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Is it crucial to get flow temperatures with heat pumps right?
Hi Patrick
In a word yes. If you want an efficient heat pump system then you need to set the flow temperature as low as possible while still providing a comfortable house.
You need to set up Water Law in your Samsung controller. Do you have any idea how it is set up at the moment?
I have a Samsung so should be able to help.
Mark
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
5kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
I will have a look at some downloads and see if I can spot some instructions thank you!
@alfapat this shows how https://m.youtube.com/watch?v=FcXAtVjdRE8
I have a feeling though that he puts one of the figures in the wrong way around in the video though
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
5kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
That is an older controller you have so the procedure might be different unfortunately
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
5kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
so been to the 20 settings and I set 2011 to -5c , 2012 +15 weather comp, 2021 @50c, 2022 @ 32c going by gen6 vid above.2091 @1 . The only one corrected is 32 degrees c. That being the change I have put in , will that make adiffence do you think?
I will update my system if I knew how to do it , interestingly I am considering a solar/battery installation as well.
Here are my settings, I think the 201 settings in the video might be backwards. You can always check by feeling if your radiators are hotter in colder weather. I would try and get the flow temperature as low as possible, 50C particularly will be expensive. Just lower them gradually by a degree a day and see how it feels. If you get to 45C when its -5C outside and the room is too cool. then raise it by one and you have it. Same when the weather is warm.
Solar panels are always a good idea, batteries a little more nuanced as they are expensive. If you have an EV then you can access very cheap overnight tariffs to fill a battery.
Have a look at my blog which should give you a few ideas 🙂
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
5kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
So 2021 setting You reckon that the rads circ.@50 might be too high. It would be difficult to measure apart from laying a thermometer on it I suppose. If the Room temps are still reaching 22 , which its set for just now , incidently the room the thermostat it is in just now is still only 21.5 and should be 22 since 15.1 hrs , it takes a while ? At 2.0 degrees lower , I can try that to see if its easier to reach that tomorrow . Am I looking at the right path here, please.
Blog? Sorry where and how do you put thar stuff below about your system please.
@alfapat So the absolute flow temperature isnt important. Just how it makes the room feel. If its been 15 hours and you still havent made the desired room temperature, thats an indication that you may need to increase flow temperature in the water law settings.
The problem is that high flow temperatures lead to inefficient operation, so you need to try and keep them as low as possible. If you find that you need a flow temperature of 50C when its cold, then the only thing you can do is improve the insulation of the house or fit bigger radiators.
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
5kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
@bontwoody Ah , ok I get it now. Thank you . No it’s only 5 hours thankfully. But it’s still a while @ 1 degree from 21 to 22 degrees. I’ll try it lower and see if I get grumbles ! ☺️ I can check energy hub also .
It is after all said and done -4 just now , and the bungalow has pretty decent insulation including underfloor, roof but because it’s timber built on dwarf the outside plaster has a thin polystyrene coat . Airsource installed on energy trust grant approval 8 yrs ago
Ah I see where you get 15hrs , no its 15.00hrs , (3pm)
Very cold yesterday but the system did cope , total of 114.68kwh £28.05.Trying to match heat pump with Octopus cosy they have three lower tariff slots and only got to grips with adjusting them yesterday after three days on new tariff. I will give this another day and drop down the flow temp to 48c.
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Are they crucial to get it right?
How do I know what the flow temperature should be and is it adjustable,
I have virtually no one locally that is able to help me run this system (Samsung 16 kW) as the installers went into liquidation and it been a nightmare getting the system running efficiently as far as I am able.