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Water Heat Pump

Mr West in North Devon

Client: Mr West

Equipment: Domestic Air to Water Heat Pump

Fault: Hot Water Issues

HPSL were approached to investigate problems with a Grant Aerona Air to Water heat pump installed in a holiday cottage on the North Devon coast.   The property also had a solar thermal hot water installation which provided additional heat to the cylinder.


Following a visit to replace faulty parts, the system developed a problem where, despite being set to 45 degrees centigrade, the hot water would only reach 35 degrees and then drop down to around 25 very quickly.  During a thorough check of the system operation we were able to trace the fault to one of the controllers.  Field Settings on this controller were not being retained after it had powered off; this was causing the flow temperature set points to be reduced and the circulation pump being set to run continuously.  These settings were causing the system to strip heat from the cylinder.


After intensive investigation, and with constant communication with Grant UK Technical Helpdesk, the cause of the issue was found to be a faulty printed circuit board on the outdoor condensing unit combined with a temperature sensor that was reading 25 degrees above the actual temperature.  After replacing both of these parts the system was returned to its normal operation and has been stable ever since.




Torridge District Council

Equipment: Commercial Biomass Boiler & Underfloor Heating

Fault: Pressure loss on system

Torridge District Council are operating a KWB USV60 pellet fed biomass boiler which is used to supply heating to a number of office buildings via a heat main and underfloor heating circuits.  HPSL were approached to investigate recurring pressure drops causing the boiler to stop working.


Our initial investigation centred on the boiler and plant room as this was the only location with a pressure gauge.  The boiler was tested and found to be working correctly which allowed us then to focus more on the distribution aspects.  Over the course of the next few visits we carried out checks on the heat main and underfloor heating circuits, changing out faulty parts and leaking pipework along the way.  This also allowed us to install additional monitoring equipment in each of the offices to allow faster and more accurate fault finding should issues occur in the future.


As a result of the investigation and remedial work that was carried out by HPSL, the office heating has been restored to full working order and has allowed Torridge District Council to move forward with adding further offices onto the network and upgrading the boiler in the near future.


Client Testimonial


“HPSL provided extremely high levels of customer service during their investigations and remedial works, with swift response times and excellent handling of our third party tenants. They followed logical steps for fault correction, providing innovative low cost solutions to technical challenges while always keeping us informed”.