my understanding from reading the manuals is that when water law is active - you cannot select "indoor" mode on that screen. 

if indoor is active you are telling the heat pump to adjust it's temperature based on the indoor thermostat rather than the outdoor weather

*as far as i understand it!*

@simonh I think I know what’s happening. I have water law enabled but the room temperature is controlled via the Samsung controller which is acting as a limiter at 22C. When it was mild it was turning off the HP before it started cycling now it rarely turns off the heat pump at all as the WC is limiting the room temperature.

@simonh I stumbled across this which relevant 

https://community.openenergymonitor.org/t/i-want-to-punch-my-samsung-controller-fsv-2091/27143

Posted by: @simonh

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my understanding from reading the manuals is that when water law is active - you cannot select "indoor" mode on that screen. 

 

if indoor is active you are telling the heat pump to adjust it's temperature based on the indoor thermostat rather than the outdoor weather

 

*as far as i understand it!*

There are 2 main display options on your wired remote controller. In both displays the current flow temperature and room temperature are shown on the right hand side. On the left hand side of the display is a setting that you can adjust with the up and down arrow.

• If you are using an external thermostat (FSV 2091/2092 = 1-4), then the adjustable setting is the Offset that you can apply to your water law settings (+/- 5C)

• If you are using the internal Samsung thermostat in the wired remote controller (FSV 2091/2092 = 0 (Not use)), then the adjustable setting is the desired room temperature.

In both cases, the flow temperature is controlled by your water law settings ie weather compensation is in operation. You could argue that using an external thermostat is more versatile as not only can you set the desired room temperature limit, but you can also change the target flow temperature without going into service mode by simply changing the offset value. Whatever you choose, weather compensation will be operating.

There is another option - in service mode --> Indoor Zone Option --> Standard Temperature --> Water Outlet. This allows you to set the desired flow temperature directly and in this case there is no weather compensation. This isn't used much.

@mike-h Thanks for that clear explanation Mike. Very useful.

@mike-h what I don't understand about this setback control is... How do I tell it when to operate the setback? 

Or is Samsung basically saying that it's a manual thing for whenever you change it and then change it back? 

But that would be ridiculous to do every night! 

I have water law set up (auto), but when I try to schedule, the only options I have are dhw and holiday. Daily and weekly options aren't available...

Richdorm

@richdorm do you have an external thermostat, or not? In other words, which of the two modes @mike-h highlighted above are you running in?

We use a programmable room thermostat (first example in @mike-h post above), and simply knock back the desired room temp to 18C overnight, or we can programme it between set hours.

If you don't have an external thermostat, then I think you need to set a 'Weekly' schedule. Are you able to do this, or is 'Weekly' greyed out?

Posted by: @richdorm

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Or is Samsung basically saying that it's a manual thing for whenever you change it and then change it back? 

But that would be ridiculous to do every night! 

Exactly that so far as I can tell from the manual and discussions with the Samsung rep at the installer show 2025 (I don't have a Samsung).

Samsung doesn't give an option to have a flow temperature setback or set forward unless you use an external controller.  The only way to achieve setback or set forward using the Samsung controller is to operate it in temperature sensor control mode, which you can do as an overlay to WC.  There is no way to do it if you want to do it on pure WC. 

I challenged the rep at the last installer show about this, he was keen to show me the new flashy full colour UI, which still doesn't do this.  His colleague then admitted that the flashy UI uses the same underlying logic and so hasn't expanded the capabilities to do this very useful thing.  I confess that I told them at this point that their controller was one of the worst on the market of the major manufacturers, which they didn't entirely warm to (but didn't actually attempt to deny).

IMHO this limitation is rubbish.  It's not unique to Samsung though.  If you want to do this sort of thing with Samsung or other heat pumps that have this limitation, you need homely or to write your own script in HA or similar.

@jamespa or havenwise perhaps?

Posted by: @richdorm

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@jamespa or havenwise perhaps?

Yes, and probably also Adia although the latter has a much greater scope

@old_scientist so - I have a Hive thermostat, which I've currently got set to 25 (!) so that I could set up the water law without it interfering.
I guess having the hive means I've got an "external thermostat" then?

So once I've set up my water law (which I've more or less done) then I could schedule the hive to be (say) 2C cooler at night than the desired 19C - which would have the effect of limiting the pump.  Is this correct?  Most people say "don't use a hive!"

Posted by: @richdorm

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So once I've set up my water law (which I've more or less done) then I could schedule the hive to be (say) 2C cooler at night than the desired 19C - which would have the effect of limiting the pump.  Is this correct?  Most people say "don't use a hive!"

Not really in the way you describe

The effect at best would be to switch it off altogether until the house cools.  It wont limit it by reducing FT, which is what you really want to do.  However I think Hive may do 'pulse width modulation' on its output, a crude way to control on on/off boilers 'proportionately'.    If it does this (several smart thermostats do) then its a real no-no for heat pumps.   You would need to check this before even considering using Hive this way.  Its possible that this function can be disabled but you would need to check with Hive or someone who is an expert in Hive. 

The Hive guy at InstallerShow definitely told me that they had looked at making Hive properly suitable for heat pumps but had not pursued it because there was no standard interface.  I take that as an admission that currently it isn't!

Samsung has an on/off schedule function inbuilt I believe; use this if you want to switch the heat pump off for a period and leave the Hive doing nothing!

Unfortunately this is where the crudeness of Samsung's controls bites a bit.  That said, although my Vaillant is cleverer in this respect, I still dont bother with a nightime setback, I just have the bedrooms at a slightly lower temp permanently.

PS  There is something here about what Hive does.  The 'time proportional' element is the one which may be problematic, depending on how its actually implemented, which I doubt is publicly documented.