Today we’re near Tunbridge Wells, Kent, to look at Fordcombe Primary Church of England School.

A typical nice British village school on a windy cold day

Our brief was to get the heating working properly in the main building.  Our customer had experienced ongoing problems over the past few years with radiators not heating up properly – or at all – and were having to rely on numerous electric heaters to supplant the failing system.  In the main classroom, half the radiators didn’t work.  Efforts from their maintainer had amounted to little or no improvement, and involved changing the thermostat and a few other misguided remedies.

Old boiler. Most of the case screws were missing, which tells a story.

The customer had obtained two quotes to replace the boiler and fix the heating, one was from British Gas, the other from a local contractor.  In both cases they had advised that the problems were down to the boiler being undersized in output, and they recommended a larger unit would resolve the problem.  One of the contractors (BG) had advised that the large gas main from the commercial meter would also need upgrading to support the larger boiler.

The school got a third opinion from us, following a recommendation.

Keeping an open mind, a simple basic heat calculation showed that the existing Ideal boiler was plenty large enough, but the problems lay more down to the pipework design and consequent air entrapment.  We also advised that two different controlled zones would be useful, as there was a large hall used for drama, lunch and PE and this had different heating characteristics (fan convector heaters) and operational needs, distinct from the classroom areas.

Hall and convector heaters; now on separate controls

We fitted a new Worcester boiler (with an 8yr warranty), split the pipework into two zones, and provided air vents to help prevent air entrapment in certain areas of pipe inside a false ceiling.

Worcester Bosch CDi boiler. We’ve added an additional German Reflex expansion vessel (to give the internal boiler vessel reduced stress) and zoning controls, plus a Worcester system filter.   And a hoover, by the look of it.

Apparently the building has never been as warm and the teachers leave their cardigans on the peg.  The new boiler has a slightly lower output than the outgoing one……so the money saved on the erroneously recommended larger boiler and gas pipe can now be spent somewhere more deserving.