Hi, I’m a technical software developer just getting started in this space. Trying to figure out where to start with heat pumps - I see Daikin and Valliant a lot. I’ll be installing OpenEnergyMonitor and connecting to HomeAssistant. I can see that there are various interfaces to the heat pumps - b…

Hi Martin, The challenge with making any general statements about APIs is that they’re all manufacturer-specific. However, it’s clear that the big manufacturers have all responded to users’ expectation of having a smartphone App for monitoring and controlling their heatpump - so they provide an App…

Thanks :slight_smile: The downside of re-using an App API is that they could block it, I guess :slight_smile: I’ll do more research on the forum, see what I find!

Hi @mgg1010 Martin, There are quite a few threads here on controlling various Samsung heat pumps, mostly by modbus or Samsung’s own propriety NASA (Network and System Architecture) protocol.

Grant R290 heat pump has a fully local HTTP API which is really nice and easy to integrate with: [image] Reading onboard data from Grant Aerona HP290 + Control Heatpump The Grant Aerona HP290 heat pump uses a Plum ecoMAX360i touch screen controller. It’s a goo…

Thanks @Old_Scientist @glyn.hudson - much appreciated. I’ll take a look at those too :slight_smile:

Can anyone summarize heat pump API status?

Hardware Heatpump

glyn.hudson (Glyn Hudson) 7 April 2026 11:45 5

Grant R290 heat pump has a fully local HTTP API which is really nice and easy to integrate with:

Manufacturer cloud APIs should never be relied upon.