The Energy-related Products Directive for water heaters

Stricter water heater energy efficiency limits were enforced on 26 September 2017, and the second lot a year later. We're taking a look behind the regulations, their meaning and what impact they may have for you.

The ErP Directive details – Ecodesign and Energy Labelling

The 2013 published Ecodesign and Energy Labelling regulations were one step towards achieving more energy savings. The regulations are roughly split into two parts (extract of water heater regulations only):

Energy efficiency of water heaters under the ErP Directive

Since 2015, increasingly stricter sets of minimum efficiency requirements for water heaters (excluding hot water storage tanks and solar water heaters) have been enforced. The minimum energy efficiency level that applies is dependent on the so-called “load profile” of a water heater, ranging from 3XS to 4XL.

What are ErP Directive load profiles for water heaters?

Every water heater meets at least one load profile, but the declared profile is either the maximum or one below the maximum load profile. Load profiles are based on a given sequence of water draw-offs in a 24-hour cycle that the water heater is able to provide.

Minimum energy efficiency requirements for water heaters under the ErP Directive

Since 2015, increasingly stricter sets of minimum efficiency requirements for water heaters (excluding hot water storage tanks and solar water heaters) have been enforced. The minimum energy efficiencies for 2017 can be seen in the table below.

These minimum energy efficiency levels that apply are dependent on the so-called “load profile” of a water heater, ranging from 3XS to 4XL. Every water heater meets at least one, but the declared profile is either the maximum or one below the maximum load profile. They are based on a given sequence of water draw-offs in a 24-hour cycle that the water heater is able to provide.

All of Hamworthy’s water heaters already meet the Tier 3 efficiency levels set for 2018.

Energy labels

Required for all boilers up to 70kW and water heaters and storage tanks up to 500l, ErP energy labels have been required since September 2015. Originally rated from A to G, an update in September 2017 saw the ratings adjusted to run from A+ to F for water heaters. Read more about energy labels.

Nitrogen oxide (NOx) emission limits for water heaters under the ErP Directive

NOx emissions are a contributor to smog and therefore poor air quality. For this reason, NOx emission levels will also be enforced for water heaters from 26 September 2018. For conventional water heaters, the limits are 56 mg/kWh (gaseous fuels) and 120 mg/kWh (liquid fuels). (Given as fuel input in terms of gross calorific value (GCV). Different levels apply to heat pump water heaters which are not covered in this article.)

Storage volume and sound power level of water heaters under the ErP Directive

In 2015, storage volume limits and minimum amount of stored water at 40°C were enforced. For heat pump water heaters, maximum sound power level limits were introduced in the same year.

Standing losses of water heaters under the ErP Directive

Limits for standing losses (heat lost to the environment = wasted energy) for hot water storage tanks and solar water heaters were introduced on 26 September 2017.

What are standing losses?

Standing losses are heat lost to the environment which = wasted energy. The bigger the tanks, the bigger the heat loss. That’s why our calorifiers are supplied with an insulation jacket to keep the heat in the system and minimise standing losses.

Timeline of ErP Directive changes