Glossary of terms

An app is a software application that is downloaded by a user to a mobile device.

Benchmark is an industry recognised scheme which exists to promote the highest level of installation, commissioning, and servicing of heating and hot water systems. This is completed at the end of the installation and can be found at the back of the manufacturer’s instruction manual

Boiler Plus is government legislation which ensures that homes in the UK have efficient heating systems. Since April 2018, all new boiler installations require a minimum ErP efficiency of 92% and have time and temperature controls fitted.

Club Energy is our loyalty scheme for our Glow-worm installers who receive a whole host of dedicated services, technical and support teams as well as business advice.

A combination or ‘combi’ boiler provides central heating and hot water from one compact appliance without using a separate hot water storage tank. Water is taken directly from the mains supply to offer heating and hot water almost immediately when it’s needed.

A condensate pipe is a white overflow pipe that allows your boiler to dispose of condensation to an outside drain via this pipe.

A control (or thermostat) allows you to easily regulate the temperate of your home as well as managing your hot water demands using a simple analogue heating timers or through a smart device.

The diverter valve is a part inside the boiler that switches the flow of water between hot water at your taps and your central heating.

Products that use energy, such as boilers are rated according to the energy they consume. The ratings usually range from A+++ to G, depending on the product.

The rate at which water comes out of the taps or shower. A poor flow rate means that water coming out of your taps or shower will be low.

A flow switch is a major part in a combi boiler as it senses when you turn on a hot water tap and the boiler.

All boilers produce gasses that need to be emitted outside of your home. The pipework for this is known as a flue.

The Gas Safety Register is the official list of gas engineers who are qualified to carry out work safely and legally on gas appliances.

A heat exchanger is inside a boiler to transfer heat from the gas burner to the water in the system/radiators. They are also used in a combi boiler to heat the hot water for your hot taps and showers.

MiGo from Glow-worm is your personal heating assistant. MiGo speaks the same language as your boiler to ensure you’re only using the required amount of energy helping you to save money on your bills.

A pilot light is a small constant gas flame that ignites your boiler when heat or hot water is required. They are usually found in older boiler models.

PRV is a safety device build into a boiler that activates if the water pressure rises to a level the boiler cannot cope with.

‘Bleeding’ is a term used for letting air out of your radiator and heating system by opening the small valve at the top of the radiator to allow trapped air to escape.

Open vent or ‘regular boilers’ work as a heating system only. They’re able to keep your home warm through a central heating system and provide hot water through a hot water storage cylinder. Regular heating systems require a cylinder which is often kept in an airing cupboard and a cold-water tank usually in the loft.

Smart heating offers an advanced way to control the temperature of your home. Instead of using a standard thermostat, this type of system combines intelligent sensors and user-controlled apps to ensure a comfortable, efficiently heated home throughout the year.

A system boiler powers your central heating directly and also provides hot water that’s kept in a separate storage cylinder. These compact appliances are capable of heating a home whilst producing enough hot water to supply several showers and taps at the same time.

A thermostat (or control) is a device that works to maintain a constant temperature in your home by measuring the ambient temperature and comparing it to the programmed settings. It will then switch the boiler on or off as required to reach the correct temperature.

Time switches turn the boiler on or off at the time you set it to.

Is an adjustable valve connected to each radiator that allows you to change the temperature in each room by regulating the flow of hot water to each individual radiator.

Combi and system boilers need a minimum pressure within the system to work. If the pressure drops below a certain level, the system will not fire.

Weather compensation helps your heating to operate efficiently by monitoring both internal and external temperatures and adjusting the boiler settings accordingly.

The ability to modulate the flow temperature from your boiler based on the room temperature to help you get the ideal temperature in your home. This requires the control and boiler to 'speak' the same language. Glow-worm appliances use eBUS.