Hot Water Cylinder News

Tank on Tank Heat Pump Cylinders Transforms Installations

McDonald Engineers’ ECOflow heat pump cylinder is available as a Tank On Tank system to reduce the space required and improve the installation process.


The tank on tank system is ideally suited for heat pumps which require a hot water cylinder and a buffer vessel.  Heat Pumps have experienced a steady growth in the UK, however the traditional approach is to have a hot water cylinder plus a separate buffer vessel.

McDonald Engineers Deliver Unvented Cylinder for Historic Castle

McDonald Engineers have shown their ability to deliver bespoke solutions for every type of application, by designing and manufacturing a 360 litre unvented POWERflow cylinder for a 16th century castle.


Invercauld Castle was originally built as the home of the Clan Farquharson however it now operates as a luxury shooting and fishing lodge in Aberdeenshire.

McDonald Engineers were recommended to the owners of Invercauld Castle when they chose to upgrade the direct vented system that supplied hot water throughout the castle.

McDonald Engineers Supply 36 Thermal Stores to the Military


McDonald Engineers has demonstrated its positions as one of the UK’s leading suppliers of thermal stores by securing an order for 36 of its THERMflows for an Army base in England.

The order was secured thanks to McDonald Engineers unique ability to manufacture solutions tailored to customers needs.  Each thermal store having all of the connections re-positioned to be on the front of the cylinder and a high efficiency system boiler coil fitted, to provide a rapid heat up.

CUBEflow Is the Answer for Housing Association

McDonald Engineers have demonstrated their position as the UK’s new market leader in rectangular hot water tanks with the supply of a 100 litre CUBEflow from stock.

The urgent enquiry came from a housing association in the North East of England who required an emergency replacement for an existing Elson rectangular tank to allow a vacant property to be refurbished and ready for a new tenant within the week.

Bespoke Rectangular Hot Water Tank

Bespoke Rectangular Hot Water Tank

McDonald Engineers have again displayed their ability to offer bespoke solutions to their clients' needs by adapting their CUBEflow rectangular hot water tank to deliver their first ever pentagonal tank.

The solution was developed to meet the requirements of a London housing association which approached McDonald Engineers to replace an existing rectangular hot water tank.

McDonald Engineers Respond to Hotel Emergency

McDonald Engineers has once again demonstrated its ability to respond to emergency enquiries by designing, manufacturing and delivering a complete hot water solution featuring two of their highly efficient 900 litre vented PLATEflow units in just 4 working days.

The issue arose when a busy city centre hotel experienced a burst hot water cylinder and called McDonald Engineers to assist.

Are You Specifying Your Solar Thermal Cylinders Correctly?

The lure of ‘free’ hot water, the potential to cut energy bills and the potential to earn money via the government’s Renewable Heat Incentive (RHI), is making solar thermal installations an increasingly attractive proposition.

And whilst our solar thermal cylinders have been successfully installed for decades, clients continue to have challenges when it comes to specifying cylinders to maximise the savings delivered by the project.

ECOflow Brochure

ECOflow Heat Pump Cylinders Used for Energy Savings Programme

 McDonald Engineers’ heat pump hot water cylinder, ECOflow, has been selected as the preferred solution for a Community Energy Savings Programme.

McDonald Engineers has already supplied a number of its ECOflow cylinders into the programme which is part of the government's Home Energy Saving Programme set up to encourage gas and electricity suppliers to deliver energy saving measures to domestic consumers in low income areas of Great Britain.

POWERflow Brochure

Social Housing Turns to Renewable Hot Water Cylinders

McDonald Engineers has supplied 12 of its Contract POWERflow unvented cylinders complete with heat pump and solar coils for the refurbishment of social housing in the west of Scotland.

The company’s Contract POWERflow can provide a cost effective alternative for larger projects requiring lower specification unvented cylinders.

And whilst the Contract POWERflow may be a more simplified unit than the original POWERflow, McDonald Engineers continue to offer a full customisation service to allow clients to include additional coils for use with multiple fuel sources.