The efficiency and performance of solar thermal systems and heat pumps depend on the quality of the thermal fluid they use. Water treatment is an essential part of maintaining these systems.
The heat transfer fluid in solar thermal systems is a glycol mix, which can degrade over a period of a few years. In order to maintain the performance and efficiency of these systems and limit damage, the degraded glycol needs to be drained off, the system cleaned and new fluid introduced.
Dirty water and soil can contaminate ground and air source heat pump systems. If bacteria enters the system, the glycol acts as a nutrient source and this together with low temperature enable bacterial proliferation.
This can ultimately lead to the degradation of the glycol and the formation of deposits which can decrease the system's efficiency.