Hitachi ASHP monitoring configuartion

Dear all,

I’m new to the community of OEM. I have a Hitachi RASM-4NE heat pump (11kW monoblock) connected to panel radiators. I have an energy meter for the heat pump but it’s time to upgrade the monitoring system, for more analytical measurements (COP and water temperatures). In the following drawing is the configuration setup which I thought.

Let me do a quick rundown and how i thought it.

  • 3 phase energy meter for the heat pump. Not with CT clamps. Similar type as SDM120 (with Modbus communication, maybe SDM630?). Energy meter will be connected to EmonPI.

  • Heat meter (Kamstrup 403 with 240V power supply) which will be connected to EmonPI. I assume that flow and return temperatures (measuring points 1,2 in drawing) will be measured and transmitted from the heat meter?

  • Five (5) DS18B20 temp probes for measuring point 3 (buffer tank temp), points 4 and 5 (flow/return temp of the 2nd circuit), point 8 (boiler temp) and point 9 (external temp). All these will be connected to EmonPI.

  • Two (2) EmonTH with encapsulated DS18B20 (points 6,7) sensors for measuring temperature of the flow and return radiator header. The reason for using EmonTH is that the radiator headers are 20m away. EmonTH will be connected to EmonPI with an RF signal.

  • Energy meter for the circulating pump. This could be a CT clamp directly connected with EmonPI.

So, this is my approach and based on this i would like to see if this configuration is feasible. Any thoughts/suggestions are appriciated.

Thanks in advance,

Hi, welcome.

I can’t remember the limit on the emonPi, I think it is usually 3 without firmware changes, but I think the Heat meter may do the flow return temps.

That is a relatively expensive way of doing that. A WEMOS Mini D1 (or a Pi Zero if you can get one) with a couple of sensors would be much cheaper. The D1 is very easy to setup.

Nice diagram @nikara ! and welcome!

  • Yes a SDM630 with modbus output is a good approach.
  • Kamstrup 403 mbus output, great!

Do you have the emonPi and emonTH already?

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Good morning,

Dear @TrystanLea, maybe it wasn’t completely clear as I presented it. I don’t have emonPi or emonTH. In fact i don’t have anything for monitoring the heating system except from a 3phase energy meter (Qubino 3phase smart meter) for the heat pump. Now i’m trying to upgrade the heat pump monitoring system using OEM.
The basic configuration I have in mind is the one I have shown in the drawing and I would like to know if the equipment I have chosen can work.

Thanks a lot.