Testing the water

 18 Aug 2015

Zip InLine CEX and Spectrum Housing Group

Spectrum Housing Group, a non-profit organisation, formed in 2007, own and manage approximately 18,000 homes and maintain a further 45,000 across the South of England through Spectrum Property Care. They work in partnership with local authorities, health trusts, statutory bodies, a range of voluntary organisations and higher education establishments to create safe, sustainable communities.

One of their buildings, Norfolk House, Reading, was experiencing problems with instantaneous water heaters, installed in their 51 studios, to provide hot water for showering and the wash hand basin. The existing products were costly to run and prone to failure.

Barbara Wojna, the Accommodation Manager for Spectrum Housing Group, decided that they needed an alternative to measure against the current product. Consequently a trial was established where the Zip InLine CEX was installed to provide one studio and the other product installed in the same location but servicing another identical one. Both water heaters were monitored to record the amount of energy used to supply the units. Other electrical items such as cookers etc. were not included in the analysis.


Barbara said, “I had selected two studios with similar occupancy, 2 residents, but we didn’t advise them about the tests, so that they continued to use the shower and basin as they had done before, thus not affecting the trials.

We examined the usage and found that the Zip CEX had used far less than the other heater, which was very reassuring.

However, what really surprised us was that the maintenance officer had made an error at set-up and installed the Zip heaters into a studio occupied by two residents, whereas the other product was only supplying hot water to one user.

We ensured that the mains water feed to both heaters was the same, eliminating any possibility that the incoming water temperatures were different.“

“We kept the trial running for three months and the Zip heater was always found to be using less power”.

“As the Zip product was slightly more expensive I needed to be sure that we were making the correct decision before we purchased the Zip InLine CEX for all of the replacements required”.

“The tests were conducted in 2012 and, to date, we have had no problems — we always use Zip heaters now for our replacement programme”.

Zip InLine instantaneous water heaters with their electronic controls and bare-wire technology are the most energy efficient way of directly heating water electrically.