Advertorial  

The heating, ventilation, and air conditioning (HVAC) industry is in the midst of tremendous changes – spurred on in large part due to climate change efforts around the globe. This transformational period for the industry is being focused around an explosion of heat pump use as well as global shifts toward more environmentally friendly refrigerants.

Heat pump expansion

Electrified heat pumps are quickly replacing natural gas and oil-fired boilers – a key tactic in reducing the impact of climate change. Today’s heat pump designs can generate five times the heat compared to a traditional electric heater with the same amount of electricity – which allows them to overcome grid losses and create a net-negative impact on overall emissions from power generation.

Countries around the world have created a variety of incentive programs and regulations to push heat pump technology. Many countries – such as France, Austria, and the United Kingdom – have passed bans on installing as boilers in new buildings in the future. Other have created tax incentives and loan programs to help fuel the switch, or even looked at increasing taxes on fossil fuels such as natural gas.

Shift in refrigerant strategies

In addition to the growth of heat pumps, shifts in HVAC refrigerants have also been a focus area of the industry due to potential climate impacts.

Heat pumps and other HVAC platforms function by manipulating the pressure of a refrigerant to alter its temperature and change its state from a liquid to a gas. Different than a traditional air conditioning unit, however, heat pumps are bi-directional. The system can compress the refrigerant outside and cause it to absorb heat from an exterior source and bring it into the home to heat the air or hot water tank through the hydronic loop.  But it can also utilize a reversing valve to achieve the opposite – compressing the refrigerant inside the home to serve as a heat sink, cooling that air and transferring the heat energy outside during warmer months.

Various platform solutions around the world use a variety of refrigerants based on their specific application and other environmental needs.

While systems in past decade may have used hydro-fluorocarbon (HFC) compounds, the high global warming potential (GWP) of those refrigerants has led to the development of other options. Those shifts were behind the Kigali Amendment to the United Nations’ Montreal Protocol – legislation originally developed to ban chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), which were impacting the ozone layer in Earth’s atmosphere.

The dynamics of the shift have varied widely by region. Many systems across Europe utilize R290 (also known as propane) as the refrigerant, while others may utilize CO² or other refrigerant blends such as R454a (sometimes referred to as A2L refrigerants). These compounds are grouped under the term A2L because of their rating according to ISO 817.

Chemicals in category A3 are considered less toxic, but highly flammable – such as propane. While chemicals at B1 may not be flammable, they are toxic. A2L chemicals are slightly flammable but are less toxic.

A2Ls have been used in the European Union, Japan, India, Australia, and the auto industry for some time. But as the advantages of using A2L systems became more clear, regulatory bodies made adjustments to account for their use in commercial and residential HVAC systems, with regulations such as ASHRAE 15-2019 and UL 60335-2-40.

The sensors deliver a fast response time with a life expectancy of more than 15 years – often exceeding the lifetime of the equipment itself. Because the sensors do not require field calibration or re-zeroing, they reduce service costs for both installers and end users. They are also unaffected by fouling gases, HVAC cleaning solutions, and continuous refrigerant exposure.

Similar UL approvals are also needed for systems running on R290/propane. However, because propane is an A3 refrigerant – with a much tighter lower flammability limit – the detection systems for those equipment designs must be significantly more sensitive.

The road ahead

The elevated focus on HVAC as a key factor in climate change efforts is expected to continue in the coming years and decades, as commitments and deadlines made by countries around the world shift from long-term aspirational goals to practical, attainable targets.

While some of the stated targets and programs designed around them may shift due to new developments or other trends, the guiding principle of reducing the amount of energy used for heating and cooling of the next generation of electrified buildings will remain.

Sensata Technologies has discussed the transition to A2L/A3 refrigerants in a webinar focused on next‑generation sensor technologies enabling safer, more reliable, and regulation‑ready HVAC/R leak detection. Watch the on-demand webinar HERE.

https://www2.sensata.com/