PAT testing checks portable electrical appliances for safety. It is commonly used for landlords, HMOs, and managed properties.
Who needs an electrical safety certificate?
Landlords, HMO operators, home buyers, and property managers often need electrical safety reporting to manage compliance and reduce risk.
Do I need both EICR and PAT testing?
Not always. EICR covers the fixed installation, while PAT testing covers portable appliances. Some properties need one, some need both.
Will I get a report with issues clearly explained?
Yes. The report includes clear findings and risk grading, along with advice if remedial work is recommended.
Can you test appliances in furnished rentals?
Yes. PAT testing is especially useful where tenants are supplied with portable appliances by the landlord or managing agent.
Can I book electrical safety and gas safety together?
Yes. If you need both, tell us when booking so we can coordinate the right services.
Emergency Boiler Breakdown
What counts as a boiler emergency?
No heating, no hot water, a boiler that will not fire up, a leak from the boiler, or a winter breakdown affecting vulnerable occupants are all common reasons to request urgent help.
What is included in an emergency boiler breakdown visit?
The visit includes rapid engineer dispatch when available, diagnosis, a temporary fix where possible, and upfront pricing for any extra work needed.
Do you offer same-day emergency boiler repair?
Often yes. Same-day response is available when schedules and location allow.
What should I do before the engineer arrives?
Check whether the thermostat is calling for heat, whether the pressure is low, whether the condensate pipe may be frozen in cold weather, and whether there is a fault code on the display. If you smell gas, do not keep testing the boiler.
Can you always fix the boiler on the first visit?
Not always. Some faults need replacement parts or further testing. Where possible we aim for a first-visit fix or a safe temporary solution.
Do you repair boilers with no hot water but heating still works?
Yes. That is a common boiler fault pattern and can be caused by several issues, including diverter valve or control problems in some systems.
Do you repair boilers with no heating but hot water still works?
Yes. This can happen because of settings, thermostat issues, air in radiators, valve problems, or system faults depending on the boiler type.
Can you help if the boiler keeps switching itself off?
Yes. Boilers can switch off due to pressure issues, thermostat faults, frozen condensate pipes, overheating, or internal component faults.
Can you diagnose fault codes on the display?
Yes. Fault codes are useful clues and help narrow down the likely issue, although final diagnosis still depends on inspection and testing.
Can you help in cold weather when the condensate pipe is frozen?
Yes. A frozen condensate pipe is a common winter issue on condensing boilers and can stop the boiler from running.
What if my boiler is leaking water?
A leak should be treated seriously. Water can damage internal components and surrounding areas, and the underlying cause can range from pressure problems to failing seals or corroded parts.
What if I smell gas near the boiler?
Treat that as an emergency. Turn off the gas supply if it is safe to do so, open windows, avoid flames or electrical switches, leave the area, and contact the National Gas Emergency Service and a Gas Safe professional.
Do you repair old boilers?
We assess older boilers where possible, but if parts are obsolete or the repair is poor value compared with replacement, we will explain your options.
Boiler Installation
What is included in a new boiler installation?
Installation includes a home assessment, boiler recommendation, removal of the old unit, installation of the new boiler, system testing, handover, warranty registration, and a gas safety check.
How do I know if I need a new boiler instead of a repair?
Replacement is often worth considering if the boiler is old, unreliable, inefficient, uneconomical to repair, or has recurring faults. The decision depends on age, condition, repair cost, and parts availability.
Can you recommend the right boiler for my home?
Yes. We assess your property, hot water demand, space, and heating system to recommend a suitable boiler type and output.
Do you remove the old boiler?
Yes. Removal of the old unit is included as part of the installation service.
Is warranty registration included?
Yes. Manufacturer warranty registration is included with new boiler installations.
Do you test the system after installation?
Yes. System testing and handover are part of the installation process so you know how the new boiler operates before the job is completed.
Can you replace my boiler with a more energy-efficient model?
Yes. Modern boilers are generally more efficient than older models, and we can recommend options that better match your home and usage.
Can I replace a combi with a system boiler or vice versa?
In many cases yes, but it depends on your home, hot water demand, pipework, cylinder space, and budget. A system change is more involved than a like-for-like replacement.
Will a new boiler help lower energy bills?
It can, especially if your current boiler is very old or inefficient. Savings vary based on insulation, controls, usage, and the condition of the wider heating system.
Can you install a boiler for a flat?
Yes, subject to access, flue position, and the suitability of the system for the property.
What should I ask before installing a new boiler?
Good questions include what boiler type suits the property, what output is needed, whether controls should be upgraded, how long the work will take, and what warranty is included.
Do I need a site survey before a quote?
For many installations, yes. A survey helps confirm boiler size, flue route, condensate disposal, controls, pipework, and any system changes needed.
Boiler Types
What are the main types of domestic boiler?
The main domestic boiler types in the UK are combi boilers, system boilers, and regular or conventional boilers. Most modern gas boilers are also condensing boilers.
What is a combi boiler?
A combi boiler heats water directly from the mains as needed and does not usually need a separate hot water cylinder, which makes it popular in many flats and smaller homes.
What is a system boiler?
A system boiler works with a separate hot water cylinder but keeps most major heating components built into the boiler, making it suitable for homes with higher hot water demand.
What is a regular or conventional boiler?
A regular boiler, sometimes called a conventional or heat-only boiler, usually works with a hot water cylinder and a cold water tank and is often found in older heating systems.
What is a condensing boiler?
A condensing boiler is designed to recover more heat from the flue gases, improving efficiency compared with older non-condensing designs.
What is an electric boiler?
An electric boiler uses electricity rather than gas to heat water for the heating system. They are less common than gas boilers but can suit some properties where gas is not available.
Which boiler type is best for a small flat?
A combi boiler is often a strong option for smaller properties with modest hot water demand because it saves space and does not usually need a cylinder.
Which boiler type is better for a larger family home?
A system or regular boiler can be better where the property has multiple bathrooms or higher simultaneous hot water demand.
Can any boiler work with smart controls?
Many modern boilers can work with smart thermostats or upgraded controls, though compatibility depends on the specific model and system setup.
Combi Boilers
What are the most common combi boiler problems?
Common combi boiler problems include no heating or hot water, low pressure, leaks, frozen condensate pipes, ignition faults, thermostat issues, and boiler lockouts.
Why does my combi boiler have hot water but no heating?
This can happen if the heating is turned off in settings, the thermostat is not calling for heat, there is a valve issue, or there is a fault affecting the heating side of the system.
Why does my combi boiler have heating but no hot water?
Possible causes include a diverter valve fault, sensor issue, control problem, or another internal component failure depending on the model.
Why does my combi boiler keep losing pressure?
Low pressure is often linked to leaks, faulty components, bleeding radiators, or other system faults. Repeated pressure loss should be investigated rather than topped up again and again.
Why does my combi boiler make banging or kettling noises?
Kettling can be linked to limescale build-up, poor circulation, trapped air, overheating, or faults affecting heat transfer and water flow.
Why does my combi boiler keep resetting or locking out?
This can happen because of ignition problems, low pressure, overheating, frozen condensate pipes, or a fault in one of the control or safety components.
What are the most common system boiler problems?
Typical issues include no heating or hot water, cylinder heating issues, pressure loss, leaks, pump faults, thermostat problems, and noisy operation.
Why is my system boiler not heating the cylinder properly?
Possible causes include a faulty cylinder thermostat, motorised valve issue, pump problem, controls fault, or poor circulation.
Do system boilers lose pressure like combi boilers?
Yes. Many sealed heating systems can lose pressure because of leaks, bleeding radiators, expansion vessel issues, or internal faults.
Are system boilers good for homes with multiple bathrooms?
They often are, because the stored hot water cylinder can support higher demand than many combi setups.
Regular / Conventional Boilers
What are the most common regular boiler problems?
Common issues include no heating, poor hot water performance, tank and valve issues, pump faults, air in the system, leaks, and control problems.
Why is my regular boiler running but the radiators stay cold?
Cold radiators can be caused by trapped air, balancing problems, valve issues, pump faults, sludge, or a boiler or controls problem.
Can I replace a regular boiler with a combi boiler?
Often yes, but it depends on the property, water pressure, hot water demand, and whether the conversion work fits your budget and goals.
Condensing Boilers
What problems are common with condensing boilers?
Common issues include frozen condensate pipes in winter, pressure loss, ignition problems, leaks, noisy operation, and general component faults.
What is a frozen condensate pipe?
A frozen condensate pipe happens when the waste pipe that carries acidic condensate from a condensing boiler freezes in cold weather, which can cause the boiler to stop working.
How do I know if the condensate pipe is frozen?
The boiler may lock out during freezing weather, and there may be gurgling or visible ice around the external condensate pipe.
Can a frozen condensate pipe cause no heating and no hot water?
Yes. On many condensing boilers, a blocked or frozen condensate line can stop the boiler from firing safely.
Electric Boilers
Do you install or service electric boilers?
If your property uses an electric boiler, tell us when booking so we can confirm the right service route. Electric systems differ from gas boiler services and safety checks.
Are electric boilers more efficient than gas boilers?
Electric boilers can be efficient at the point of use, but running costs depend heavily on electricity tariffs and the property's wider setup.
Do electric boilers need annual checks?
Regular maintenance is still sensible even though the safety regime is different from gas appliances.
Common Boiler Issues
Why is my boiler not working at all?
Common reasons include low pressure, thermostat settings, frozen condensate pipes, ignition faults, power supply issues, or a boiler lockout caused by an internal problem.
Why do I have no heating and no hot water?
This often points to a boiler-wide fault such as low pressure, ignition failure, frozen condensate, a control issue, or another safety lockout.
Why do I have no hot water but the heating works?
This pattern can be caused by a diverter valve issue in combi boilers, sensor problems, controls faults, or other internal component failures.
Why do I have hot water but no heating?
This can be caused by thermostat settings, motorised valve faults, trapped air in radiators, pump issues, or a heating-side control problem.
Why is my boiler pressure too low?
Low pressure can be caused by leaks, recently bled radiators, internal faults, or other heating system issues. The ideal operating pressure varies by appliance, but many domestic boilers run around the low 1-bar range when cold.
Why is my boiler pressure too high?
High pressure can be linked to overfilling, expansion vessel problems, or faults in the heating system. Persistently high pressure should be checked before it causes leaks or shutdowns.
Why is my boiler leaking?
Boiler leaks can be caused by excessive pressure, worn seals, corroded components, or faulty internal parts. A leak should be treated seriously and checked promptly.
Why is my boiler making a whistling, gurgling, or banging noise?
These noises can indicate kettling, trapped air, circulation problems, scale build-up, or pressure-related issues. Some operational sounds are normal, but unusual new noises deserve attention.
Why does my boiler keep switching itself off?
Possible causes include low pressure, thermostat faults, frozen condensate pipes, overheating, pump issues, or internal component failure.
Why will my boiler not ignite?
A boiler may fail to ignite because of gas supply issues, fan or gas valve faults, frozen pipes, ignition component problems, or other internal safety faults.
Why does the pilot light keep going out?
Repeated pilot light failure can indicate a fault that needs professional attention. If it will not stay lit, arrange an inspection rather than repeatedly relighting it.
Why are my radiators cold at the top?
Radiators that are cold at the top often have trapped air and may need bleeding. If the problem keeps returning, the wider system may need checking.
Why are some radiators hot and others cold?
This can happen due to balancing issues, trapped air, sludge, valve faults, or circulation problems.
Why does my thermostat not seem to control the boiler?
The issue could be with the thermostat batteries, settings, communication, wiring, zone valve, or the boiler and control interface itself.
What does boiler kettling mean?
Kettling is the term used when the boiler makes a kettle-like noise caused by overheating water or poor circulation, often linked to limescale or internal flow issues.
What should I do if my boiler shows a fault code?
Note the exact code, check the manufacturer manual if you have it, and include the code when booking. Fault codes help narrow down the problem but do not replace diagnosis.
Is a noisy boiler dangerous?
Not every noise means danger, but leaks, strong smells, repeated shutdowns, and unusual noises together can indicate a serious fault that should be checked.
Why does my boiler smell strange?
A strange smell can come from dust burning off, but if there is a gas smell or signs of unsafe combustion, stop using the appliance and seek urgent professional help.
Landlords, Tenants & Compliance
I am a landlord. Which HeyBoiler services are most relevant to me?
Landlords commonly book the combined gas safety certificate and boiler servicing package, electrical safety certificates, PAT testing where needed, breakdown visits between tenancies, and boiler replacement for aging systems.
Can I arrange certificates for a tenanted property if the tenant is home?
Yes, as long as access is agreed and someone responsible is available to let the engineer in and provide safe access to the appliances.
Can tenants book a boiler repair directly?
Tenants can contact us, but in many rental situations the landlord or managing agent should approve chargeable repair work.
What if my tenant has no heating or hot water?
Treat it as urgent. Heating and hot water failures should be dealt with quickly, especially in cold weather or where vulnerable occupants are affected.
Can I book between tenancies to get the property ready?
Yes. This is a smart time to schedule servicing, safety checks, and any needed remedial work before new tenants move in.
Repair vs Replace
Is it better to repair or replace an old boiler?
That depends on age, reliability, efficiency, cost of repair, and parts availability. If faults are recurring or repairs are becoming uneconomical, replacement may offer better long-term value.
How old is too old for a boiler?
There is no single age that makes replacement mandatory, but older boilers are often less efficient, more fault-prone, and harder to repair because parts may be discontinued.
Can a leaking boiler be repaired or does it need replacing?
Sometimes a leak can be repaired, but the answer depends on where the leak is, how severe it is, and the overall age and condition of the appliance.
When should I replace rather than keep topping up boiler pressure?
If pressure keeps dropping, do not treat topping up as a permanent fix. Repeated pressure loss usually means an underlying leak or component fault that should be diagnosed.
Can a boiler service tell me if replacement is near?
Often yes. A service can reveal wear, poor combustion, corrosion, or repeat risk factors that help you decide whether to keep repairing or plan a replacement.
Cost, Value & Savings
What affects the cost of boiler repair?
Repair cost depends on diagnosis time, replacement parts, boiler brand and age, ease of access, and whether the fault is isolated or part of a wider system issue.
What affects the cost of a new boiler installation?
Cost depends on boiler type and output, whether the job is a straight swap or a system conversion, flue route, controls, filters, pipework changes, and disposal of the old unit.
Is annual boiler servicing worth it?
For most households, yes. It helps manage safety, efficiency, reliability, and early fault detection, and it may also support manufacturer warranty terms.
Can better controls improve heating efficiency?
Yes. Modern room thermostats, timers, and smart controls can help reduce waste by running the heating more precisely.
Will bleeding radiators help heating performance?
It can if air is trapped in the system. Cold tops on radiators are a common sign that bleeding may help restore heat output.
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