The EP001 wiring centre is cleverly designed to bring together and simplify the wiring connections of a multi-zone control system for an air source heat pump and house them in one single enclosure. Here, we take a closer look at how the Grant EP001 wiring centre works.
Benefits of a heat pump wiring centre
Using the EP001 wiring centre from Grant UK, installers can centralise the wiring for up to four heating zones and one domestic hot water zone making it ideal for both new and retrofit heat pump installations. The Grant EP001 wiring centre provides a convenient solution for multi-zone wiring for Aerona³ heat pumps by:
- Simplifying the wiring for more than one heating zone and the DHW zone
- Indicating whether a zone is active or not via indicator LED lights
- Incorporating built-in DHW priority.
Please note, the EP001 wiring centre is compatible with the Aerona³ R32 heat pump range only – it is not compatible with Grant Aerona 290 models.
What is the EP001 multi-zone wiring centre?
The EP001 wiring centre greatly simplifies the wiring associated with a multi-zone heat pump heating system. It consists of a printed circuit board housed in an electrical enclosure and white casing designed to be fixed straight to the wall inside a cupboard or heating plant room for example.
How does the EP001 simplify wiring?
The EP001 has the following features which ease the wiring set-up for heat pump installers and electricians:
- The EP001 has the capacity for up to four separate space heating zones, each one of which can be independently controlled, as well as one hot water zone.
- These five zones are each separately and clearly marked on the circuit board making the wiring for these zones tidy, clear and straightforward.
- For each of the space heating zones, there are three pairs of terminals for the timer, thermostat and power output to a zone valve or pump, each with clear markers making them easily identifiable as well.
What are the indicator LEDs?
Alongside each heating zone on the circuit board, there is a LED light which indicates whether or not that zone is active. If the zone is active, as a result of the timer and thermostat signalling demand for space heating, the red LED light will be on. These LED lights allow installers and service engineers to easily identify which zones are active at any time to see the operating status of the system, assisting with diagnostics if required.
Built-in DHW priority
Two further features are also available with this wiring centre:
- The EP001 provides the volt-free switching required to operate the space heating and domestic hot water functions of the Grant Aerona³ heat pumps.
- The EP001 also has built-in domestic hot water priority capability operated via the priority switch on the circuit board. With this function switched on, when a demand for hot water is present, the hot water priority control will automatically interrupt the space heating so that the hot water requirements are fulfilled quickly and efficiently.
This integral DHW priority function of the EP001 will mean that installers do not need to fit a separate DHW priority relay, simplifying the installation and saving time.
How to order the Grant EP001
The EP001 wiring centre is available to order alongside all of Grant’s Aerona³ heat pumps – to discuss the range further, please do not hesitate to get in touch with a member of our Sales Team or read more about our heat pumps here.
This blog was originally published on 18th February 2021 and updated on 9th July 2025.
