One of the questions we often get asked after installing a solar thermal system is what happens if I go on holiday?

It can be a problem as with no demand for hot water at the sunniest time of the year your system may be suffering. After the first day away the chances are that your well insulated solar cylinder will be 'satisfied' – ie up to temperature. Because the cylinder is well insulated it will stay this way overnight, and because there is no one to have a shower or use hot water in the morning, it will still be satisfied at the sunniest times of the day. The solar collector will get hotter and hotter but that heat won't go anywhere because the cylinder is up to temperature. Sitting at high temperatures for hours each day will reduce the life of the solar fluid and may cause a build up of residue in the pipework.

So what can you do about it?

Most controllers built over the last 10 years have a holiday function or 'recool' function. If you set this function to 'on' the pump will run at night. Running the pump at night sends heat from the cylinder to the collector. Effectively this runs the system in reverse until the cylinder is cool again. This means that the next day the cylinder has the capacity to take more heat and the collector won't overheat – or if it does it won't be for a prolonged period. If your controller does not have this function all it's worth asking a neighbour to pop in and run some hot water off if the forecast is for sunshine!!!!

If you go away alot another option is to go for the HFC curtained solat thermal collector (pictured) this has an auto blind fitted which covers the panel once the cylinder as reached temperature, please contact us for more infomation about this option