I have been looking / wanting to add proper monitoring to my recent ASHP install.
I’m a bit unsure which heat monitor I’ll need though as my ASHP falls into 2 categories. So before ordering I want to check that I’ll need the 15kW heat meter as my flow rate can be high, though I believe my ASHP is rated at 5kW.
Technical details on the ASHP are here, I have the PRO-N variant.
The Sontex 789 that we recommend for up to 7kW heat pump will be fine for your 5kW system. To deliver 5kW at DT5 your flow rate will be maximum about 15L/min (0.87 m^3/hr). The maximum flow rate quoted on the datasheet for your heatpump will be the maximum flow rate the heatpump can handle without getting sustaining damage!
At 15l/min the Sontex 789 has a pressure drop of 0.25m which is negligible.
It’s great you’re considering adding monitoring to your Acond ASHP, this is a very interesting unit, a European manufactured R290 heatpump. How are you finding the control system?
That’s cool, it’s good to see more info is available via modbus. However, the parameters available via modbus look to be quite limited. There’s not enough information available to calculate COP.
To calculate COP we need flowT, ReturnT, flowrate and electricity input. As far as I can see only flowT and returnT are available via modbus direct from the heat pump.
Update: I’ve just seen that comp_capacity_actual looks like heat output in W, this metric coupled with electrical input is all you need to calculate COP. However, there’s no guarantee of accuracy using manufacture’s metrics compared with a MID approved heat meter, however it may be a useful starting point.
I like the look of the web interface, that’s so much better than fiddling with the LCD controller that most HP use.
I think the best course of action would be to get the kit from yourself, as like you say it will be consistent (with heatpumpmonitor.org) So will look at getting the kit as soon as I am able.
Indeed a web page is so much easier and user friendly. The installers and ACOND themselves also have direct access to this as well. Friends have a Panasonic, the controls on that aren’t great to say the least.