@iancalderbank Hi Ian, yes I do have a strong feeling of achievement coupled with a bit of sphincter loosening 🙂 Actually its my second, I popped my cherry on an Ecoden about 12 years ago when I did a self build. Despite my limited knowledge at the time it all worked out well!

I have 2 other installation manuals, but I was hoping for something a bit more user friendly with regards to setting the controller up. I wonder if there are 2 more in the outside unit somewhere 😮

I only have my unit set up for heating, using the thermostat on the display. I have set up weather compensation (Heat Law) and it all seems to work. I found Grahams/Freedom Heat Pumps videos very useful although there was an error in video 12 regarding the entry of the high and low figures (202) in the video they seem to be the wrong way around. Given that Im wondering if the display should say 30 degrees or something else (worrying), although the input water temperature matches my heat law curve perfectly.

I know the advantages of running the HP 24/7 but with solar panels the temptation is to lose a bit of efficiency in the morning because I have free electricity then anyway. So it can make sense to turn it off overnight. I have looked at homely and am impressed although Im happy to have a stab at Home Assistant too if necessary. I havent come across evohome before.

As for the sphincter loosening, it turned out the heat was supplied with a disconnected fan. I had to open it up and connect it! This morning I have also hit an E912 error which looks to be a sticky relay causing the pump to stay on when no heating is being drawn. I found a very good entry on it on buildhub.

Thanks for the reply, Mark

@bontwoody I'm glad you noticed that one  as well I went back and checked that one for the 202x settings 4 times, before I was finally convinced by a sudden cold snap that weather comp was working the wrong way round!  wondered if I'd misread something but if you think its the wrong way round as well, then one to message graham about . for the controller setup, that manual about all you get. so its asking on here, youtube, etc. you can however signup for the basic installer training on samsung partner portal (Free, 1/2 day online, I did it) and you get some more useful docs.

I have a strong preference to turn it off at 2300. we like a quiet house overnight and we like cool rooms for sleeping. then with cheap intelligent octopus leccy turn it on full blast for downstairs at 0430, upstairs at 0630. works out better so far . but I've not run through winter - only been live a month - so maybe eating my words in 7 months!

evohome is a programmable TRV system with controls oriented at gas boiler setups. I got it 7 years ago for the boiler.  If I wanted to re-do programmable TRV's again I wouldn't buy evohome for a heat pump system. the control output isn't suitable - its far too keen to be "off" (To save gas). so I don't use its control output. and the TRV's are eyewateringly expensive now, and they've not updated the controller for years. so yes for the concept but no for the specific system if you were going shopping now.

post photo of your display?

@iancalderbank LOL to be absolutely honest I didnt pick up on it, but saw another post when I was looking for tips. I went back and checked and what was said made more sense with the two sets of numbers in the same relative position on both settings. I was going to message Graham to tell him but comments were turned off. Did you have to fib about being a business to get the training?

Im still on a very cheap tariff from two years ago, so havent really investigated that side of things yet, but will do before it comes to an end in september. I think i will have substantial export over the summer so Im definitely motivated.

I have basic TRVs on some radiators but havent really investigated the effect on flow rates yet and they are all wide open.

Pictures attached. Thanks Ian

Posted by: @bontwoody

↑

@iancalderbank LOL to be absolutely honest I didnt pick up on it, but saw another post when I was looking for tips. I went back and checked and what was said made more sense with the two sets of numbers in the same relative position on both settings. I was going to message Graham to tell him but comments were turned off. Did you have to fib about being a business to get the training?

Im still on a very cheap tariff from two years ago, so havent really investigated that side of things yet, but will do before it comes to an end in september. I think i will have substantial export over the summer so Im definitely motivated.

I have basic TRVs on some radiators but havent really investigated the effect on flow rates yet and they are all wide open.

-- Attachment is not available -- -- Attachment is not available --

 

Pictures attached. Thanks Ian

graham is on this board so we can both message him the same thing through here!

training - the supplier that I bought from said samsung are happy for anyone to go on it, just go ahead and register - so I did. I did use my business email address to register though. they asked no "who are you" questions when I registered or during. TBH the training wasn't anything to get over excited about - if I'd paid for it I'd have been disappointed - but it was "ok". PM me an email and I'll send you some notes.

I do believe that screen is saying that the target ROOM temperature in the location of the panel is 30C, and the actual is 19.8.  so you probably wanna turn the target down , unless you want always-on. The panel acts as a room thermostat to turn the whole thing on and off. and its saying the LWT of the heat pump is 38.0, which is a reasonable number.

rads - yes. I've not balanced yet either. been putting temperature probes in various places and I know its out of kilter. that will be the next mission. 

@iancalderbank Thanks Ian, I think I have PMed you, let me know if you dont get it. Always on is fine TBH I think my weather compensation curve is set to 35 at 15 outside and 45 at -2 so given its about 12 deg outside now, 38 is about spot on I would guess 🙂 Good to have the reassurance what I thought was happening, was. I emailed homely to see if they would let a diyer use the installer app to set up their device. The price point is very good £184 given the samsung MIM board is included and retails at £136 all on midsummerwholesale.

so, found time to get back to this now. my house is fully on the ASHP including DHW, and I've installed an ESP32 board to talk to the modbus controller in place of the ESP8266 I was using , just in case horsepower was an issue.

unfortunately, the behaviour is still exactly the same - when I change the value of the HA "number" for DHW target, I see the ESP get the change from HA, then a few seconds later the system changes it right back. I don't know where this change back is coming from. 

to those who have this working please, what am I doing wrong?

[17:14:15][D][number:012]: 'DHW Target Temperature': Sending state 55.000000
[17:14:16][D][modbus_controller.sensor:025]: Sensor new state: 711.00
[17:14:16][D][sensor:127]: 'DHW Temperature': Sending state 71.10000 ºC with 1 decimals of accuracy
[17:14:16][D][uart_debug:114]: <<< 01:03:08:00:00:00:01:02:26:02:C7:08:96
[17:14:16][D][uart_debug:114]: >>> 01:03:00:4E:00:02:A4:1C
[17:14:16][D][number:054]: 'DHW Target Temperature' - Setting number value
[17:14:16][D][number:113]:   New number value: 54.000000  <<<<< NEW VALUE COMES FROM HA
[17:14:16][D][modbus.number:061]: Updating register: connected Sensor=DHW Target Temperature start address=0x48 register count=1 new value=54.00 (val=540.00)
[17:14:16][D][number:012]: 'DHW Target Temperature': Sending state 54.000000
[17:14:16][D][uart_debug:114]: <<< 01:03:04:00:00:00:00:FA:33
[17:14:16][D][uart_debug:114]: >>> 01:03:00:57:00:01:35:DA
[17:14:16][D][modbus_controller.sensor:025]: Sensor new state: 0.00
[17:14:16][D][sensor:127]: 'Flow Rate': Sending state 0.00000 lpm with 1 decimals of accuracy
[17:14:16][D][uart_debug:114]: <<< 01:03:02:00:00:B8:44
[17:14:16][D][uart_debug:114]: >>> 01:06:00:4A:02:1C:A8:B5
[17:14:16][D][number:012]: 'DHW Target Temperature': Sending state 54.000000
[17:14:16][D][uart_debug:114]: <<< 01:06:00:4A:02:1C:A8:B5
[17:14:16][D][number:054]: 'DHW Target Temperature' - Setting number value
[17:14:16][D][number:113]:   New number value: 53.000000
[17:14:16][D][modbus.number:061]: Updating register: connected Sensor=DHW Target Temperature start address=0x48 register count=1 new value=53.00 (val=530.00)
[17:14:16][D][number:012]: 'DHW Target Temperature': Sending state 53.000000
[17:14:16][D][uart_debug:114]: >>> 01:06:00:4A:02:12:29:71
[17:14:16][D][number:012]: 'DHW Target Temperature': Sending state 53.000000 
[17:14:16][D][uart_debug:114]: <<< 01:06:00:4A:02:12:29:71
[17:14:25][D][uart_debug:114]: >>> 01:03:00:02:00:01:25:CA
[17:14:25][D][uart_debug:114]: <<< 01:03:02:00:00:B8:44
[17:14:25][D][uart_debug:114]: >>> 01:03:00:04:00:02:85:CA
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 0.00
[17:14:25][D][sensor:127]: 'Compressor Frequency': Sending state 0.00000 Hz with 0 decimals of accuracy
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 117.00
[17:14:25][D][sensor:127]: 'Outdoor Temperature': Sending state 11.70000 ºC with 1 decimals of accuracy
[17:14:25][D][uart_debug:114]: <<< 01:03:04:00:00:00:75:3B:D4
[17:14:25][D][uart_debug:114]: >>> 01:03:00:34:00:01:C5:C4
[17:14:25][D][uart_debug:114]: <<< 01:03:02:00:01:79:84
[17:14:25][D][uart_debug:114]: >>> 01:03:00:3A:00:01:A4:07
[17:14:25][D][modbus.number:023]: Number new state : 18.00
[17:14:25][D][number:012]: 'Target Indoor Temperature': Sending state 18.000000
[17:14:25][D][uart_debug:114]: <<< 01:03:02:00:B4:B8:33
[17:14:25][D][uart_debug:114]: >>> 01:03:00:41:00:02:94:1F
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 198.00
[17:14:25][D][sensor:127]: 'Return Temperature': Sending state 19.80000 ºC with 1 decimals of accuracy
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 201.00
[17:14:25][D][sensor:127]: 'Flow Temperature': Sending state 20.10000 ºC with 1 decimals of accuracy
[17:14:25][D][uart_debug:114]: <<< 01:03:04:00:C6:00:C9:DA:58
[17:14:25][D][uart_debug:114]: >>> 01:03:00:44:00:01:C4:1F
[17:14:25][D][modbus.number:023]: Number new state : 26.00
[17:14:25][D][number:012]: 'Target Flow Temperature': Sending state 26.000000
[17:14:25][D][uart_debug:114]: <<< 01:03:02:01:04:B8:17
[17:14:25][D][uart_debug:114]: >>> 01:03:00:48:00:04:C4:1F
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 0.00
[17:14:25][D][sensor:127]: 'DHW Status': Sending state 0.00000  with 0 decimals of accuracy
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 1.00
[17:14:25][D][sensor:127]: 'DHW Mode': Sending state 1.00000  with 0 decimals of accuracy
[17:14:25][D][modbus.number:023]: Number new state : 55.00
[17:14:25][D][number:012]: 'DHW Target Temperature': Sending state 55.000000 << AND THE SYSTEM CHANGES IT BACK

Posted by: @iancalderbank

↑

so, found time to get back to this now. my house is fully on the ASHP including DHW, and I've installed an ESP32 board to talk to the modbus controller in place of the ESP8266 I was using , just in case horsepower was an issue.

unfortunately, the behaviour is still exactly the same - when I change the value of the HA "number" for DHW target, I see the ESP get the change from HA, then a few seconds later the system changes it right back. I don't know where this change back is coming from. 

to those who have this working please, what am I doing wrong?

[17:14:15][D][number:012]: 'DHW Target Temperature': Sending state 55.000000
[17:14:16][D][modbus_controller.sensor:025]: Sensor new state: 711.00
[17:14:16][D][sensor:127]: 'DHW Temperature': Sending state 71.10000 ºC with 1 decimals of accuracy
[17:14:16][D][uart_debug:114]: <<< 01:03:08:00:00:00:01:02:26:02:C7:08:96
[17:14:16][D][uart_debug:114]: >>> 01:03:00:4E:00:02:A4:1C
[17:14:16][D][number:054]: 'DHW Target Temperature' - Setting number value
[17:14:16][D][number:113]:   New number value: 54.000000  <<<<< NEW VALUE COMES FROM HA
[17:14:16][D][modbus.number:061]: Updating register: connected Sensor=DHW Target Temperature start address=0x48 register count=1 new value=54.00 (val=540.00)
[17:14:16][D][number:012]: 'DHW Target Temperature': Sending state 54.000000
[17:14:16][D][uart_debug:114]: <<< 01:03:04:00:00:00:00:FA:33
[17:14:16][D][uart_debug:114]: >>> 01:03:00:57:00:01:35:DA
[17:14:16][D][modbus_controller.sensor:025]: Sensor new state: 0.00
[17:14:16][D][sensor:127]: 'Flow Rate': Sending state 0.00000 lpm with 1 decimals of accuracy
[17:14:16][D][uart_debug:114]: <<< 01:03:02:00:00:B8:44
[17:14:16][D][uart_debug:114]: >>> 01:06:00:4A:02:1C:A8:B5
[17:14:16][D][number:012]: 'DHW Target Temperature': Sending state 54.000000
[17:14:16][D][uart_debug:114]: <<< 01:06:00:4A:02:1C:A8:B5
[17:14:16][D][number:054]: 'DHW Target Temperature' - Setting number value
[17:14:16][D][number:113]:   New number value: 53.000000
[17:14:16][D][modbus.number:061]: Updating register: connected Sensor=DHW Target Temperature start address=0x48 register count=1 new value=53.00 (val=530.00)
[17:14:16][D][number:012]: 'DHW Target Temperature': Sending state 53.000000
[17:14:16][D][uart_debug:114]: >>> 01:06:00:4A:02:12:29:71
[17:14:16][D][number:012]: 'DHW Target Temperature': Sending state 53.000000 
[17:14:16][D][uart_debug:114]: <<< 01:06:00:4A:02:12:29:71
[17:14:25][D][uart_debug:114]: >>> 01:03:00:02:00:01:25:CA
[17:14:25][D][uart_debug:114]: <<< 01:03:02:00:00:B8:44
[17:14:25][D][uart_debug:114]: >>> 01:03:00:04:00:02:85:CA
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 0.00
[17:14:25][D][sensor:127]: 'Compressor Frequency': Sending state 0.00000 Hz with 0 decimals of accuracy
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 117.00
[17:14:25][D][sensor:127]: 'Outdoor Temperature': Sending state 11.70000 ºC with 1 decimals of accuracy
[17:14:25][D][uart_debug:114]: <<< 01:03:04:00:00:00:75:3B:D4
[17:14:25][D][uart_debug:114]: >>> 01:03:00:34:00:01:C5:C4
[17:14:25][D][uart_debug:114]: <<< 01:03:02:00:01:79:84
[17:14:25][D][uart_debug:114]: >>> 01:03:00:3A:00:01:A4:07
[17:14:25][D][modbus.number:023]: Number new state : 18.00
[17:14:25][D][number:012]: 'Target Indoor Temperature': Sending state 18.000000
[17:14:25][D][uart_debug:114]: <<< 01:03:02:00:B4:B8:33
[17:14:25][D][uart_debug:114]: >>> 01:03:00:41:00:02:94:1F
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 198.00
[17:14:25][D][sensor:127]: 'Return Temperature': Sending state 19.80000 ºC with 1 decimals of accuracy
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 201.00
[17:14:25][D][sensor:127]: 'Flow Temperature': Sending state 20.10000 ºC with 1 decimals of accuracy
[17:14:25][D][uart_debug:114]: <<< 01:03:04:00:C6:00:C9:DA:58
[17:14:25][D][uart_debug:114]: >>> 01:03:00:44:00:01:C4:1F
[17:14:25][D][modbus.number:023]: Number new state : 26.00
[17:14:25][D][number:012]: 'Target Flow Temperature': Sending state 26.000000
[17:14:25][D][uart_debug:114]: <<< 01:03:02:01:04:B8:17
[17:14:25][D][uart_debug:114]: >>> 01:03:00:48:00:04:C4:1F
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 0.00
[17:14:25][D][sensor:127]: 'DHW Status': Sending state 0.00000  with 0 decimals of accuracy
[17:14:25][D][modbus_controller.sensor:025]: Sensor new state: 1.00
[17:14:25][D][sensor:127]: 'DHW Mode': Sending state 1.00000  with 0 decimals of accuracy
[17:14:25][D][modbus.number:023]: Number new state : 55.00
[17:14:25][D][number:012]: 'DHW Target Temperature': Sending state 55.000000 << AND THE SYSTEM CHANGES IT BACK

It may be that your are writing to the output memory location for the DHW Target, which is continually being overwritten by the heat pump controller.

so, I did some more testing just now.

I'm using the same ESP config and ESP hw as steven and am unable to change the "DHW target" register 74 which he can change, using the exact same method. this should not be continually overwritten by any control algorithms in the HP's control. It's a human-only-changeable value that it maintains.

I've also temporarily set my system to fixed LWT mode to try to prove/disprove control of the heating side. (derek-m in this mode there is no WC. just the Target LWT on the HMI and only that).

I've proven beyond all doubt that register 68 (target LWT) is changed , with that change visible via modbus read, when the Target LWT is changed by pressing buttons on the HMI. When I write to 68 with my ESP, guess what, few seconds later it goes back to the value on the HMI. At post https://renewableheatinghub.co.uk/forums/postid/15483 TomC indicates he has control of LWT when the system is in that same fixed LWT a.k.a "Water Outlet" mode so this has to be possible. there are no samsung modbus values for controlling the WC upper or lower limits, so any working solutions for LWT contorl, can't be using those 'cos they don't exist. They must be using control of Target LWT, register 68.

I'm still stumped why this doesn't work, when my logical analysis of what others have done successfully, leaves me with no obvious missing pieces. At least one person has write control of registers with HA/ESPHOME "numbers". At least one person has Target LWT control working in with the beast in fixed LWT mode. So I will have to continue with elimination / experimentation approach . Given that here appear to be more people with some form of working control (3: william1066, redzer_irl and tom_c) using HA alone, rather than via an ESP (1, steven) -  I think -  my next step will be to get a modbus to USB adapter and try it directly from HA or perhaps directly from a laptop first.

Posted by: @iancalderbank

↑

my next step will be to get a modbus to USB adapter and try it directly...from a laptop first.

Different manufacturer I know, but this is what I did. My earlier HA/LAN trials (in more ways than one) primed me to expect trouble but in practice the wired modbus route is extremely easy to set up, and has so far proved very robust. It also makes it extremely easy to read/write to the heat pump using the python minimalmodbus module.

FWIW, I think targeting things that set from a controller are where you are most likely to be able to set values, because that is the way things are set up. For example, home owners won't like it if they set their DHW to be 50 degrees, and the heat pump over-writes it with something else. I think this is why I can use modbus to set the LWT for the weather curve, because it is something that is set by a human not the machine.

I also think turning off weather comp and using a human adjustable fixed LWT mode has potential. Following up on @scrchngwsl's ideas (in the other thread), I can't see why it shouldn't be possible to write code for any weather curve, and then use the output from as the input for setting the fixed LWT. A bog standard weather 'curve' is just a simple linear relationship between ambient temp and LWT. This could then be tweaked. For example, if there is solar gain, then solar adjusted LWT = weather curve LWT x 0.9 etc.    

Posted by: @cathoderay

↑

 

Different manufacturer I know, but this is what I did. My earlier HA/LAN trials (in more ways than one) primed me to expect trouble but in practice the wired modbus route is extremely easy to set up, and has so far proved very robust. It also makes it extremely easy to read/write to the heat pump using the python minimalmodbus module.

FWIW, I think targeting things that set from a controller are where you are most likely to be able to set values, because that is the way things are set up. For example, home owners won't like it if they set their DHW to be 50 degrees, and the heat pump over-writes it with something else. I think this is why I can use modbus to set the LWT for the weather curve, because it is something that is set by a human not the machine.

I think its just that the machines are different, your midea lets you change the weather curve via modbus. the samsung has no modbus variables for the weather comp numbers.

one of the people who has it working, can't remember who and not going to search the entire thread again, is able to write successfully to the "DHW target" temperature on samsung, and it has the desired / expected effect.  I just want to get to that same place. once I am there...land and expand.

Posted by: @cathoderay

↑

I also think turning off weather comp and using a human adjustable fixed LWT mode has potential. Following up on @scrchngwsl's ideas (in the other thread), I can't see why it shouldn't be possible to write code for any weather curve, and then use the output from as the input for setting the fixed LWT. A bog standard weather 'curve' is just a simple linear relationship between ambient temp and LWT. This could then be tweaked. For example, if there is solar gain, then solar adjusted LWT = weather curve LWT x 0.9 etc.    

exactly agree. replicate the machines WC curve in code, put the machine in fixed LWT mode , then set the LWT according to that curve. with tweaks up and down to that value for whatever  / however you want to optimise.

for instance I've noticed that , when I tell the heating to go from 18C to 21C at 0430 (and thus in practice, come on), the LWT always overshoots target by 3 or 4C then I get 3 or 4 cycles until it settles. same if its been off all day and has to come on from cold. would like instead to give it a "gradually increasing" LWT target for these situations to avoid the cycles. also for DHW mode (I believe this is a well known issue with samsung) the target LWT is immediately 55, which makes the compressor go flat out instantly, whereas enforcing a gradual ramp up of target LWT would probably achieve the same end much more efficiently (I believe some other manufacturers HP's have this)

Posted by: @iancalderbank

↑

I think its just that the machines are different, your midea lets you change the weather curve via modbus. the samsung has no modbus variables for the weather comp numbers.

I am sure they are different in detail, but I think the general principle that human settable parameters that are generally (ie write method - App, LAN, wired controller - is neither here nor there) writable should have some sort of modbus access. There is also the Homely example, presumably they have worked out how to set parameters in Samsung heat pumps, thereby establishing it can be done.

Finding the address of the Midea weather curve LWT was not straightforward. Here's the relevant page from the wired controller manual: 

There are some obvious typos (cooling when it should say heating), and you need to know the 'ninth curve' is the user settable weather comp curve, but armed with that, and the fact that T1SetH1 and T1SetH2 are Midea-speak for the left and right hand weather comp curve LWTs, then one can conclude the relevant addresses are 265 and 266. You may recall I tested a while back them and found they do work as expected (<=link).

All of which is to say it might be worth scouring through the Samsung literature again, looking for cryptic clues of writable addresses.

You could also try reading (not writing, what could possibly go wrong?) random unused addresses (easy to do via a python loop and minimalmodbus) and see if you strike gold. That's essentially what @derek-m and I did when I was using midea_ac_lan, but we didn't have much success, but we did find one or two undocumented parameters. With modbus, you should be able to test a much wider range of addresses.

Posted by: @cathoderay

↑

 There is also the Homely example, presumably they have worked out how to set parameters in Samsung heat pumps, thereby establishing it can be done.

exactly, homely have proven it can be done. and others in this thread have proven it can be done. I just need to prove by elimination / experiment, what is different about my h/w and s/w setup, until I find the thing I need to change.

Posted by: @cathoderay

↑

All of which is to say it might be worth scouring through the Samsung literature again, looking for cryptic clues of writable addresses.

I read that manual almost every day 🙁