THZ / LWZ Tecalor Stiebel Eltron Heizung

[houseowner123]

Of course. How should the THZ know about replacing the heat exchanger against the bypass?

I have a theory that I still need to test. If true, the thz could know whether the by-pass is in place. But probably the engineers didn't care because the average use would never want to know about this anyway.

[willybauss]

exactly. What we do here is at least 120% above the THZ developers' expectations  .

[willybauss]

@ houseowner123:
Can you confirm meanwhile that the heating curve is influenced by the inside temp. sensor? To test it you can simply heat up the sensor using e.g. a hair dryer, and then watch the heatSetTemp value. It should decrease.

I'm asking because I observed a strange behavior: I do not just have an inside temp. sensor, but additionaly a second display in living room, which has a built in inside temp. sensor as well. So now the question was, which of both is being used by the THZ control. The answer is: both.

   
• the inside temp sensor's value is shows in  sGlobal:insideTemp; no further functionality observed
• the second display's  inside temp sensor's value is used for calculation of the heating curve, but is not shown in any one of the readings values (as far as known so far)
• the second display's  inside temp sensor's value is shown as inside temperature in both displays (second one and the one built in into THZ front panel) 

To get rid of this curious situation I tried to obsolete the inside temp sensor, but without success. As soon as I removed it, the sGlobal:insideTemp value was -60°C always, though I had expected it to be filled by the second display's sensor value instead.

@immi:

Looks like there is another hidden value to be read from the THZ, representing the inside temp. value of the second display. Do you have an idea where it might be located?

[immi]

Hi Willy
no idea because I do not have the hardware to test it
have a look in register E8; just uncomment line 273.
Heat up your living room display and read again E8

or maybe someone can lend you an oscilloscope and you can look at the can-bus of the display
immi

[houseowner123]

The results are in after exactly 7 days of measuring: actual Meter reading: 15 kWh
sElectr.DHW change: 9 kWh, sElectr HC change: 0 kWh
Ventilation stage 1 for 24/7 + powering the: 36 W.    36 W x 24 hr x 7 d= 6 kWh
Sum: selector.DWH change+ventilation+powering= 15 kWh
Q.e.d.   THZ module measures are correct sElectrical values!

Remarks: I can measure real time power usage, so here are some values for the ones that are interested (303i):
Powering and controlling: 12 W
Air vent stage 1- winter cassette: 24 W
Air vent stage 1 - summer cassette: 13 W
Air vent stage 2 - summer cassette: 25 W
Air vent stage 3 - summer cassette: 45 W
HC Compressor:  54 W
DHW pump: 1500 W

The heat produced - sHeatDWh was 27 kWh - as predicted 1:3 efficiency
sHistory reported: 5 hours of DWH compressor activity. I think there must be a rounding error here because it should be 6 hrs according to all available data.

In addition I hypothesize that the summer cassette decreases the fan speeds due to lack of forced heat exchange. The flow, if I could only measure it, should be the same no matter which cassette is in there because the flow rates are set. So the summer module saves 11 W. So within the THZ lifetime it will eventually amortize.

Does anyone else have actual metering on the Thz? I envision that if we could somehow determine actual activity time across 24 he's of compressor, vent stages, heat pump and booster activity, that this module can give you exact meter reading ( actual total system usage) of energy for any given day.

@willy: the sensor is still in the cool basement. Need to extend the chord. Will check the heating set point change and report back.

Tom

Tom

[immi]

nice overview tom!!

[lwzler]

@houseowner123

Thank's a lot for your work and the impressive values.
Especially the section on the power consumption summer cassette <-> winter cassette was very interesting!

[Jakl]

Hi,

I already got this module up and running with my LWZ 303i. But now I've got some questions, maybe you can answer me.

1. How do you get the inside temperature? I do not have any inside control or temperature sensor from stiebel inside my house.
2. And how do you get the humidity? Is that also a sensor in the house or is it an internal sensor of the THZ/LWZ?
3. Do you all have power and heating measurement within your LWZ/THZ? Can that be installed additonally?
4. What is the last firmware version for an LWZ 303i?

@houseowner123:
You wrote:

I can measure real time power usage,

Can you tell me/us, how you do that? I'm planing to do the same, but at the moment I have several ways in mind and can't decide the best (low cost, high output). And I would like to know, how much energy kWh you need with your 303i over a year. You can write me an PM, if that's fine with you. 

Best regards,
Jakl

[micomat]

1. How do you get the inside temperature? I do not have any inside control or temperature sensor from stiebel inside my house.
2. And how do you get the humidity? Is that also a sensor in the house or is it an internal sensor of the THZ/LWZ?

both sensors are inside the control panel which you don't have. me not either, so i installes the HMS100TF using a CUL868 for this measurings.

3. Do you all have power and heating measurement within your LWZ/THZ? Can that be installed additonally?

yep, they are coming from the system itself.

4. What is the last firmware version for an LWZ 303i?

for the 303 i guess 4.39
for the 403 i already saw a 5.39

markus

[willybauss]

cheapest way for measuring inside temp with THZ (!) is an external sensor, connected via a 2 wire cable. Advantage of measuring it with THZ is that you can select to influence the heating curve in this case. Of course that's not possible with different inside temp measuring methods since the THZ doesn't know about it. Humidity needs a secondary display in living room and it can measure inside temp as well.


power and heating measurement is built in into THZ/LWZ. See "ISTWERTE" and "FACHMANN - LAUFZEITEN" menu for available values.

[micomat]

Willy, why Not? you can change the Set temps depending on the measurement of the hms100tf

[immi]

Willy, why Not? you can change the Set temps depending on the measurement of the hms100tf

http://fhem.de/commandref_DE.html#THRESHOLD could help you

[micomat]

Not what i meant but Never mind

[immi]

http://fhem.de/commandref_DE.html#THRESHOLD could help you

Hi Markus
My understanding is that you want to change the Set temps in the heatpump depending on the measurements of hms100tf.
I would't do a linear feedback (continuous set of values)
I suggested you threshold, because it could help you with a quantized feedback (relatively small discrete set).

immi

[micomat]

and i suggested the HMS to jakl
but the idea with threshold is good.

thanks
markus