Sunday, June 23, 2024

The biggest problem with water heating? You don’t know which problems you have!

Adrian Barber suggests ways to maximise water heating efficiency.

Many student accommodation properties have multiple local hot water cylinders supplying groups or ‘clusters’ of rooms.

Cylinders are generally plumbed in, locked in a dark tank cupboard, and only see the light of day following ‘lack of hot water’ complaints.

Water cylinders engender many and varied issues. But identifying these problems, then locating and fixing them is time consuming and costly for maintenance teams. Older systems become a game of ‘whack-a-mole’ – one issue is resolved, others spring up. Problems cost time and money and disrupt room occupants!

The biggest problem with water heating, is that you don’t know which problems you have, or where they are.

With space heating in student dwellings, managers appreciate that monitoring and controlling at point-of-use is most effective in managing consumption. The more data, the better the management strategies. Even minimal savings per room become significant when multiplied by 500 occupants. When data capture is applied to water heating there are many other advantages too.

Problem solving

Most issues occur because it is simply not known what is happening in the system e.g. Volume of water entering; Water temperature within the tank; Leak/wastage; Flowrates through pipes; and tap temperature. Gathering this information requires several monitoring points with sensors and meters collecting data.

The new generation of ‘smart’ tank has such capabilities. Pre-plumbed and pre-wired with factory-fitted on-board controls ensures a consistency of production quality, and a familiarity of installations across a site. Fitting time, and costs are cut, and maintenance is more efficient.

When connected to a centrally controlled system, data is transmitted to a hub where Energy, Maintenance, and H&S Teams can see precisely what is happening throughout their system. In addition, unusual usage patterns, leaks/wastage, and faulty components are reported.


Three levels can be identified for Water heating efficiency-analysis.

  1. Replacement: Cylinders are generally considered to be ‘a fit-it and forget-it’ product. Many are simply past their best and need changing. Greater efficiency will be immediate from a new cylinder, whatever its monitoring capabilities.
  2. Pro-active analyses: Accurate and intense monitoring of both energy and water consumption accumulates data as never before. From this, heating strategies are better defined. This results in stricter temperature control, and greater maintenance efficiencies.
  3. Nuances: An example is a pipe sensor. A small device that pinpoints invisible yet significant wastage. it detects water flow, and temperature at point-of-use. Dripping taps or faulty toilet cisterns are no longer imperceptible. Maintenance Teams are alerted. The swifter their action, the lesser the amount of water wasted.


Water safety is a subject where greater understanding of events and logging data is critical. What is the water temperature: In the tank? -When it leaves the tank? -At the outlet? Is Legionella a risk? Are Water Safety Plans adhered to? Can this be evidenced? Are taps and showers presenting scolding hazards?

These questions are answered when a water system is monitored absolutely.

Customer relations

The quality of student accommodation has soared in recent years, delivering superb facilities and outstanding comfort. Rental values are commensurate. But with this, increased resident expectations.

Unreliable water supply is unacceptable. As are frequent knocks on doors from maintenance teams hunting for problems. Remote monitoring reveal’s accurate location of faults, speeds up repair, and encourages scheduled maintenance regimes. All of which reduces interaction with, and interruption of, occupiers.

If a problem is known, it can be dealt with. But currently, those responsible for water heating efficiency, like their cylinders, are in the dark!

This article appeared in the May 2024 issue of Energy Manager magazine. Subscribe here.

Further Articles