Technical Support for Oil Boilers

Yes, we do recommend the use of suitable water treatment in the form of an inhibitor to the heating water system, in accordance with the water treatment manufacturer's instructions. The concentration level of the water inhibitor should be checked every 12 months or sooner if system content is lost.

Seasonal Efficiency is the average annual efficiency achieved in typical domestic situations, and is confirmed by independent testing bodies. These figures are verified on www.ncm-pcdb.org.uk. A simplified explanation of Seasonal Efficiency is that this is the average efficiency of the boiler over a year, taking into account climate, housing conditions, occupancy patterns, and controls. Combustion Efficiency is defined as the amount of heat released during combustion over the heating value of the fuel burned. This is usually shown as the net efficiency on a digital flue gas analyser, and may be higher or lower than the Seasonal Efficiency, depending on the time of year and the heat load.

Regarding an “app” or WiFi controlled systems. As with most of these systems we advise to contact the manufacturer to ascertain whether the “base station” can generate a 240v signal. Our boilers require this signal, from the room ‘stat via a zone valve, in order to energise. If your unit can produce this signal voltage then, in theory, the boiler should function.

If the system has an “open therm” configuration then this is only for modulating boilers, Grant boilers are range-rated and do not modulate. If the configuration can be changed to an “on/off” format then this, again in theory, should work

As in the summer season, when heating is not required, simply switch your controller’s heating demand regulator to the “off” position so the boiler will only energise for DHW demand.

With Grant external units, a frost thermostat is already factory fitted to protect the boiler.

However, should you install an internal boiler in a remote setting i.e. a garage etc, then a frost ‘stat MUST be fitted. In both cases a boiler return ‘stat would be a good idea to install. This controls the return water temperature and turns off the boiler earlier than the normal ‘stats which sense air temperature. This will reduce oil wastage and energy.

Part L of the Building Regulations sets out standards to help in the conservation of fuel and power and as such, it directs the type of appliance installed as well as heating system controls, zone controls and boiler interlocks in addition to the construction of properties. Heating engineers and installers installing new heating systems should be familiar with the requirements of Part L. 

Read More

No, condensing oil boilers can only run on kerosene.

Copies of the latest Installation Instructions and Technical Guides for Grant UK’s current Vortex oil boiler ranges can be downloaded from our website here. If you require the manual for an older model of boiler, please download the TechBox app where all of Grant’s current and archives product manuals are available to view.

Oil boilers are not being banned however, from 2025 new build properties could be required to have low carbon heating, such as a heat pump, so they can meet the proposed Future Homes Standard. The Future Homes Standard is a set of standards that will complement the Building Regulations to ensure new homes built from 2025 will produce 75-80% less carbon emissions than homes delivered under current regulations.

The award winning Vortex boiler was launched in 2002. In the subsequent years that followed there was a customer demand for a competitively priced ‘A’ rated boiler, so the R&D Team at Grant devised the Eco range to meet this growing demand. The Vortex Pro has a larger heat exchanger area and more case insulation which gives it a slightly higher efficiency than the equivalent Eco model output.

Yes, although we recommend the return temperature remains above 40°C. However, it is more usual to connect underfloor heating via a system of mixing valves or even a separate calorifier so that radiators which are normally heated to a higher temperature can be served as well. In order for the boiler to remain under guarantee, we stipulate it must be serviced every twelve months. Any work undertaken must be carried out by a competent service engineer.

On both the Pro and Eco range the secondary heat exchangers are made of stainless steel and the turbulators are made of 1.5mm aluminium however depending on the output and model of the boiler, the amount and the length of turbulators differ. For further information, please refer to the manual or contact technical directly on 01380 736920

All Grant Vortex floor standing oil boilers are biofuel compatible (depending on type of biofuel and % blend, for example: HVO or FAME). Biofuels are a renewable energy source, created from organic matter or waste. It will likely play an important role in reducing carbon dioxide emissions in the future. As biofuels emit less carbon dioxide than conventional fuels they can be blended with existing fuels, or used as 100% sustainable fuels, as an effective way of lowering carbon emissions.

Read More

Yes. Effective from 15th June 2022, if you are installing a new gas or oil boiler, you will be required to carry out a full room by room heat loss calculation before completing the installation. The aim of this process is to encourage correctly sized heating systems to be installed as the Part L Building Regulations state that systems should not be significantly oversized.

Read More

Yes, providing the system is cleansed thoroughly and updated to fully pumped operation (not gravity hot water).

A Grant Boiler cannot be installed directly onto a one pipe system as the return water temperature will be too low, this will cause internal condensing which will corrode the primary heat-exchanger. This return water must be above 40°C

The only way to establish a boiler into this type of system is by installing a plate heat-exchanger between boiler and pipework or supplying the circuit through a low-loss header arrangement.

This ensures the boilers are separated and will have “back-end” protection and, more importantly, the installation will be covered by the guarantee.

It is mandatory to power flush a system in order to fulfil Grant UK's guarantee.

However, if the system is old a power flush may cause undue pressure on the aging pipework, radiators valves etc. In these cases, the circuits should be chemically cleaned to assure the components are free of debris and system scale etc. and will not affect the new boiler.