Grant Heating Controls

Grant UK's heating controls are the Aerona Smart Controller and the Aerona Remote Controller, both built for the company's own air source heat pumps rather than for the wider boiler market¹. The Smart Controller manages three heating zones plus domestic hot water, and the Remote Controller gives access to the heat pump's core parameters to set, view and adjust, with an LCD screen showing operating status symbols and icons¹. Grant's Aerona 290 heat pumps run from 4kW up to 15.5kW heating outputs, and the Smart Controller is designed for installation with both the Aerona³ and Aerona 290 ranges².

The practical point for a household is ownership. These are physical controllers on the wall and at the heat pump, not a subscription service, and the documented functions are local: scheduling, zone control and parameter access. What they do not do is remove the household's dependence on the electricity grid that runs the heat pump, or on the installer who commissioned the system. Grant UK's own route to that installer is an online search tool on its website¹.

Underfloor heating is the other half of the picture. Grant's Uflex system uses a manifold that controls the distribution of water from the heating source throughout the underfloor circuits, with balance set by adjusting the flow meters³. A zone is an area or a room controlled independently via a room thermostat, so zoning is a controls question as much as a plumbing one³.

What Grant heating controls cover: the range at a glance

Grant's control range is narrow and specific. There are two controller options for the heat pumps, the Aerona Smart Controller and the Aerona Remote Controller, and the Smart Controller is the one that handles zoning and scheduling, with three heating zones plus domestic hot water¹. The Remote Controller is the service and commissioning side of the same system: it provides installers and end-users with access to the heat pumps' core parameters to set, view and adjust, and its LCD display screen shows operating status symbols and icons¹.

That split matters when a household is deciding what it is buying. The Smart Controller is the everyday interface, and Grant describes setting up heating schedules with ease as one of its functions². The Remote Controller is closer to a technician's panel that a competent householder can also read. Neither is a general-purpose smart thermostat that will drive a third-party gas boiler.

The underfloor side is controlled differently again. Grant's Uflex underfloor heating system is a screeded system using 16mm pipework, and in the documented installation it was laid throughout the entrance hall, dining room, kitchen, living room, office and utility room of a property¹. Control there runs through the manifold and room thermostats rather than through the heat pump controller alone.

Grant UK: the company behind the controls

Grant UK is a renewables and heating manufacturer whose UK presence is built around heat pumps, underfloor heating and oil boilers. Its air source heat pump range is the Aerona line, and the Aerona 290 is described as an air to water heat pump built for the next generation⁵. The company publishes its own product support material, including installation instructions and brochures for the Uflex underfloor range and for the Aerona heat pumps³.

The controls sit inside that product ecosystem rather than being sold as a standalone controls brand. That is the central fact for anyone comparing Grant with a dedicated thermostat maker: the Aerona Smart Controller is designed for installation with Grant's own heat pumps, and the documented compatibility is with the Aerona³ and Aerona 290 ranges¹. A householder with a Grant heat pump gets an integrated control package. A householder with a different maker's boiler is not the target market.

Grant also supplies components that reach into oil heating. The Control Box 535 is a Riello control box used in some Grant oil boilers⁶. That is a burner control rather than a room controller, and it is worth being clear about the distinction: it manages combustion equipment, not the household's heating schedule.

On the grant side of the name, the word "grant" in this field also means public funding, and the two should not be confused. Grant-awarding bodies include local authorities, utility companies such as electricity suppliers, and agencies like the Energy Saving Trust, and a grant is money paid directly by those bodies to installers to fund work done for someone else⁷. That definition sits behind every scheme discussed later on this page.

Controls within a whole-house system: boiler, cylinder and underfloor heating

A Grant control system is best understood as one layer of a whole-house installation. In a documented Grant installation at a self-build home in Cornwall, an Aerona 290 heat pump, a hot water cylinder, a solar thermal system and underfloor heating were installed together². The controls have to coordinate all of that: the heat pump's output, the cylinder's hot water demand, and the underfloor circuits.

The manifold is where the underfloor side is managed. Grant states that it controls the distribution of the water from the heating system's source, whether that is a boiler or a heat pump, throughout the underfloor system³. Balance between circuits is achieved by adjusting the flow meters so that the flow rates supplied to each zone are at the optimum level, and Grant states this should be carried out by a heating engineer³.

Setback control is the other documented function worth knowing about. Grant describes its purpose as avoiding the wasteful use of energy to continually reheat the floor from cold³. That is a controls behaviour rather than a hardware feature: the floor slab holds heat, so letting it cool completely and then driving it back up costs more than holding it nearer temperature.

There is a policy argument that sits alongside this. Written evidence to a parliamentary committee argued that the scope of heating measures should be wider to better support consumer needs and include other key components such as hot water storage cylinders⁸. In other words, a controls package that ignores the cylinder is only part of a system. Grant's own documented installations pair the heat pump with a cylinder, which is consistent with that view.

Underfloor heating controls: the Uflex manifold, pump and mixing set

The Uflex range is Grant's wet underfloor heating system, and its controls are mechanical and hydraulic as much as electronic. The manifold distributes water from the heat source across the underfloor circuits, and the pump and mixing set blends the flow temperature down to what a floor can safely take³. Grant documents setting the thermostatic mixing valve to setting 3³.

Zoning is defined clearly by the maker: a zone is an area or a room that is controlled independently via a room thermostat³. That definition answers a common question directly. If a household wants the kitchen and the living room to run at different times or different temperatures, those are two zones and they need two room thermostats. The manifold alone does not create that separation.

Grant's documentation for the Uflex range is dated and versioned, which is useful for anyone checking they have the current instructions. The Grant Uflex Manifold and the Grant Uflex Pump and Mixing Set instructions are each revision 1.0 and dated August 2025, the Grant Uflex UFH Installation and Operating Instruction is revision 1.0 dated February 2026, and the Grant Uflex Underfloor Heating Range Brochure is dated April 2026³.

For a household, the independence question here is modest but real. A wet underfloor system with a manifold, pump and mixing set is locally controlled hardware. It does not need a cloud account to run. What it does need is a heating engineer to balance it properly, and a heat source, which in a Grant installation is likely to be the company's own heat pump.

Compatibility with the Aerona 290 heat pump range

The Aerona 290 is Grant's current air to water heat pump, available in heating outputs from 4kW up to 15.5kW². It holds Quiet Mark accreditation through the range, which is an independent noise certification rather than a maker's claim⁵. The Aerona Smart Controller is designed for installation with both the Aerona³ and Aerona 290 heat pumps¹.

Grant describes the controller's compatibility in two places. One Grant page states it is designed for installation with both the Aerona³ and Aerona 290 heat pumps, while a Grant support article describes it as compatible with both the Aerona³ and Aerona 290 heat pumps¹. The two statements point the same way, and the compatibility is within Grant's own heat pump families.

Grant publishes revision 1.9 of the Aerona 290 Air Source Heat Pump installation instructions, dated August 2026². That is the document an installer works from, and it is the one that governs how the controller is wired and commissioned.

Documentation and instructions: what to download before you install

Grant publishes its technical documentation through product support pages rather than a single downloads hub. The underfloor heating support page lists the Uflex manifold and pump and mixing set instructions, the UFH installation and operating instruction, and the range brochure, each with a revision number and a date³. The air source heat pump support page carries the Aerona 290 installation instructions at revision 1.9, dated August 2026².

Getting the current revision matters because these documents change. The pattern across the range is that instructions are versioned and reissued, and an installer working from an older revision may be following superseded guidance.

There is a wider regulatory direction of travel on handover documentation. Approved Document L Volume 1: Dwellings was updated to clarify requirements relating to the provision of maintenance and operation information to owners of dwellings with mechanical ventilation, and to make clear that Home User Guides should be provided⁹. That is about new-build compliance rather than retrofit controls, but it reflects the same principle: the household should end up with the paperwork.

Where a grant is involved, the paperwork has a hard deadline attached. Under the Green Homes Wales terms, a borrower must apply for and have received an Installation Grant Letter before any work starts on installing the eligible measure covered by it¹⁰. The Welsh-language version of the same terms states the same requirement¹¹. That is a condition on the household, not on the installer.

How controls fit with the Boiler Upgrade Scheme grant

The Boiler Upgrade Scheme provides upfront capital grants towards the cost of installing approved heat pumps and, in limited circumstances, biomass boilers¹². The published grant value is £5,000⁴. The scheme is installer-led: the installer applies for the grant on the property owner's behalf, discounts it from the invoice, applies to Ofgem for a grant voucher, and redeems the voucher after installation and commissioning⁴.

The application is installer-led, with the installer applying for the grant on the property owner's behalf¹³. The grant is applied upfront as a discount to the cost of the installation, and the householder does not receive the grant directly, because it is paid to the installer¹⁴. In practice the installer discounts the grant from the invoice, applies to Ofgem for a grant voucher, and redeems the voucher after installation and commissioning¹³.

Eligible technology under the scheme includes ground source heat pumps¹⁵. The scheme is described in official statistics as providing upfront capital grants to support the installation of heat pumps and biomass boilers in homes and non-domestic buildings¹⁶, and separately as contributing upfront capital grants to support the installations of low carbon technologies¹⁷. The UK Government's Boiler Upgrade Scheme provides grants to assist with installation costs¹⁸.

Where controls fit is straightforward: a heat pump installation needs controls to run, and the grant covers the installation rather than a separate controls purchase. Guidance for property owners was updated in version 5.1 with updated guidance relating to the uplifted grant value¹⁹, and a later summary places greater emphasis on installers' obligations to manage application accuracy, apply the grant discount upfront, and provide clear information where requested²⁰. Installer guidance carries the same emphasis²².

What owning Grant controls means for household energy independence

Grant controls are locally owned hardware, and that is their main independence virtue. The Smart Controller and Remote Controller are physical devices on the property, the underfloor manifold and pump set are mechanical, and none of the documented functions require a subscription. A household that buys a Grant heat pump and controls package owns the equipment outright.

The dependence that remains is substantial and worth stating plainly. A Grant heat pump runs on electricity from the grid, supplied by an electricity supplier, so the household's heating is only as independent as its electricity supply. The controls do not change that. The system also depends on the installer who commissioned it: Grant's documented route to a local installer is an online search tool on its website¹, and the underfloor balancing that keeps the system efficient should be carried out by a heating engineer³.

There is also a grant-related dependence where public funding is used. Under the Green Homes Wales terms, the award of an Installation Grant Offer Letter is discretionary, with no guarantee that any particular amounts of Installation Grant will be available for any particular period¹⁰. The same terms state that before installation works start, a change of installer or eligible measure requires contact with the Development Bank of Wales and re-validation, with no guarantee of approval, particularly if it would result in additional Installation Grant being payable¹⁰. A household that has accepted a grant letter has less freedom to change its mind than one that has not.

For context on how grants vary across the UK, the picture is fragmented. Grants for home energy efficiency in Belfast are available to homeowners and private tenants²³. The Warm Homes: Local Grant in Greater Manchester covers owner occupied properties with an EPC rating of Band D, E, F or G²⁴, and the London Warmer Homes programme requires the home to be privately owned, either by the householder or their landlord²⁵. Tameside's Your Home, Better service does not offer grants or funding, but can identify sources that could help towards the costs of home energy projects²⁶. Scotland's Green Heat Finance Taskforce work and the Welsh Ynni Cymru grant sit alongside these²⁷.

The controls themselves are the part a household keeps. The grid connection, the installer relationship and, where used, the grant conditions are the parts it does not.