A solar thermal service by Griffiths ensures your system is operating efficiently and providing the maximum benefit from the sun's energy.

Griffiths to repair evacuated tube collectorGriffiths to repair solar thermal pump stationGriffiths to repair solar thermal controllerLarge solar collectors to be flushed

Solar thermal systems are fairly simple with few working parts, leading them to be described as a 'fit and forget' technology.

Griffiths, however, feel this can be misleading...The technology is low maintenance, due to there being only a few moving parts, however if the key components are not correctly maintained the system can become inefficient and potentially fail.


Solar Heat Transfer Fluid - A solar thermal system utilises a Propylene based heat transfer fluid to collect heat energy from the collector (usually roof mounted) to heat the hot water cylinder (Via a secondary heating coil). 

The Propylene glycol is vegetable based (To prevent harm if leaked) and starts to degrade after 5 years. 

Therefore as part of our service the solar fluid is tested (To check its antifreeze properties) and replaced if necessary. Degraded heat transfer fluid becomes a sticky sludge like substance, which is inefficient at collecting and transferring heat energy.

Circulating Pump - Within the solar pump station is a circulating pump. This circulates solar fluid between the roof mounted collector and heating coil within the hot water cylinder. It is essential that the circulating pump is operating correctly to allow efficient movement of the solar fluid and transfer of heat energy.

Degraded (Sludge like) solar fluid is more difficult to circulate around the solar systems pipe work services, resulting in wear on the circulating pump.

System Controls - Solar thermal systems operate via a controller sensing temperature differentials, i.e.... when the solar collector is hotter than a property's hot water cylinder, the system (Circulating pump) is activated.

It is therefore essential to determine that the system's thermistors are correctly registering temperatures operating the system's pump.

Expansion Vessel - 'Pressurised' solar thermal systems have an 'expansion vessel' to allow for the expansion of the solar fluid within the pipe work services. It is essential that the expansion vessel pressure is tested for correct operation, taking up the expansion of the fluid, otherwise the system risks going over pressure (Resulting in solar fluid loss, via the pressure relief valve).