General FAQs

The latest high efficiency boilers are more than 90% efficient, that is to say that about 90-93% of the fuel consumed when the boiler is firing is converted into heat. By comparison, an old conventional boiler can operate as low as 50% efficiency which means that 50p of every pound spent is going up the chimney.

Lightweight and compact, high performance collector panels are easily sited on pitched or flat roofs. Ideally they should be orientated south but they can operate with only a small loss of efficiency sited between 30 degrees east and 40 degrees west of south.

Boilers, just like fridges, washing machines, etc, are rated on their energy usage.

Condensing boilers are high-efficiency boilers that produce less carbon dioxide. They reduce the amount of heat that escapes via the flue, compared with normal boilers. Condensing boilers also convert 86% or more of the fuel they use into heat and many carry the 'Energy Efficiency Recommended'

Part L of the building regulations sets out standards to help in the conservation of fuel and power and as such directs the type of appliance installed, heating system controls, zone controls and boiler interlocks in addition to the construction of properties.

For more information: Contact the Communities and Local Government website (formerly the Office of the Deputy Prime Minister or ODPM) www.communities.gov.uk

We thoroughly recommend the good practice of cleansing a system as an important part of the installation process. Where possible, it is best practice to cleanse an existing system prior to installation of the new appliance After installation the system should be cleansed of debris and refilled with inhibitor.

The recommendations within BS7593 should be followed, whilst also paying attention to notes within an appliances Installation & Servicing instructions and those instructions as directed by the flushing agent manufacturer.

When a traditional boiler and cylinder is replaced with a combi boiler, any existing shower should be examined for suitability. This might have been a pump assisted power shower, for example, designed for low-pressure systems. Combi boilers by contrast produce hot water at mains pressure, which means they are compatible to either a mains pressure balanced or thermostatically controlled shower.

Water softeners are now commonly used, especially in hard water areas around the UK. With a condensing boiler, if you intend to use a softener unit you must remember that due to the change in ph level (i.e. the water being more acidic), it would be unwise to fill your central heating system with such water. This will implicate the longevity of your central heating system and pipe work. Therefore it is wise, when adding water using the filling loop to your boiler and that this is taken prior to the softener unit.

The technology inside a heat pump works on similar principles to those of a domestic fridge. Heat pumps take advantage of the principles of thermodynamics in order to achieve their results. A water and glycol mixture is pumped around the collector circuit and causes the refrigerant in the evaporator to turn into a gas. This refrigerant passes through the compressor, causing the temperature to rise significantly. The hot gas moves to the condenser, where it condenses and the latent energy is released into the heating circuit.

When properly installed, an air source heat pump can produce up to five times more heat energy to the home than the electrical energy it consumes.

The basis of heat pump efficiency is known as ‘Coefficient of Performance’ (or ‘COP’). For example, 3 units of environmental energy plus 1 unit of electricity equals 4 units of heating energy, hence a COP rating of up to 4. This is subject to suitable low flow temperatures and house insulation levels.

Both types of air source heat pumps, air-to-air and air-to-water, operate in a similar way. An external fan unit draws in the outside air and converts the latent heat it contains, even on the coldest of days, into warm air or hot water, depending on the type of heat pump.

A Greensource air-to-air heat pump can cool a property as well as heating it. It also has the added advantage of acting as an air purifier and dehumidifier.

In the majority of circumstances the answer is no. The Worcester system is all you need to satisfy your total heating and hot water requirements. However, we will be pleased to advise on your individual situation.

Ideally, for maximum benefit and efficiency, a heat pump is best used with under-floor heating, but oversized radiators are also an option.

The VAT on solar systems varies depending on who is installing it. DIY solar systems carry 15% VAT. A system installed by a professional installer carries 5% VAT.