What Glow-Worm does

Glow-Worm is a UK-based residential heating manufacturer and a brand/trading name of Vaillant Group UK Limited, founded in 1934 at the Derwent Foundry in Derbyshire and now headquartered at the Belper manufacturing plant. The company designs and produces gas central heating boilers across combi, system, and regular (open vent) configurations, all rated ErP 'A', and has expanded into low-carbon heating with the GeniaAir air source heat pump (5kW, 7kW, and 11kW), plus a cylinder and MiPro control range. Its smart controls stack — MiSet, MiGo Select, MiGo Link, and the Glow+ accessory line — uses the proprietary eBUS protocol to coordinate boilers and heat pumps, with MiGo Link providing app-based control and Apple HomeKit integration.

The business model is hardware-led (boilers, heat pumps, cylinders, controls) with a service revenue layer for repairs and annual servicing. Distribution is exclusively indirect: products are sold only through a network of Gas Safe registered installers who are members of the myREWARDS loyalty programme (shared with sister brand Vaillant), backed by a nationwide team of over 250 service engineers. Customers cannot purchase directly from Glow-worm; they locate installers via the 'Find an Installer' web tool. Pricing is not publicly disclosed, with quotes issued at the installer level; the manufacturer provides extended guarantee tiers of up to 10 years (when installed by myREWARDS members and paired with the Glow-worm Power System Filter), which functions as the primary commercial lever and reinforces installer loyalty.

Glow-Worm operates exclusively within the United Kingdom, has received 'Made In Britain' accreditation on its Energy, Ultimate, and Easicom boiler ranges, and holds an 'Excellent' Trustpilot rating. Its competitive positioning rests on a 90+ year manufacturing heritage, the depth of its certified installer network, and a controlled product ecosystem that couples boilers, heat pumps, and smart controls under a single communications standard.

Name

Glow-Worm

Legal name

Vaillant Group UK Limited

Website

https://glow-worm.co.uk

Company type

Private

Founded year

1934

Operating status

Operating

Headcount range

51–100 employees

Short description

Glow-Worm is a UK residential heating manufacturer (founded 1934, Belper, Derbyshire), owned by Vaillant Group UK Limited. It produces ErP A-rated gas boilers, the GeniaAir air source heat pump, and eBUS-enabled smart controls, sold exclusively via a certified myREWARDS installer network.

Ownership category

akta.pro rank

Product category

Residential Heating Equipment

NAICS

Heating Equipment (except Warm Air Furnaces) Manufacturing (333414)

SIC

Heating Equipment, Except Electric & Warm Air Furnaces (3433)

akta.pro primary industry

Boilers, Furnaces & Process Heating Equipment (IMAHAKAD)

akta.pro secondary industry

Heat Pumps (Air/Water/Ground Source) (IMAHAKAF)

Keywords

• Gas central heating boilers
• Air source heat pumps
• Smart heating controls
• Residential heating equipment
• Hot water cylinders

Headquarters

HQ city

Belper

HQ country

United Kingdom

HQ region

Europe

Offices1 record

Markets served

GTM type

B2B and B2C

Offering type

Hardware or Manufacturing

Cost components

Supply Chain, Operations, Personnel, Marketing or Sales, Technology or R&D, Infrastructure

Revenue model

1. Boiler Sales: Sale of gas central heating boilers including combi boilers, system boilers, and regular boilers to homeowners through installer network.
2. Heat Pump Sales: Sale of GeniaAir air source heat pump systems targeting both new and experienced heat pump installers.
3. Heating Controls and Accessories: Sales of smart controls (MiSet, MiGo Select, MiPro Sense), traditional thermostats, cylinders, and accessories.
4. Service and Repair: Nationwide team of service engineers provides repairs, annual servicing, and maintenance. Customers can book engineer visits online or through call centre.

Pricing tiers

Go-to-market motion1 record

Distribution channels1 record

Marketing channels4 records

Core offering

Glow-worm manufactures and supplies residential gas central heating boilers (combi, system, and regular), air source heat pumps (GeniaAir), hot water cylinders, and a range of smart and traditional heating controls. Products are sold exclusively through a certified installer network (myREWARDS) who handle installation, while Glow-worm provides direct nationwide service and repair through its own engineer team.

Product overview

Glow-worm is a UK-based heating manufacturer offering a comprehensive portfolio of heating solutions. The core product range includes combi boilers, system boilers, and regular (open vent) boilers, all with ErP A ratings. The company recently expanded into low carbon heating with the GeniaAir air source heat pump (available in 5kW, 7kW, and 11kW models), complemented by cylinder ranges and MiPro controls. Smart heating control is provided through the MiSet (wired/wireless touch interface), MiGo Select (wireless thermostat with weather compensation), and MiGo Link internet gateway (enabling app-based control and Apple HomeKit integration). Products are primarily sold through a network of certified Gas Safe installers with extended guarantee options for registered products.

Differentiator

Problem solved

Functional benefit

Products and services

• GeniaAir Air Source Heat Pump An air source heat pump system designed for simplicity and ease of installation, available in 5kW, 7kW, and 11kW output options, with single fan technology and flexible space function. Sold to installers and homeowners for low-carbon residential heating.
• Combi Boilers All-in-one combination boilers providing hot water and central heating for smaller households with low hot water demands (e.g. one shower or bath). Sold through certified installers.
• System Boilers Boilers fitted with a cylinder to provide steady hot water and a comfortable home temperature, suitable for properties with high water demand from multiple sources. Sold through certified installers.
• Regular (Open Vent) Boilers Heating and hot water boilers for larger households with multiple bathrooms and high hot water demand. Sold through certified installers.
• MiGo Link Internet Gateway Internet gateway device connecting Glow-worm boilers and the GeniaAir heat pump to the MiGo Link app and Apple HomeKit for remote access and weather compensation. Compatible with Glow-worm boilers from 2006 onwards.
• MiGo Select Smart Control Wireless room thermostat using eBUS technology to communicate directly with boilers for efficient energy use, with internet weather compensation when paired with the MiGo Link gateway.
• MiSet Heating Control Touch interface heating control with time programming assistant and boiler modulation for peak performance and optimum efficiency. Available in both wired and wireless models.
• Hot Water Cylinders Hot water storage cylinders complementary to the GeniaAir heat pump range and compatible with system boiler installations, providing stored hot water capacity.
• Boiler Service and Repair Nationwide team of over 250 service engineers providing boiler repairs, annual servicing, and maintenance. Customers can book engineer visits online or via the call centre.
• Heat Pump Service and Repair Servicing and repairs for the GeniaAir heat pump, delivered by Glow-worm's nationwide service engineer team, bookable online or via the call centre.

Quantifiable outcome

• Energy savings through ErP A-rated efficiency
• +1 more outcomes

Segments2 records

Ideal customer profiles2 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration1 record

Feature4 records

Partnerships

One partnership is on record.

• Vaillant GroupcoreStrategic or Co-development PartnerGlow-worm is a trading name, brand and registered trademark of Vaillant Group UK Limited. The company operates as part of the larger Vaillant Group, sharing resources, technology (including the myREWARDS loyalty scheme that covers both Glow-worm and Vaillant products), and distribution infrastructure.

Scale indicators4 records

Recent moves6 records

Expansion highlights5 records

Direct peers

• Viessmann: German heating manufacturer with a strong UK presence in boilers and heat pumps. Comparable premium product positioning, integrated controls offering, and direct competition in the UK low-carbon heating market where Glow-worm is now entering with GeniaAir.
• Worcester Bosch: One of the largest UK gas boiler manufacturers, also offering air source heat pumps and smart controls. Directly comparable product portfolio (combi/system/regular boilers, heat pumps, controls), UK-exclusive distribution through an installer network, and strong brand heritage comparable to Glow-worm.
• Vaillant: Parent group's primary UK-facing brand, offering boilers, heat pumps (aroTHERM), and smart controls. Glow-worm operates under Vaillant Group UK Limited and shares the myREWARDS/Club Energy loyalty scheme; the two brands are deliberately positioned at adjacent price/spec tiers, making Vaillant the most directly comparable UK peer.
• Baxi: UK-focused boiler manufacturer owned by BDR Thermea Group, offering combi, system, and regular boilers plus heat pumps. Closely comparable in target market (UK homeowners), product mix, installer-channel GTM, and parent-group structure (UK brand owned by European heating major).
• ATAG Heating: Dutch boiler manufacturer with a UK distributor network offering combi and system boilers. Comparable in product category and installer-channel distribution, with a similar premium positioning relative to Glow-worm in the UK market.
• Ideal Boilers: UK boiler and heating products manufacturer owned by Groupe Atlantic, offering combi, system, and regular boilers plus heat pumps. Comparable UK installer-channel distribution, similar product breadth, and parallel European parent-company ownership structure.
• Alpha Heating Innovation: UK boiler and heat pump manufacturer with a comparable combi/system/regular range plus installer-channel distribution. Smaller and more UK-focused than Glow-worm but operating in the same product category and serving similar homeowner and installer segments.
• Navien UK: Korean boiler manufacturer with UK operations, offering combi and system boilers plus commercial products. Comparable in product mix and installer-channel GTM, though less established in UK heat pumps than Glow-worm is becoming with GeniaAir.

Broad incumbents

• Daikin UK: Global HVAC and heat pump incumbent with a major UK presence. Not a direct boiler peer, but a primary competitor in the UK air source heat pump category where Glow-worm has launched GeniaAir, making it a comparable reference point for low-carbon heating competitive dynamics.
• Mitsubishi Electric UK: Established Japanese manufacturer of air source heat pumps and HVAC systems in the UK. A reference competitor for Glow-worm's GeniaAir heat pump entry, with substantially larger installed base and brand recognition in the UK low-carbon heating category.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks6 records

Key highlights7 records

Customer concentration

• Xx.com/glow_wormclub
• YouTubeyoutube.com/channel/UCAt0fc6Vkzan6EDCPl3ELNQ
• Facebookfacebook.com/about
• Instagraminstagram.com/glowworm_home
• LinkedInlinkedin.com/company/glowworm

Compliance1 record

Revenue estimate

Valuation estimate

Number of profiles

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Glow-Worm