The importance of Blygold treatment for air source heat pumps
The importance of Blygold treatment for air source heat pumps

Heating engineers who install and service air source heat pumps in coastal regions should be familiar with the requirement to treat heat pumps and their core components with an appropriate anti-corrosion treatment. In this blog, Grant UK’s Renewable Sales Manager, Kevin Ellis, takes a closer look at Blygold treatment for heat pump units.

If you refer to the guarantee terms and conditions provided by heat pump manufacturers for their products, you will likely come across a requirement for the unit to be suitably treated against corrosion if it is sited in a location near to the sea. Failure to do so can invalidate the guarantee while also impair the long-term performance of the heat pump itself. Understanding the importance of anti-corrosive treatments, such as Blygold, is therefore worthwhile for heating engineers who work with heat pumps near to the coast.

Why is Blygold treatment necessary?
Heat pumps installed at properties located close to the sea can be prone to corrosion damage as a result of being exposed to the sea air. This is because the salt within the air will increase the likelihood of corrosion of the evaporator coil through which the air is drawn within the heat pump. If untreated, heat pumps which are installed near the coast can have a reduced lifespan and reduced output, so it is vital that appropriate anti-corrosive treatment is applied to the unit.

This is where Blygold treatment steps in. This coating can be applied to the evaporator within the air source heat pump, providing anti-corrosion protection designed to preserve the heat pump against the sea air. The Blygold PoluAl XT coating is polyurethane impregnated with Aluminium. It seals off the dissimilar materials of the evaporator coil (copper tubes and Aluminium fins) from the atmosphere to prevent product failure and unnecessary energy consumption which can be caused by corrosion. The Aluminium in the coating ensures no reduction in heat transfer and may actually enhance it. As the coating is Hydrophobic it repels water, and this helps to prevent dirt adhering to the evaporator fins and reducing the coil efficiency.

To maintain the benefits of the Blygold coating the evaporator coil should be periodically cleaned. Any dust and debris should be removed from the coil face by either a soft brush or gentle vacuuming and then washed with a mild coil cleaner (detergent) or plain water using a low-pressure jet wash.

How often should a heat pump be treated?
A suitable anti-corrosion treatment should be applied to a heat pump prior to the unit being commissioned if the unit is being installed within two miles of the sea. Grant Engineering specify that, if Blygold treatment is not opted for, the evaporator must be sprayed with ACF50 during the installation and then this must be repeated at each annual service after cleaning the evaporator coil in the same way as for the Blygold coating. For installations where Blygold treatment is selected, the Blygold coating can be applied prior to installation and then no further treatment is required.

Can Grant supply Blygold treatment for their Aerona³ heat pumps?
All of Grant’s Aerona³ air source heat pumps can be supplied to site pre-treated with Blygold. This treatment can be specified on an installer’s order with their merchant using either the code BLYGOLD1 (for Aerona³ 6kW and 10kW models) or BLYGOLD2 (for Aerona³ 13kW or 17kW models). Upon receipt of such orders, the Aerona³ heat pump evaporator coil is treated with the Blygold PoluAl XT coating. The Blygold treated Aerona³ unit is then delivered to the merchant ready for the heating engineer to install with no further anti-corrosive treatment required.

In conclusion
It is imperative that air source heat pumps installed within the vicinity of the coast are treated with an anti-corrosion coating or spray. The definition of ‘vicinity’ within this context can vary according to different heat pump manufacturers but for Grant Engineering, any property located within two miles of the sea would be classified as being within the vicinity of the coast and would therefore require appropriate treatment. If you are a heating engineer working within such areas, you should therefore discuss the necessary anti-corrosive treatments needed for heat pumps with your customers, ensuring that the longevity and performance of their units is protected for years to come.

Kevin Ellis
Renewable Sales Manager at Grant UK