How to use the HeatPump Module

add the app as i want to experiment with the heat pump module

is it normal that initial text is repeated?

I moved this to a new topic as it is a different question (to which I do not know the answer :smile:).

no problemo :smiley:
just seems odd to me
also the fields could use some short explanation, the 2 first i can guess

watts the heatpump use
next is the same but in kw/h
but heatpump_heat is an unknow
heatpump_heat_kwh, what is that?
flowT and return are temps i can guess that, the first must be inlet and the other outlet?

In terms of a boiler, “FLOW” is the hot water going to the radiators etc, “RETURN” is the colder water that has lost its heat and is coming back to be reheated.

yep, those i guessed, but what about the other ones?

Sorry, I know nothing about the Heatpump module.
If I could find the ESP source code, I could trace it back. But I can’t find that.

or maybe our fearless leader @TrystanLea knows?

No that’s an error.

This is an app and has nothing directly to do with a heatpump, other than to display the metrics normally associated with a heatpump. Those metrics may be sourced from a variety of places, modbus for example, or mbus etc. Or they might just be roughly calculated in emoncms eg if a heatpump has a COP of 4:1 and it is consuming 2kW of electric, it will be pumping out an average of around 8kW of heat (Third metric heatpump_heat) and if it does that for 5hrs, it will have produced around 40kWh’s of heat (Fourth metric heatpump_heat_kwh). Obviously there are better ways of getting this value, the norm is to use a heat meter, which is a sensitive flow sensor with 2 matched and calibrated temp sensors to measure temp in, temp out and flow to accurately determine the heat produced, but very few installs have a heat meter as they are fairly expensive as a rule.

[edit] I’m not suggesting that electricity consumption and heat output are rigidly tied as they are not, due to things like ground/external temps etc. But it can be a reasonable indication. The app is specifically aimed at tracking that efficiency by comparing power used to heat produced, so the app is only fully utilised if a accurate heat value can be sourced. The OEM heatpumpmonitor uses Mbus to get that data from certain (kamstrup?) heatmeters.

i did plan use a flow sensor (with hall effect sensor) and 2 ds18b20’s, i know its not super precise but i guess it could give a good estimate

i plan to use the heatpump math for a pool monitoring project, adding some solar mats and a very low flow rate pump to circulate the water slowly though the mats to get as much sun energy out of them

and partly i wanted to figure out how much energy i put in the water, and do a very rough estimate on how long it would take to heat X liters of water to Y temp

i posted about that part here: Calculate energy added and time to get to temp - #27 by boelle

last post mostly sums it up with formula’s needed. and it was here that the heatpump part was suggested, but now i think maybe i can do without that and just have it calculated by emoncms,

and since i have emoncms on shared hosting it would be interesting to see if i can run python scripts. but i know for sure i can run php scripts so one way or the other i can get the math done

Will the low flow rate help? Yes, you will get a higher temperature, but I don’t think you will get any more heat. In fact, I would have expected higher losses because there’s a higher temperature difference between the pipe and ambient on the pipe running from mat to the pool, and between the mat and ambient. As soon as the hot water hits the pool, it will give up its heat almost immediately anyway.

If you used a small solar panel to drive the pump it would be totally free energy (running costs) and operate autonomously too, ie the pump would only operate when the sun was out and heating the solar mat. Add a small battery to keep it running during cloud cover and to get that last bit of heat out of the mat at sundown.

The ds18b20’s will be fine for what you want to do, but you will need to compare the 2 sensors side by side across a range of temps and then perhaps “calibrate” one to the other with a slight adjustment in code.

nope, but its the pump that came with the pool, i fitted a surface skimmer 2 days ago and now that pumps is to “weak”, so will buy a pump with much higher flowrate to keep the pool clean and the use the “weak” one exclusive for solar, and i can turn it off when sun is not up

missed this one, but sadly the pump is 230V(mains), but will try and cook up something that can figure if sun is up and turn on the pump, and turn it off when sun is down and when the inlet and outlet is the same temp