Adam Stapley Plumbing · Epsom
Heating & Boiler Advice Centre
Straightforward boiler, heating and hot water advice from a local Gas Safe engineer with over 25 years’ experience.
Whether your boiler has stopped working, you are deciding whether to repair or replace it, or you simply want to look after your heating system properly, this guide brings together the questions I get asked most often by homeowners across Epsom and the surrounding areas.
Choose a heating or boiler topic
This page is designed as a proper advice hub rather than a sales page. Use the sections below to understand common faults, when to call an engineer, and which service page is most relevant.
🔥 Boiler replacement
Advice on old boilers, repair costs, efficiency, warranties, boiler types and when replacement makes sense.
Read replacement advice🛠 Boiler repairs
Low pressure, no heating, no hot water, leaks, noises and common fault symptoms explained in plain English.
Read repair advice🧰 Boiler servicing
What a boiler service includes, why annual servicing matters and how it helps keep your heating safe and reliable.
Read servicing advice🌡 Heating systems
Radiators, filters, pumps, controls, balancing, sludge and how to improve heating system performance.
Read heating advice💧 Hot water
Advice on cylinders, unvented hot water, immersion heaters, shower pumps and poor hot water performance.
Read hot water advice⚠ Gas safety
Gas Safe registration, carbon monoxide, landlord certificates and when gas appliances should be checked.
Read gas safety adviceBoiler replacement advice
A boiler replacement is one of the bigger decisions you can make in your home. Most people start thinking about it when the existing boiler becomes unreliable, repair costs start building up, or the heating and hot water no longer feel as dependable as they should.
The right answer is not always “replace it”. Sometimes a sensible repair and a proper service can keep a boiler going. But if the boiler is old, inefficient, regularly breaking down or fitted on a poor system, replacement can be the more cost-effective choice over the next few years.
How do I know if my boiler needs replacing?
Common signs include frequent breakdowns, expensive parts, repeated pressure loss, poor hot water, noisy operation, visible corrosion, difficulty getting parts, and rising gas usage. Age matters, but reliability and repair history matter more. A ten-year-old boiler that has been maintained well may still have life left in it. A newer boiler on a dirty or poorly installed system can still cause problems.
Should I repair or replace my boiler?
I usually look at four things: the age of the boiler, the likely repair cost, the condition of the heating system and how long the customer plans to stay in the property. A one-off repair on a generally sound boiler may be worthwhile. Repeated faults, major component failures or safety concerns may point towards replacement.
Which type of boiler is best?
It depends on the property. A combi boiler can be ideal for many homes because it provides heating and hot water from one appliance without separate tanks. A system boiler may suit homes with higher hot water demand and an unvented cylinder. A heat-only boiler may be suitable where there is an existing traditional system with tanks and a hot water cylinder.
Is a Worcester Bosch boiler worth considering?
Worcester Bosch boilers are a common choice for many replacement jobs because they are well known, widely supported and familiar to engineers. The correct model and installation quality matter just as much as the badge on the front. A good boiler fitted badly can still lead to problems.
What should be included with a good boiler installation?
A proper installation should include correct sizing, safe flue positioning, system cleaning where needed, inhibitor, magnetic filter where appropriate, suitable controls, correct condensate arrangements, commissioning, Gas Safe notification and clear handover. The hidden pipework and preparation are just as important as the boiler on the wall.
Thinking about a new boiler?
See my dedicated boiler replacement page for local installation advice and quotations around Epsom.
Boiler Replacement EpsomBoiler repair advice
Boiler faults can be frustrating because the symptoms are often similar even when the causes are different. No heating, no hot water, pressure loss or a fault code can be caused by a range of issues. A proper diagnosis is important before replacing parts.
Why is my boiler losing pressure?
Repeated pressure loss usually means the water in the sealed heating system is escaping somewhere or the boiler is discharging through a safety component. Causes can include a small radiator leak, pipework leak, pressure relief valve issue, expansion vessel fault, automatic air vent leak or a heat exchanger problem. Topping it up every few days is not a fix.
Why have I got no heating but still have hot water?
This may be related to controls, motorised valves, pumps, diverter valves, wiring, thermostats or boiler components depending on the type of system. It is a common problem but needs testing rather than guessing.
Why have I got hot water but no heating?
On a combi boiler it may be a diverter valve or control issue. On a system or heat-only boiler it may be a pump, motorised valve, programmer or thermostat issue. Radiator problems can also be linked to air, sludge or balancing.
Why is my boiler making a banging or kettling noise?
Banging, rumbling or kettling can be caused by poor circulation, sludge, scale, pump problems, blocked heat exchangers or overheating. It is worth investigating early because circulation problems can shorten boiler life.
Can I use a leaking boiler?
A leak should not be ignored. Water inside a boiler can damage electrical components and may indicate a more serious fault. If the leak is significant, turn the appliance off and arrange for it to be checked.
Why does my boiler keep locking out?
A lockout means the boiler has detected a fault and shut itself down. It could be ignition, flame detection, overheating, circulation, condensate, fan, gas supply or sensor related. Repeated resets are not recommended because the boiler is locking out for a reason.
Need a boiler fault diagnosed?
For local boiler repair help, visit the repair page or get in touch.
Boiler Repair EpsomBoiler servicing advice
Annual servicing is one of the simplest ways to look after a boiler. A service is not just a quick visual check. It should confirm safe operation, check the condition of key components, test combustion where appropriate and identify early warning signs before they become breakdowns.
How often should a boiler be serviced?
Most domestic boilers should be serviced once a year. Annual servicing is commonly required for manufacturer warranties and is strongly recommended for safety, reliability and efficiency.
What is included in a boiler service?
A proper service will usually include visual inspection, flue checks, ventilation checks where relevant, gas pressure or rate checks where appropriate, combustion analysis, safety device checks, condensate checks, case seal inspection, controls check and advice on any issues found.
Can servicing prevent breakdowns?
It cannot guarantee a boiler will never break down, but it can spot problems early. Blocked condensate traps, worn seals, poor combustion readings, leaks, pressure issues and signs of overheating can often be picked up during routine maintenance.
Is a landlord gas safety check the same as a boiler service?
No. A landlord gas safety check focuses on safety and legal compliance for rented properties. A boiler service is a maintenance visit. They can often be done at the same appointment, but they are not the same thing.
Due a boiler service?
Book a local boiler service with a Gas Safe registered engineer.
Boiler Servicing EpsomHeating system advice
The boiler is only one part of the heating system. Radiators, pumps, valves, filters, pipework, controls and water quality all affect performance. Many boiler problems are actually system problems.
Why are some radiators cold?
Cold radiators may be caused by trapped air, sludge, stuck radiator valves, poor balancing, pump issues or pipework restrictions. If one radiator is cold at the top it may need bleeding. If it is cold at the bottom, sludge may be a factor.
What is a magnetic filter?
A magnetic filter helps collect magnetic debris from the heating water. This can reduce the amount of sludge reaching the boiler and help protect components. It is not a substitute for good installation practice or proper system cleaning, but it is often a sensible addition.
Do I need a power flush?
Not every system needs a power flush. Some systems need targeted cleaning, chemical treatment or a Magnacleanse-style clean. The right approach depends on the age of the system, symptoms, water quality and condition of radiators and pipework.
Why does my heating take a long time to warm up?
Slow heating can be caused by poor circulation, undersized radiators, old controls, incorrect boiler settings, sludge, pump issues or a system that needs balancing. Improving controls and water quality can make a noticeable difference.
Are smart thermostats worth it?
Smart thermostats can be useful if they help you control the heating better and avoid wasting energy. The best control is the one the household actually uses properly. Installation quality and correct setup matter.
Hot water and cylinder advice
Hot water problems can come from the boiler, cylinder, controls, valves, pumps, immersion heater or water supply. The setup in your home makes a big difference, so diagnosis depends on whether you have a combi boiler, hot water cylinder, unvented cylinder or pumped system.
Why is my hot water not getting hot enough?
Possible causes include boiler faults, cylinder thermostat problems, motorised valve issues, scale, immersion heater failure, blending valve faults or poor flow through the system. On combi boilers it may be linked to plate heat exchanger or flow sensor problems.
What is an unvented cylinder?
An unvented cylinder stores hot water under mains pressure and can provide strong hot water performance when correctly specified and installed. It must be installed and maintained by someone with the correct unvented qualification.
Why is my shower pump noisy?
Shower pumps can become noisy due to air, poor installation, blocked filters, worn bearings, incorrect pipework or water supply issues. A pump should be installed in line with manufacturer instructions and suitable flange arrangements where required.
Can an immersion heater be replaced?
In many cases, yes. The cylinder type, access, wiring, condition of the boss and whether it is vented or unvented all matter. Older cylinders can be awkward, and there is always a risk of damage if fittings are seized.
Hot water problem?
For unvented cylinders, immersion heaters and hot water issues, get in touch for advice.
Unvented Hot WaterGas safety advice
Gas appliances should always be treated seriously. If you smell gas, suspect carbon monoxide, or believe an appliance is unsafe, do not ignore it. Gas work should only be carried out by a Gas Safe registered engineer who is qualified for the type of appliance being worked on.
What does Gas Safe registered mean?
Gas Safe registration means an engineer is legally registered to carry out gas work in the categories they are qualified for. You should always check that the engineer is registered and suitably qualified for the appliance.
What are signs of carbon monoxide risk?
Warning signs can include staining around appliances, lazy yellow flames on certain appliances, frequent headaches or sickness at home, and carbon monoxide alarms sounding. Carbon monoxide cannot be seen or smelt, so alarms and proper servicing are important.
Do landlords need annual gas safety certificates?
Landlords are responsible for arranging gas safety checks for rented properties. The check must be carried out by a Gas Safe registered engineer and recorded correctly.
Can I do gas work myself?
Gas work should be carried out by a suitably qualified Gas Safe registered engineer. DIY gas work can be dangerous and may invalidate insurance or warranties.
Need a gas safety certificate?
Visit the gas safety page for landlord and homeowner gas checks around Epsom.
Gas Safety CertificatesWinter boiler advice
Most boiler problems show up when the heating is working hardest. A system that has seemed fine all summer can struggle once colder weather arrives. A little preparation can reduce the chance of breakdowns.
What should I check before winter?
Check the boiler pressure, test the heating before the first cold spell, bleed radiators if needed, make sure the thermostat works, check carbon monoxide alarms and book a service if it is overdue.
What is a frozen condensate pipe?
Condensing boilers discharge condensate through a pipe. In cold weather, external condensate pipes can freeze and cause the boiler to lock out. The pipe route, insulation and installation quality all affect the risk.
Should I turn the heating on occasionally in autumn?
Yes, it is sensible to test the heating before you really need it. This gives you time to deal with stuck valves, pressure problems or boiler faults before the busy winter period.
Heating and boiler FAQs
These short answers are included to help customers quickly understand common boiler and heating questions. For anything safety-related, always use a qualified engineer.
How long does a boiler last?
Many boilers last around 10–15 years, but this depends on installation quality, servicing, system cleanliness and how hard the boiler has worked.
Is low boiler pressure dangerous?
Low pressure is not usually dangerous by itself, but repeated pressure loss means there is a fault that should be investigated.
Can I top up my boiler?
Some homeowners can top up pressure using the filling loop, but repeated topping up is a sign something is wrong.
Why are my radiators noisy?
Noisy radiators can be caused by air, poor circulation, sludge, expansion noises or balancing issues.
Do I need a magnetic filter?
A magnetic filter is often a good idea, especially on older systems or new boiler installations, but it should be part of a wider water-quality approach.
What is inhibitor?
Inhibitor is a chemical added to heating water to help protect against corrosion and sludge.
Why does my boiler smell?
If you smell gas, call the emergency gas number and do not use electrical switches. Other smells may be dust, overheating or condensate-related, but should be checked if unusual.
Should I leave heating on low?
It depends on the property, insulation and routine. Good controls usually matter more than one fixed rule.
Why is my hot tap flow poor?
Poor flow can be caused by taps, filters, scale, pipework, valves, cylinders or combi boiler restrictions.
Can a boiler be moved?
Often yes, but flue route, gas pipe sizing, condensate drainage, access and regulations all need checking.
What boiler size do I need?
Boiler sizing depends on heat loss, hot water demand and the type of system. Bigger is not automatically better.
Can you service my boiler and do a gas certificate together?
In many cases yes, a service and landlord gas safety check can be arranged during the same visit.
Important service pages
This advice centre supports the main service pages across the website. If you already know what you need, use the links below.
Still need heating or boiler advice?
If you cannot find the answer you are looking for, it is often easier to speak to an experienced engineer. I cover Epsom and the surrounding areas for boiler replacement, repairs, servicing, gas safety and heating work.