With the increased popularity of unvented cylinders and mains fed appliances it is essential to establish the performance of the main supply.

Many installers carry out pressure tests, but overlook a flow test, which can result in unvented cylinders not performing to expectations, leaving houses with only a trickle of water to supply expensive power showers and designer taps.

So when it came to renovating a sizable semi-detached house, brimming with modern fittings, Proprietor of CN Plumbing, Colin Page, fitted GAH's Dualstream.

The system combines the benefits of stainless steel unvented cylinders with a second vessel - the accumulator, which increases volume.