Heat-only boilers remain particularly relevant to larger houses, older heating systems and properties where several bathrooms or hot-water outlets may be used.

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APN Boilers helps homeowners find experienced heating professionals who can assess the existing system, calculate the required boiler output and recommend a suitable heat-only boiler installation.

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What Is a Heat-Only Boiler?

 

A heat-only boiler heats water for the central-heating system. That heated water circulates through the radiators and can also pass through a coil inside a separate hot-water cylinder.

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The boiler does not provide instantaneous domestic hot water in the way a combi boiler does.

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Instead, hot water is heated and stored within the cylinder, ready for use at baths, showers and taps.

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A traditional open-vented heat-only system may include:

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• Heat-only boiler

• Hot-water cylinder

• Central-heating pump

• Cold-water storage cistern

• Feed-and-expansion cistern

• Motorised valves

• Room thermostat

• Cylinder thermostat

• Heating and hot-water programmer

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Vaillant explains that an open-vent heat-only system uses a feed-and-expansion tank to maintain the heating-system pressure, whereas a system boiler normally incorporates a pressurised heating circuit and internal expansion vessel.

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Heat-Only, Regular and Conventional Boilers

 

The terms heat only, regular and conventional usually describe the same basic boiler type.

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Manufacturers use different terminology:

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• Worcester Bosch describes its Greenstar Ri as a regular boiler.

• Vaillant refers to its equivalent product as an open-vent or heat-only boiler.

• Ideal uses the description heat-only boiler.

• Baxi uses both heat-only and conventional boiler.

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The underlying principle is that the boiler works with a separate hot-water cylinder rather than producing instantaneous hot water.

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However, not every heat-only boiler must operate on a traditional open-vented system. Some can be incorporated into a sealed heating arrangement when the required external components are provided.

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The installer should therefore assess the actual system rather than relying solely on the boiler description.

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How Does a Heat-Only Boiler Work?

 

When the property requires heating, the boiler heats water that is circulated through the radiators.

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When hot water is required, a motorised valve directs heated primary water through a coil inside the hot-water cylinder. Heat transfers through the coil and warms the domestic water stored within the cylinder.

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The room thermostat, cylinder thermostat and programmer determine when the boiler operates.

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The system can normally be programmed for:

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• Heating only

• Hot water only

• Heating and hot water together

• Separate morning and evening periods

• Constant operation

• Frost-protection periods

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Modern controls can provide more detailed scheduling, separate heating zones and app-based operation.

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Is a Heat-Only Boiler Suitable for Your Home?

 

A heat-only boiler may be appropriate where:

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• The existing property already has a conventional heating system

• The hot-water cylinder remains serviceable

• The home has several bathrooms

• Several hot-water outlets may be used together

• The existing radiator system is open vented

• The internal pipework may not suit conversion to a pressurised system

• Mains-water pressure or flow is unsuitable for a combi

• The homeowner wants to minimise changes to the existing system

• An immersion-heater backup is valuable

• Solar thermal or another cylinder-based technology is being considered

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Ideal positions heat-only boilers as a traditional heating solution that can work particularly well in larger properties. Baxi also identifies heat-only boilers as an option for homes where water pressure may make other arrangements less suitable.

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A heat-only boiler may be less attractive where the property is small, storage space is limited or the homeowner wants to remove the hot-water cylinder and roof tanks.

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Benefits of a Heat-Only Boiler

 

Stored Hot Water

The cylinder stores a quantity of hot water that can be delivered when required.

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This can make a heat-only boiler more suitable than a standard combi for homes with several bathrooms or simultaneous demand.

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Suitable for Existing Traditional Systems

Many older properties already have open-vented radiators, tanks and a hot-water cylinder.

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Replacing one heat-only boiler with another can avoid the extensive alterations involved in converting the complete system.

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Potentially Suitable for Older Pipework

A traditional open-vented heating system operates differently from a sealed pressurised system.

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Where older radiators or pipework are unsuitable for increased pressure, retaining the existing arrangement may reduce the risk of leaks.

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The system should nevertheless be inspected, cleaned and tested before the new boiler is connected.

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Immersion-Heater Backup

Many hot-water cylinders contain an electric immersion heater.

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This can provide hot water if the boiler develops a fault or is switched off during the summer.

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Multiple Hot-Water Outlets

A correctly sized cylinder can supply several taps, showers and baths.

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The actual performance will depend on the cylinder type, stored-water capacity, pipework and water pressure.

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Compatible With Different Cylinders

Heat-only boilers may be used with:

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• Traditional vented cylinders

• Unvented cylinders where appropriately designed

• High-recovery cylinders

• Twin-coil cylinders

• Solar thermal cylinders

• Thermal stores

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The cylinder and boiler must be selected as one coordinated system.

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Disadvantages of a Heat-Only Boiler

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More Equipment Is Required

A conventional system may require a boiler, cylinder, tanks, pump, valves and controls.

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This occupies more space than a combi boiler.

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Hot Water Can Run Out

The cylinder stores a limited quantity of hot water.

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Once that supply has been used, the boiler must reheat the cylinder before the full amount is available again.

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Heat Is Lost From the Cylinder

Even a well-insulated cylinder loses some stored heat.

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Modern cylinders are generally better insulated than older models, but storage losses cannot be removed completely.

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More Components Can Require Maintenance

Pumps, motorised valves, thermostats, expansion arrangements and cylinders may eventually need servicing or replacement.

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Roof-Space Tanks May Be Required

A traditional open-vented arrangement normally retains tanks in the loft.

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These must be properly supported, insulated and protected against freezing.

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Heat-Only Boiler vs Combi Boiler

 

A combi boiler provides heating and instantaneous hot water from one appliance.

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A heat-only boiler works with a separate cylinder and potentially additional tanks.

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Consideration   /   Heat-only boiler Combi boiler

Hot-water supply - Stored in a cylinder - Heated on demand

Separate cylinder - Normally required - Not normally required

Loft tanksMay be required - Not normally required

Multiple bathrooms - Often well suited - Depends heavily on mains flow

Space required - More - Less

Hot-water backup - Possible through immersion - Usually no stored backup

Hot water running out - Possible - No stored supply to exhaust

Conversion work - Limited for like-for-like replacement - Can be extensive

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A combi may be suitable for a smaller property with one main bathroom and a strong mains-water supply.

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A heat-only boiler may provide a more dependable solution where the home has several bathrooms, an existing cylinder or traditional low-pressure pipework.

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Heat-Only Boiler vs System Boiler

 

Heat-only and system boilers both work with a separate hot-water cylinder.

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The principal difference concerns the central-heating components and pressure arrangement.

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A system boiler normally incorporates components such as the circulation pump and expansion vessel within the boiler casing. It typically operates as a sealed, pressurised heating system.

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A traditional heat-only boiler relies on separately installed components and may use a feed-and-expansion tank in the loft.

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Consideration - Heat-only boiler - System boiler

Hot-water cylinder - Required - Required

Expansion arrangement - Often external or open vented - Usually incorporated and sealed

Circulation pump - Often external - Usually incorporated

Loft feed tank - Common on traditional systems - Not normally required

Existing older system - Frequently suitable - May require conversion

Installation pipework - More external components - More components inside boiler

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Vaillant confirms that both arrangements use stored hot water, but system boilers operate through a pressurised heating circuit while traditional heat-only systems use a feed-and-expansion tank.

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What Is the Best Heat-Only Boiler?

 

There is no single best heat-only boiler for every property.

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The best choice depends on:

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• Calculated heat loss

• Existing system type

• Required output

• Available installation space

• Flue position

• Cylinder size

• Heating controls

• Manufacturer support

• Installer experience

• Guarantee conditions

• Total installed cost

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Several leading current models are worth comparing.

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Leading Gas Heat-Only Boilers

 

Boiler - Available considerations - Particularly relevant for:

Worcester Bosch Greenstar Ri - Compact regular boiler with several outputs and guarantees up to ten years on qualifying installations - Small, medium and larger homes requiring cupboard installation

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Vaillant ecoTEC Plus Open Vent - Flexible output range and modern control options - Existing open-vented systems and homeowners seeking a premium boiler

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Ideal Logic Max Heat - Compact boiler, filter included and ten-year warranty - Homeowners wanting a long warranty and straightforward cupboard installation

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Baxi 800 Heat - Ten-year warranty, magnetic filter and rear-flue option - Compact replacements and installations where flue flexibility matters

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Ideal Logic Heat - Outputs from 12kW to 30kW and compatibility with modern controls - Replacement programmes and a broad selection of normal domestic outputs

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Product ranges, guarantees and availability can change. The final selection should be confirmed against current manufacturer information and the installer’s written quotation.

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Worcester Bosch Greenstar Ri

 

The Greenstar Ri is a compact wall-mounted regular boiler.

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Current versions cover outputs from 12kW to 30kW, allowing the range to serve small, medium and larger homes. Worcester Bosch describes the boiler as small enough for installation within a standard kitchen cupboard.

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The Greenstar Ri may be considered where:

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• The existing boiler is a regular or heat-only model

• Cupboard installation is important

• Several outputs need to be compared

• The homeowner wants a widely supported UK boiler

• Solar-compatible stored hot water may be considered

• A longer guarantee is required

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Current Worcester Bosch information provides a seven-year standard guarantee, with up to ten years available on qualifying installations involving an accredited installer and appropriate system filter.

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Vaillant ecoTEC Plus Open-Vent Boiler

 

The Vaillant ecoTEC Plus includes an open-vent heat-only option intended for different property sizes and heating requirements.

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Vaillant describes the range as a flexible solution for homes using an open-vent arrangement.

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It may be considered where:

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• The existing property has an open-vented system

• The homeowner wants a higher-specification boiler

• Vaillant controls are being used

• Several heating outputs need to be considered

• The boiler is being installed with a separate cylinder

• The existing system arrangement is being retained

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The actual guarantee and controls package should be confirmed for the selected model and installer.

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Ideal Logic Max Heat

 

The Ideal Logic Max Heat is a compact heat-only boiler supplied with an Ideal system filter.

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It is available in outputs including 12kW, 15kW, 18kW, 24kW and 30kW and currently carries a ten-year warranty, subject to the manufacturer’s conditions.

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It may suit:

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• Cupboard installations

• Direct replacement of an existing heat-only boiler

• Smaller and larger domestic heating loads

• Homeowners seeking a ten-year warranty

• Systems requiring a separate cylinder

• Installations where a filter is to be included

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The heating professional should select the output using a heat-loss calculation rather than matching the rating of the old boiler automatically.

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Baxi 800 Heat

 

The Baxi 800 Heat is a compact heat-only boiler supplied with an Adey Micro2 magnetic system filter.

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Current manufacturer information includes:

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• Ten-year parts-and-labour warranty

• Magnetic filter supplied with the boiler

• Standard kitchen-cupboard fit

• Rear-flue option

• Compatibility with Baxi and Megaflo cylinders

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This boiler may be particularly relevant where:

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• A compact replacement is needed

• A rear flue would simplify the installation

• A ten-year warranty is important

• The homeowner wants the system filter included

• The property retains a separate hot-water cylinder

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The filter must be installed and maintained to retain the full Baxi 800 warranty. The boiler must also be registered, commissioned and serviced in accordance with Baxi’s current conditions.

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Ideal Logic Heat

 

The Ideal Logic Heat provides a more straightforward heat-only option with outputs from 12kW to 30kW.

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The range is compact, ErP compliant and compatible with Ideal’s Halo programmable controls.

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It may suit:

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• Straightforward replacement installations

• Rental and social-housing projects

• Homes retaining an existing cylinder

• Properties requiring a normal domestic output

• Installations where simple controls are preferred

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The exact warranty should be confirmed for the selected product and installation package.

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Choosing the Best Heat-Only Boiler

 

The best boiler is usually the model that:

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• Matches the calculated heat loss

• Works properly with the existing system

• Has accessible local servicing support

• Fits the available space

• Provides an appropriate guarantee

• Can be paired with suitable controls

• Has a practical flue route

• Can be commissioned to operate efficiently

• Is supported by a properly designed cylinder and heating system

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A premium boiler connected to dirty pipework, weak controls or an undersized cylinder will not necessarily outperform a more modest boiler installed as part of a well-designed system.

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Electric Heat-Only Boilers

 

An electric heat-only boiler heats water for radiators or wet underfloor heating without burning gas, oil or LPG.

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It may also work with a separate hot-water cylinder, but the boiler does not normally provide instantaneous domestic hot water.

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The EHC SlimJim is an example of an electric flow or heat-only boiler. Current single-phase models are available from approximately 4kW to 14.4kW.

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An electric heat-only boiler may suit:

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• Flats and apartments

• Small houses

• Properties without mains gas

• Annexes and extensions

• Homes already using wet radiators

• Properties where a flue cannot be installed

• Replacement of an older electric boiler

• Buildings with low calculated heat demand

• Installations using wet underfloor heating

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The EHC SlimJim can be used for radiator heating while a separate direct or indirect cylinder provides domestic hot water.

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Advantages of an Electric Heat-Only Boiler

 

Potential advantages include:

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• No gas supply

• No oil tank

• No combustion flue

• Compact boiler dimensions

• Quiet operation

• No combustion emissions at the property

• Compatibility with wet radiators

• Compatibility with underfloor heating

• Relatively simple appliance construction

• Flexible boiler positioning

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Electrical capacity and running cost remain essential considerations.

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A direct electric boiler uses electricity to produce heat at the property. It does not provide the same efficiency multiplier as a heat pump.

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For a larger normally occupied home, the installer should compare the electric boiler with an air-source or ground-source heat pump before the final decision is made.

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Electrical Requirements

 

An electric heat-only boiler normally requires a dedicated electrical circuit.

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Before selecting the output, a qualified electrician should inspect:

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• Main incoming fuse

• Available electrical capacity

• Consumer unit

• Meter tails

• Earthing and bonding

• Proposed cable route

• RCD or RCBO protection

• Electric showers

• Induction cooking

• Electric vehicle charging

• Immersion heaters

• Solar PV and battery equipment

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Single-phase electric boilers are commonly available up to approximately 14.4kW. Larger properties may require a three-phase supply or a different heating technology.

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The boiler output should not be chosen until the property heat loss and electrical capacity have both been assessed.

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Gas, Oil or Electric Heat-Only Boiler?

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Gas Heat-Only Boiler

Gas is normally the most straightforward option where:

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• Mains gas is available

• The property already has a gas heat-only boiler

• The existing cylinder and open-vented system are retained

• The flue position remains suitable

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Oil Heat-Only Boiler

An oil boiler may be appropriate where:

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• The property is off the gas grid

• An existing oil tank is available

• The home has a large heating requirement

• The property already uses an oil-fired conventional system

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The oil tank, fuel line, fire valve and flue must be assessed as part of the replacement.

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Electric Heat-Only Boiler

An electric model may be considered where:

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• Gas and oil are unavailable or undesirable

• Heat demand is relatively low

• A suitable electrical supply is available

• External equipment or a flue is difficult

• The property is a flat or small home

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The installer should compare expected fuel costs and electrical-upgrade requirements before recommending the final technology.

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Choosing the Correct Boiler Output

 

Heat-only boiler output is normally stated in kilowatts.

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The correct output should be based on the property’s calculated heat loss rather than the number of bedrooms or the rating of the old boiler.

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The assessment should consider:

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• Floor area

• Property age

• Wall construction

• Roof insulation

• Floor insulation

• Windows and glazing

• Air leakage

• Number and size of radiators

• Underfloor-heating zones

• Required room temperatures

• Hot-water cylinder recovery

• Planned extensions or loft conversions

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An oversized boiler may cycle on and off unnecessarily.

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An undersized boiler may struggle to heat the property and reheat the hot-water cylinder during cold weather.

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The cylinder-recovery requirement should be considered alongside the space-heating load, particularly in larger households.

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Choosing the Right Hot-Water Cylinder

 

The cylinder is central to the performance of a heat-only system.

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The installer should consider:

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• Number of occupants

• Number of bathrooms

• Bath sizes

• Shower flow rates

• Simultaneous hot-water use

• Cylinder recovery time

• Available cupboard space

• Water pressure

• Existing pipe sizes

• Immersion-heater requirements

• Solar thermal compatibility

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A cylinder that is too small may run out of hot water regularly.

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A cylinder that is unnecessarily large will occupy more space and store more heated water than the household requires.

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Older cylinders may also have limited insulation, slow recovery or internal corrosion. Boiler replacement provides an opportunity to assess whether the cylinder should be retained.

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Vented or Unvented Cylinder?

 

A vented cylinder is normally supplied from a cold-water storage cistern in the loft.

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Its hot-water pressure is influenced by the vertical distance between the storage cistern and the outlet.

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An unvented cylinder is supplied directly from the mains and can provide stronger hot-water pressure where the incoming supply is suitable.

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An unvented installation requires:

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• Adequate mains pressure and flow

• Expansion controls

• Temperature and pressure relief devices

• A compliant discharge route

• Installation by a suitably qualified person

• Regular inspection of safety components

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Converting to an unvented cylinder should follow water-pressure and flow testing. It is not automatically suitable for every property.

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Heat-Only Boiler Prices

 

Heat-only boiler prices vary according to the brand, output, controls, flue and complexity of the existing system.

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Current UK market guidance places a typical new boiler installation at approximately £2,500 to £4,000, with a broader installed range of around £1,700 to £6,000 or more. Conventional systems can cost more where cylinders, tanks, valves or extensive pipework are involved.

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For planning purposes:

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Heat-only boiler work - Indicative installed cost

Straight forward gas heat-only replacement - £2,200–£3,500

Premium heat-only replacement - £2,800–£4,500

Boiler and control upgrades -- £3,000–£5,000

Boiler and cylinder replacement - £4,000–£7,000+

Open-vented system converted to sealed - £3,500–£6,000+

Electric heat-only boiler replacement - £1,800–£3,500

Electric boiler with supply upgrade - £3,000–£6,000+

Oil heat-only boiler replacement - £3,500–£6,000+

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These figures are broad homeowner allowances rather than fixed APN quotations.

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What Affects Heat-Only Boiler Costs?

 

The final price may be affected by:

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• Gas, oil or electricity

• Boiler brand and model

• Required output

• Boiler location

• Flue type and route

• Existing system condition

• Cylinder condition

• Loft-tank replacement

• Pump replacement

• Motorised valves

• Expansion arrangements

• New heating controls

• Magnetic system filter

• System cleaning or flushing

• Chemical inhibitor

• Gas-pipe alterations

• Oil-tank or fuel-line work

• Electrical-supply upgrades

• Radiator replacement

• Heating zones

• Making good and decoration

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A low boiler-only price does not represent the complete installed cost.

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The quotation should identify every component included within the project.

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Replacing an Existing Heat-Only Boiler

 

A like-for-like replacement may involve installing a modern heat-only boiler in approximately the same location while retaining the cylinder, tanks and heating arrangement.

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The installer should inspect:

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• Existing boiler output

• Flue position

• Gas, oil or electrical supply

• Heating pump

• Motorised valves

• Hot-water cylinder

• Cold-water storage cistern

• Feed-and-expansion tank

• Radiators

• Pipework

• Heating controls

• System-water condition

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The existing system should not be assumed to be serviceable simply because it operated with the old boiler.

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Older systems may contain:

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• Sludge

• Corrosion

• Restricted pipes

• Damaged valves

• Poor insulation

• Inadequate controls

• Undersized radiators

• Leaking tanks

• An ageing cylinder

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These issues should be addressed as part of the installation quotation.

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Converting a Heat-Only Boiler to a Combi

 

Some homeowners want to remove the cylinder and loft tanks and install a combi boiler.

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This may release storage space, but the incoming water supply must be tested first.

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The work may require:

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• Removal of the old boiler

• Removal of the cylinder

• Removal or abandonment of loft tanks

• New hot and cold-water pipework

• Heating-pipe alterations

• Larger gas pipe

• New condensate route

• Flue alterations

• Electrical work

• New controls

• System cleaning

• Making good

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A combi conversion may not be the best solution where:

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• The home has several bathrooms

• Water pressure or flow is inadequate

• Several outlets are used together

• The existing pipework is fragile

• An immersion-heater backup is valued

• Future solar thermal installation is considered

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In those circumstances, retaining a heat-only arrangement or converting to a system boiler may be preferable.

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Converting From Heat Only to a System Boiler

 

A system-boiler conversion can allow the roof-space feed-and-expansion tank to be removed while retaining the hot-water cylinder.

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This may be suitable where the homeowner wants:

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• A sealed heating circuit

• Fewer external heating components

• Reduced loft equipment

• Stored hot water

• Continued support for several bathrooms

• A more modern system layout

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The radiators and pipework must be tested before pressurisation.

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Older systems that have operated at low open-vented pressure may reveal leaks after conversion to a sealed arrangement.

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Heating Controls

 

A modern heat-only boiler should be installed with effective heating and hot-water controls.

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Depending on the property, these could include:

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• Programmable room thermostat

• Smart thermostat

• Weather compensation

• Load compensation

• Cylinder thermostat

• Hot-water scheduling

• Thermostatic radiator valves

• Separate upstairs and downstairs zones

• Underfloor-heating controls

• Boiler interlock

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The controls should prevent the boiler operating when neither the heating nor hot water requires heat.

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Separate heating zones can be particularly useful in larger homes where different areas are occupied at different times.

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System Cleaning and Protection

 

A replacement boiler should not be connected to heavily contaminated system water.

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The installer should assess whether the system requires:

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• Chemical cleaning

• Power flushing where appropriate

• Manual radiator flushing

• Magnetic filter

• Chemical inhibitor

• Replacement feed-and-expansion tank

• New pump

• New motorised valves

• Radiator balancing

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The method should reflect the condition and construction of the system.

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Aggressive flushing may not be appropriate for fragile or badly corroded pipework.

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Qualified Installation and Certification

 

A gas heat-only boiler must be installed by a suitably qualified Gas Safe registered engineer.

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Oil-boiler work should be completed by a technician competent in oil-fired heating, commonly through an OFTEC-registered business.

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An electric heat-only boiler requires a competent heating installer and a suitably qualified electrician to assess and install the dedicated electrical supply.

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Following installation, the homeowner should normally receive:

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• Boiler commissioning documentation

• Building Regulations compliance certificate

• Manufacturer guarantee confirmation

• Electrical certification where applicable

• Heating-control instructions

• Service requirements

• Itemised invoice

• Cylinder documentation where relevant

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The manufacturer’s guarantee normally depends on correct registration, commissioning and annual servicing.

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What Should a Heat-Only Boiler Quote Include?

 

A complete quotation should identify:

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• Exact boiler manufacturer and model

• Boiler output

• Fuel type

• Boiler location

• Flue arrangement

• Existing cylinder condition

• Loft-tank condition

• Pump and valve work

• Heating controls

• Heating zones

• System cleaning

• Magnetic filter

• Chemical inhibitor

• Gas, oil or electrical-supply alterations

• Condensate drainage

• Removal of the old boiler

• Making good

• Guarantee period

• Commissioning

• Certification

• VAT

• Exclusions

• Possible additional costs

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This makes it easier to compare quotations on a like-for-like basis.

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A cheaper quotation may exclude controls, system cleaning, pump replacement, filters or work to the existing cylinder and tanks.

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Frequently Asked Questions

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What is a heat-only boiler?

A heat-only boiler heats water for radiators and a separate hot-water cylinder. It does not normally provide instantaneous domestic hot water.

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Is a heat-only boiler the same as a regular boiler?

Yes, in most homeowner and manufacturer literature, heat-only, regular and conventional boiler refer to the same general boiler type.

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Is a heat-only boiler always open vented?

Not necessarily. Traditional heat-only systems are usually open vented, but a heat-only boiler can sometimes be incorporated into a sealed system using separately installed components.

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Does a heat-only boiler need a cylinder?

Yes. A separate hot-water cylinder is normally required to provide domestic hot water.

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Does a heat-only boiler need loft tanks?

A traditional open-vented arrangement normally uses loft tanks. A sealed arrangement or unvented cylinder can remove some or all of these tanks, subject to system design.

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Which is the best heat-only boiler?

Leading options include the Worcester Bosch Greenstar Ri, Vaillant ecoTEC Plus Open Vent, Ideal Logic Max Heat and Baxi 800 Heat.

 

The best model depends on the required output, existing system, space, controls, guarantee and installer support.

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What size heat-only boiler do I need?

The output should be established through a heat-loss calculation covering the property construction, insulation, windows, radiators and cylinder-recovery requirement.

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Is a heat-only boiler suitable for a large house?

Yes. Heat-only boilers can be particularly suitable for larger homes using stored hot water and several bathrooms.

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Can a heat-only boiler supply two showers?

A correctly sized cylinder can supply several outlets, but performance depends on cylinder capacity, pipework and water pressure.

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Can I replace a heat-only boiler with a combi?

Often, but the incoming water pressure, water flow, gas supply and household hot-water demand must be assessed before removing the cylinder and tanks.

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What is an electric heat-only boiler?

An electric heat-only or flow boiler heats water for radiators or wet underfloor heating. Domestic hot water is normally provided by a separate cylinder.

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Does an electric heat-only boiler need three-phase power?

Smaller models can operate on a suitable single-phase supply. Larger heating outputs may require three-phase electricity or an alternative heating solution.

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Is an electric heat-only boiler expensive to run?

Running costs depend on heat demand, electricity tariffs, insulation and controls. Direct electric boilers generally consume more purchased electricity than a heat pump providing the same amount of heat.

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Does a heat-only boiler need annual servicing?

Gas and oil boilers should be serviced annually. Annual servicing is also commonly required to maintain the manufacturer’s guarantee.

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Who can install a heat-only boiler?

Gas boilers require a suitably qualified Gas Safe engineer. Oil installations require an appropriately qualified oil-heating technician. Electric-boiler circuits should be installed and certified by a competent electrician.

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Find the Right Heat-Only Boiler for Your Home

 

Choosing the right heat-only boiler starts with understanding the existing heating system, the condition of the hot-water cylinder and tanks, and the amount of heating and hot water the household requires. APN Boilers can connect you with experienced local heating professionals who can assess the property, calculate the required output, compare suitable gas, oil and electric heat-only boilers and provide a clear quotation for the complete installation.

 

Tell us about your property and existing heating arrangement to take the next step towards a reliable, properly designed and more controllable heating system.