Most heat pumps has an electrical terminals where you can connect an external device that can control its state block certain parts of pump operarations. This is often used for power guards oar Tariff steering that can turn off Additional heat or the whole pump operations to avoid main fuses to blow.
In the heat pump you often have settings where you configure reactions when this port is going active. Normally this is set to block additional electrical heater, block kompressor or both. But some pumps has many more options.
For H66 there are an optional cable that can be ordered which can be connected to control this port. The solution can control up to 2 ports. Tha cable features an optical isolation between H66 and the EXT port.
This solution has not been tested on all pumps so far but should work on most pumps.
Why do I need this cable? This cable provides more options for controlling some pumps, and usage does not write to the pump flash memory so you can perform frequent changes without worry about having any future problems. This cable is for you that frequently modifying operational parameters.
Disconnect H66 from your pump and remove its interface card.
Close the lid and carefully drill a 3,5mm hole 17mm from the current hole (in parallell with the EXP socket ) for the cable to exit with lid closed.
In the H66 Config meny, set EXP_PORT to EXT
Now you should see 2 additonal variables. These can be set to 0 or 1 where 1 is Active.
These can then be controller from H66 scheduler, GRID Price control or from your Home automation.
Use the Insatallation manual of the pump to find the EXT terminal. Here we have a few examples.
IVT Greenline HT, Rego 600
This pump has One EXT port which can be programmed in service menu 5.7 to block Additional heater, Compressor and Hot Water production. It is easy to install with just 2 cables
IVT Greenline HE, Rego 1000
This pump has Two EXT ports which can be programmed in service menu 8 to block Additional heater, Compressor, Hot Water production and many more options. It is easy to install with 2 cables for each port.
IVT / Bosch Rego 2000/3000/3100 LW Pumps (Geo)
This pump has 4 EXT ports that can be programmed in service menu to block Additional heater, Compressor, Hot Water production and many more options. It is easy to install with 2 cables for each port .
NIBE EB 100 F-series pumps
This pump has 5 EXT ports called AUX, which can be programmed in service menu to block Additional heater, Compressor, Hot Water production, switch to economy mode and many more options. It is easy to install with 2 cables per port.