3rd party thermostat Samsung gen 7....easy question!

Hardware Heatpump
1

I’m using the thermostat in the controller as a high point switch but the recent colder weather has reminded me to install a third party stat I have in stock instead. I asked Samsung earlier this year and got these instructions below.

Question is they refer to live and switched live, I was expecting zero volts contacts, if someone has fitted one is it really switching live as in mains 230v?

Thanks

If you wanted to utilise a 3rd party thermostat instead this would need to be hard wired back to the heat pump.

Terminals B19 – Neutral

B20 Live

B22 Switch live for call to heat

You would also need to reconfigure some parameters in the service menu.

In field settings, FSV 2091 will need to be set to “use signal only on / off”.

In indoor zone option, standard temperature will need setting to “water outlet”

2

Hi, yes the advice from Samsung is correct. That is how my 3rd party thermostat is wired, although I no longer use it. I find the thermostat in the wired remote controller more useful. Note that you can only use one or the other, so I am not sure why you wish to rewire your 3rd party thermostat.

3

Hi, Yes it’s interesting that you prefer the controller thermostat……It’s the 2 degrees hysteresis I find awkward. I only use it as a top switch off limit as its in the right temperate spot for it but dropping 2 degrees to come on again is a bit much for us.

Reason I ask about 230v is as I’ve capacity in a data cable but if its 230v I’m switching it becomes a bit more difficult and a dedicated cable.

4

My hysteresis is 1 degC. I know some find even that too much. Are you sure yours is 2 degC?

5

Got this reply from Samsung technical Jan 3rd this year, also just tried again in case I got it wrong…..you never know! .Actual temp 21.7, set to 22 on, set to 20.5 still on, set to 20, still on, set to 19.5 off

The logic in the control is 2 degrees over set point to go thermo off. This is built into the controller for when it is used as a stat and cannot be changed.

There is new firmware to be released shortly (no date has been confirmed yet) that has a plus 1 degree thermos off instead of the 2 degrees currently.

Hysteresis that will be changeable is based on the thermo on control not the thermo off.

6

Just got reply from Samsung saying that there is an update available to change the hysteresis to 1degree so dont need to anything.

7

I am quite surprised about the information that you have had from Samsung and your own experience. My hysteresis is definitely 1°C and others have confirmed this - see link to post below. Like Glyn, I have a Gen 6 Samsung, so perhaps it is different for the Gen 7s.

8

Thanks for the info, looks like they probably went to 2 degrees with the Gen7 but at least now its going to something more sensible with the update.

9

Update, update. How is it installed? Over air - or wishfull thinking?

10

Neither, its a site visit with an engineer to update the software, got it booked in a couple of weeks so see how it goes.

11

@JPB

I don’t know if it will be more suitable for you, but Samsung makes a separate thermostat which can be located in a different location to their wired controller. It is then also possible to disable the thermostat in the wired controller so this separate thermostat is the one that controls things. I believe it is also possible to add one of these separate thermostats to control a second zone.

The Samsung part number is MRW-TA.

Some posters in these forums have mentioned it. However it seems a lot of people instead use the 3rd party Homely controller and its thermostat which is inherently separate to the controller.

Homley state that they do not support two thermostats although I did not ask them about running two zones.