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E121 error code on Samsung 12kw gen 6
I've had this error pop up after changing back from a flow temp only setting to a WC setting.Â
The fitting manual tells me to check PCB connector CN41 and it would appear nothing is plugged in there.Â
I've found videos of older Samsung units and it's a setting in the menu telling it to check but as there is no sensor it comes back as open circuit. It appears this might be what is happening with mine but I can't find the settings to turn it off. Can someone tell me how please?Â
I also appear to have an issue with the Teva out sensor as that is reading -50. Not sure if the two are connected. ThanksÂ
Â
Hi Craig,
When you changed to fixed LWT, I believe that you also changed the setting for the External Room Thermostat, 2091 or 2092.
I suggest that you check the settings and put them back to their original values.
When changing settings always keep a record.
Â
I did change these, but these settings are all back to what they were originally. I take photos on my phone of all settings before and after. That way they are date stamped too so I can go and check a particular day.Â
The part that I have changed that I believe is correct is Indoor Zone Option, standard temperature. I've changed this to indoor and not water outlet.Â
When changing this from Water Outlet to indoor, that is when I get the error.Â
@craig1980 It should be set on Water Outlet if you are using an external thermostat. If you are using the wired remote controller as your thermostat (the one in your airing cupboard), then you set it to indoor, but I believe when you do that there is an additional step required, quite what I don't know! Possibly FSV 2092 or 2093
Posted by: @craig1980I did change these, but these settings are all back to what they were originally. I take photos on my phone of all settings before and after. That way they are date stamped too so I can go and check a particular day.Â
The part that I have changed that I believe is correct is Indoor Zone Option, standard temperature. I've changed this to indoor and not water outlet.Â
When changing this from Water Outlet to indoor, that is when I get the error.Â
Hi Craig,
Is your system working? What are the present settings of #2091, #2092 and #2093?
Â
@mike-h I'd be happy to run it on the wired controller rather than external stats. I'm led to believe that's how they like to run. I'm not using room stats as on/off but as a back stop to WC to stop it going too warm.
@derek-m yes, system is working, still doing 20 secs - 8 min thing though. When the error shows is when you change "standard temperature" from water outlet to indoor. Although Mike has pointed out that it should be set on Water Outlet with my current set up using room stats.
As for #2091,2 and 3 they are all set on "Room temp. On/off or WL interlink on/off (water pump 3).Â
Hi Craig,
I have been giving the page from the manual that you posted, a closer inspection, and although, in typical Samsung fashion, the text is about as clear as mud, the diagrams throw a little more light on the subject.
The first diagram #2092 2 would indicate that when #2092 is set to the value 2, the heat pump will stop when the LWT achieves the value set by the WC curve (WL), but the water pump should continue to run for a further 1 minute.
When #2092 is set to the value 3, the water pump continues to run after the heat pump has stopped, the on - off of the water pump possibly controlled by the thermostat, but that is not specified.
When #2092 is set to the value 4, when the heat pump stops, the water pump should run for a further 3 minutes, then the water pump is stopped for 7 minutes, then runs for a further 3 minutes ad infinitum, until the heat pump restarts.
This seems to tie in to some extent to the way your system is stopping and starting.
The manual does not clearly state the value to which #2091 or #2093 should be set, so you may have to try different combinations.
I would suggest that you try changing #2092 to the value 2, and possibly also #2091. Then try the value 3 and then value 4, noting the operation each time.
Â
@derek-m I've now set 2091, 2 and 3 to Room temp. On/off or WL interlink on/off (water pump 2).
Am I right to assume this is value 2? I'm not sure how to tell which is value 1, 2, 3 and 4
As far as I am aware, you go into Field Setting Mode, as you did when you obtained the data previously.
Â
@derek-m yeah, I'm in field settings in 2091 but there are 5 choices that you can scroll through.Â
Not use
Use signal only on/off
Use (signal on/off) or WL interlink off (water pump 1)
Use (signal on/off) or WL interlink off (water pump 2)
Use (signal on/off) or WL interlink off (water pump 3)
I wasn't sure which of these was which value 1-4. I'm guessing not use is 0 and the others are the corresponding numbers so pump 2 would be value 3.Â
Â
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