Frequently Asked Questions

We are based in Bordon (GU35) and cover Hampshire, Surrey and Sussex, including Headley, Liphook, Petersfield, Haslemere, Hindhead, Grayshott, Liss, Alton, Farnham and the surrounding villages. If you are not sure whether we reach you, call 01428 727222 and we will confirm.

Yes. Miller & Sons is Gas Safe registered, and we are also OFTEC registered for oil, members of the Water Industry Approved Plumbers Scheme (WIAPS), and hold City & Guilds qualifications in plumbing and electrical work. All gas work meets the legal safety standards required by UK law.

Yes. We provide a 24/7 emergency call-out service, 365 days a year, for heating, boiler and plumbing emergencies across our coverage area. Call us as soon as a problem develops and we will respond as quickly as we can.

Miller & Sons is a family-run business that has served Bordon and the surrounding area for over 15 years, taking on both domestic and commercial work from minor repairs through to full installations and system upgrades.

Yes. All quotes are free of charge and provided with no obligation. They are valid for 30 days and based on the information available at the time, and any change in scope is discussed and agreed before extra work is carried out.

We accept bank transfer and card payments. A deposit of up to 50 per cent of the quotation may be required before larger works begin to secure the booking and cover initial materials, with the balance due on completion unless agreed otherwise in writing.

Yes. All labour comes with a 12 month workmanship guarantee covering defects due to poor workmanship, and materials are covered by the manufacturer warranty where applicable. We are also insured for public liability up to £10 million.

Usually 2–3 days if pipework, location, or system type needs changing.

Yes, typically for most of the day while the old system is removed and the new one is fitted.

Combi boiler – most homes, one bathroom. System boiler – larger homes with multiple bathrooms. Regular boiler – older homes with loft tanks.

It depends on: number of bathrooms. Household size. Water demand. An installer will usually calculate the correct output (kW).

£3,000 – £6,000+.

Possible extras include: new pipework. Flue upgrades. Chemical system flush. Thermostat upgrades.

Once every 12 months is recommended.

Check pressure occasionally. Bleed radiators if needed. Book annual service.

A boiler service is a routine check carried out by a Gas Safe registered engineer to ensure your boiler is safe, efficient, and working properly.

Once every 12 months is recommended by most manufacturers and engineers.

Prevent breakdowns. Improve energy efficiency. Keep your home safe from gas or carbon monoxide leaks. Maintain your warranty.

Usually 60 - 90 minutes, depending on the boiler condition and type and location and access.

An engineer typically: checks internal components. Tests gas pressure and flow. Inspects flue and ventilation. Cleans key parts if needed. Checks for leaks or corrosion. Runs safety tests.

Yes, briefly. The boiler is switched off for safety during inspection and testing.

Yes. Regular servicing often costs less than a single breakdown repair and helps extend the boiler’s lifespan and adheres to your manufacturers warranty cover requirements.

An unvented cylinder is a sealed hot water system fed directly from the mains, providing high-pressure hot water without a cold water storage tank.

Yes. In the UK, installers must hold a recognised certification such as: g3 (Building Regulations Part G3) qualification. This ensures safe installation of pressurised systems.

Yes. Installation must comply with Part G3 of the Building Regulations. You must either: be registered with a competent person scheme, or. Notify Building Control before installation.

Strong, balanced water pressure. No loft tank required (saves space). Multiple outlets can run simultaneously. Cleaner water (no stored tank contamination risk).

High pressure = potential safety hazard if incorrectly installed. Requires safety devices (temperature & pressure relief valves). Needs annual servicing.

Key mandatory components include: temperature & Pressure Relief Valve (T&P valve). Expansion vessel or internal air gap. Check valve (non-return valve). Pressure reducing valve. Discharge pipework (correctly sized and routed).

Adequate mains pressure (typically 1.5 bar minimum, ideally 2–3 bar). Good flow rate (usually 20–25 litres. Min recommended). If supply is poor, performance will suffer.

Yes, including: gas boilers. Electric immersion heaters. Heat pumps. Solar thermal systems.

Typically 1–2 days depending on complexity. Longer if upgrading pipework or electrics.

Yes , annually recommended: check safety valves. Inspect expansion vessel. Verify pressure settings.

Airing cupboard. Utility room. Garage. It must be: accessible for servicing. Installed on a suitable load-bearing surface.

Critical for safety: must terminate safely outside. Visible discharge point preferred. Sized and routed according to G3 guidance. Must not be blocked or restricted.

No , they rely on mains pressure, so no stored cold water backup.

Generally quiet, though: expansion vessel issues can cause noise. Incorrect pressure settings may lead to vibration.

Incorrect discharge pipe sizing. Missing or incorrectly fitted safety valves. Poor expansion vessel setup. Inadequate mains supply assessment.

Typical ranges: cylinder: £500–£1,500. Installation: £500–£3,000+. Depends on size, brand, and system complexity.

Check the basics first: power supply, thermostat settings, pressure gauge, and whether the gas. Electric supply is on. If everything looks fine, contact a qualified heating engineer.

Common causes include low pressure, frozen condensate pipe, power cut, faulty thermostat, or internal component failure.

Low pressure usually means there’s not enough water in the system. It often needs repressurising using the filling loop.

A lockout is a safety feature that shuts the boiler down when it detects a fault, such as no flame, pressure issues, or blocked components.

You can check simple issues like pressure and power, but internal repairs should always be done by a Gas Safe registered engineer.

Banging, whistling, or gurgling may indicate air in the system, limescale build up, or low water pressure.

Boiler pressure. Thermostat settings. Electricity and gas supply. Any error codes on the display. Frozen condensate pipe (in cold weather).

Simple fixes may take under an hour. More complex faults or parts replacement can take longer if parts need ordering.

Yes, especially in winter or if you have no heating or hot water. It’s recommended to arrange an urgent repair.

Annual servicing, keeping pressure at the correct level, bleeding radiators, and ensuring good ventilation can help prevent issues.

An air source heat pump is a low-carbon heating system that extracts heat from the outside air and uses it to heat your home and hot water.

It works like a fridge in reverse: absorbs heat from outside air. Compresses it to increase temperature. Transfers heat into your heating system (radiators, underfloor, hot water).

Yes. A properly designed system can provide: full central heating. Hot water supply. Correct sizing and system design are critical for performance.

Yes, even in UK winters. They can operate in temperatures as low as -15°C, although efficiency drops slightly in colder conditions.

They use electricity, but are very efficient: typically produce 2–4 units of heat for every 1 unit of electricity. Much more efficient than direct electric heating.

It depends on: electricity vs gas prices. Insulation levels. System design.

Best suited for homes that: are well insulated. Have adequate radiator size or underfloor heating. Have space for a hot water cylinder. A professional heat loss survey is essential.

Outdoor unit (installed externally). Indoor cylinder (for hot water). Upgraded radiators (in some cases). Good insulation. The unit must have space around it for airflow and sit on a solid base.

They produce around 60–65 dB at maximum output (similar to normal conversation). Modern systems are generally quiet when correctly installed.

Yes: annual servicing recommended. Checks include filters, refrigerant, and system pressures.

Typically 15–20 years with proper maintenance.

Yes: lower carbon emissions than gas or oil heating. Can reduce household carbon footprint significantly. Even greener when paired with renewable electricity.

Yes: boiler Upgrade Scheme (BUS) offers up to £7,500 towards installation (subject to eligibility).

Not strictly "better", just different: heat pumps = low temperature, constant heat. Boilers = high temperature, on. Off heating. Heat pumps require a different way of heating your home (low & steady).

Higher upfront cost. May require radiator upgrades. Works best in well-insulated homes. Slower heat-up compared to boilers.

"They don’t work in winter" - They do. "They can’t heat radiators" - They can (if sized correctly). "They’re noisy" - Modern units are relatively quiet.

Undersized system. Poor insulation assessment. Incorrect radiator sizing. Bad positioning of outdoor unit.

A full refurbishment can include removing old fittings, plumbing adjustments, new bathroom suite installation, tiling, flooring, lighting, and finishing touches.

Most bathroom refurbishments take around 5–14 working days, depending on the size of the room and the complexity of the work.

Yes, we can manage the full project including plumbing, electrical work, tiling, plastering, and installation to provide a complete service.

Absolutely. You can supply your own materials or we can help you choose and source everything you need.

We recommend clearing the bathroom and ensuring easy access to the area. We’ll handle the rest, including protection of surrounding spaces.

Yes, there may be short periods without facilities while work is being carried out. We aim to minimise disruption wherever possible.

Costs vary depending on the size of the bathroom, chosen fittings, and level of work required. A detailed quote is provided before work begins.

Yes, we also handle smaller jobs such as replacing taps, toilets, showers, or updating individual fixtures.

Yes, we can offer advice on layout, style, space-saving solutions, and modern design options.

Yes, all workmanship is guaranteed for your peace of mind, and manufacturer warranties apply to supplied products.

We cover all general plumbing services including leaks, tap repairs, toilet repairs, pipework, radiator issues, sink and bath installations, and more.

Yes, most plumbing issues such as burst pipes, major leaks, and blocked toilets can be treated as emergencies and prioritised.

Common signs include damp patches, mould, reduced water pressure, unusual water bills, or the sound of running water when nothing is on.

Yes, these are common repairs and are usually quick to diagnose and fix, often involving worn washers or faulty internal parts.

Yes, we install sinks, toilets, showers, baths, taps, and full bathroom suites, including replacements and upgrades.

Turn off the main water supply if possible, isolate affected appliances, and contact a qualified plumber immediately.

Small repairs can take under an hour, while installations or more complex issues may take several hours or longer.

Costs vary depending on the issue, parts required, and time needed. We usually provide a quote before starting any work.

Yes, regular maintenance can help prevent leaks, blockages, and long-term damage to your plumbing system.

Minor tasks like tightening fittings may be safe, but most plumbing work should be handled by a qualified professional to avoid damage or leaks.

An oil-fired boiler is a heating system that burns heating oil to provide: central heating. Hot water. It is commonly used in off-grid homes without access to mains gas.

Oil boilers are ideal for: rural or off-grid properties. Homes without gas supply. Larger properties needing high heat output.

Typical UK price ranges: £4,000 - £5,000 - basic like-for-like replacement. £5,000 – £10,000 - average installation.

Usually 1–2 days for a standard replacement. Longer if: pipework or system upgrades are required.

A full installation typically includes: removal of old boiler. New boiler fitting. Flue installation. System connection. Controls setup. Safety testing and commissioning.

Not always. You may need a new tank if: the existing tank is damaged or leaking. It does not meet current regulations. It is too small for your heating demand.

Yes, when installed and maintained properly. Safety depends on: correct installation. Regular servicing. Proper ventilation and fuel storage.

Installers should be registered with: oFTEC. This ensures they are trained to install and service oil systems safely.

Powerful heating for larger homes. Reliable in rural areas. Long lifespan (15–20 years). High heat output.

There are no immediate bans on existing systems. However, the UK is encouraging low-carbon alternatives over time. Future regulations may favour heat pumps.

Yes, this is very common. A like-for-like swap is usually: faster. Cheaper. Less disruptive.

Yes, but it requires: oil tank installation. New pipework. Proper site assessment.

Yes. Oil boilers: perform well in freezing conditions. Are commonly used in colder rural areas.

Modern condensing oil boilers can reach: around 90%+ efficiency when properly installed.

Yes, at least once a year to: maintain efficiency. Prevent breakdowns. Ensure safe operation.

Frequent breakdowns. Rising fuel bills. Poor heating performance. Loud operation or soot build-up.

Often yes: better efficiency. Lower fuel usage. Fewer repair costs.

Minimal disruption for replacements, but more work if: new tank is installed. Pipework needs upgrading. System is being redesigned.

A powerflush is a deep cleaning process for your central heating system. It removes sludge, rust, and debris that build up inside radiators, pipes, and the boiler.

A specialist machine pumps water and cleaning chemicals at high velocity through the heating system to: break down sludge. Flush out debris. Restore proper water flow.

You may need one if you notice: cold spots on radiators. Radiators not heating properly. Noisy boiler or pipes. Slow heating response. Frequent boiler breakdowns.

Yes. It can: improve heat distribution. Help radiators heat up faster. Reduce strain on the boiler. Improve system efficiency.

Typical prices: £600 – £1,000+. Cost depends on: number of radiators. System condition. Property size.

Usually takes one day.

A standard service includes: connection of flushing machine. Chemical cleaning of system. Individual radiator flushing. System balancing. Addition of inhibitor after cleaning.

When done correctly by a professional, it is safe. However, poor execution can: damage old pipework. Cause leaks in weak radiators. Stir up debris temporarily.

Not always. It helps with: sludge-related issues. But it won’t fix: faulty boilers. Broken pumps. Electrical control issues.

No: bleeding radiators removes trapped air. Powerflushing removes sludge and debris from the whole system.

Typically every 5–10 years. Or when symptoms appear.

No, when done properly. In fact, it: reduces stress on the boiler. Helps extend its lifespan.

Yes, in many cases: radiators heat more evenly. Rooms warm up faster. Cold spots are removed.

Typically: cleaning chemicals to break down sludge. Neutralising agents. Corrosion inhibitor added after flushing.

No. It’s usually needed when: system is old or poorly maintained. Heating performance is reduced. A new boiler is being installed.

Yes, most manufacturers recommend it. It helps: protect the new boiler. Maintain warranty conditions.

Radiators warm at top but cold at bottom. Heating takes longer than usual. Boiler keeps cutting out. Dirty water when bleeding radiators.

A central heating system heats your home from one central source (usually a boiler or heat pump) and distributes warmth through: radiators. Underfloor heating. Hot water system.

Most systems work by: heating water in a boiler or heat pump. Pumping hot water through pipes. Radiators release heat into rooms. Water returns to be reheated.

Common types include: gas central heating systems. Oil-fired central heating systems. Electric systems. Renewable systems (e.g. heat pumps).

Typical ranges: £3,000 – £5,000 - small system or replacement. £5,000 – £8,000 - average full installation. £8,000 – £12,000+ - larger or complex systems. Costs vary depending on property size and system type.

1–3 days for boiler replacement. 3–7 days for full central heating system installation. Longer for full property upgrades.

A full install may include: boiler or heat source installation. Radiators and pipework. Pump and controls. Thermostats and smart controls. System commissioning and testing.

Common causes: air trapped in system. Sludge or debris build-up. Faulty pump or valves. Poor system balance. A powerflush or system service may be needed.

A powerflush is a deep clean of your heating system that removes: sludge. Rust. Debris. It helps improve efficiency and radiator performance.

Possible causes: leak in the system. Faulty pressure relief valve. Expansion vessel issue. Radiator or pipework leaks.

Typically 10–15 years. Well-maintained systems may last longer.

Yes, when properly installed and maintained. Regular servicing helps ensure: safe operation. Efficient performance. Reduced risk of breakdowns.

Boiler: once per year. System checks: every 1–2 years.

Yes. Common upgrades include: new boiler installation. Smart thermostats. Radiator upgrades. System flushing.

Install a modern condensing boiler. Use smart heating controls. Improve insulation. Balance radiators. Regular servicing.

Cold radiators. Strange noises from boiler. Slow heating response. Rising energy bills. Frequent system breakdowns.

Yes, if your pipework and radiators are in good condition. However, older systems may benefit from full upgrades.

System balancing ensures: all radiators heat evenly. Water flow is correctly distributed. The system runs efficiently.

Yes: better temperature control. Lower energy bills. Remote control via apps.