I too have a problem with the heat pump Samsung AE160MXTPGH + AE260TNWTEH from the beginning, since it was installed a few months ago.
COP is always around 1.2-1.8, rarely above 2.
I called the Samsung authorized service center, but so far they haven’t been able to solve the problem either. The assumption is that the problem could be in the time of HP operation - it always works from 21-24 hours.
The configuration of the system is such that between the HP and the consumer we have a buffer tank of 100 liters, and behind the tank is a secondary pump for one circuit of floor heating. The secondary pump is electrically connected to the indoor unit of the heat pump.
The problem is that the HP turns on constantly, as soon as the temperature in the tank drops by 1°C (maybe even less). It is set so that dT should be 5°C, but this does not happen.
Lately, I have turned off the floor heating in most of the house because we are heating the space on the fireplace. 2 hallways and bathrooms, as well as the bedroom, are heated. But it consumes very little heat from the tank. dT on the flow/return of the secondary side is very small, around 1-2°C. This means that the heat pump would not have to work all the time to replace the energy consumed.
Samsung advises that we connect the circulation pump via the floor heating control cabinet, and decrease temperature in bathrooms. But since I want my bathroom floor to be warm all the time (and also air in bathroom at 24°C), it doesn’t seem logical to me to turn off the circulation pump because the floor will get cold. It would be much better if the HP was turned off and turned on only when the temperature in the tank (or flow/return) drops below 5°C.
Does anyone know what could be the solution?
Btw. during installation, Samsung advised us not to install tank temperature sensors. They said that the regulation will take place only through the flow/return sensor in the HP itself. And I’m not so sure if this is good option? Since, if HP not operating, how will it know that temperature in tank was dropped by 5°C?
I have total excel report of COP and all temperatures, also power consumptions from the beginning, but cannot upload since I’m new user here…
Flow temperature is set on 35°C, all the time, outside temperatures varies between -10 and +15, but seems that does not affect much on COP of the HP.
I have only wall controler by samsung WR-WW10N
It seems that it turns on by supply temperature sensor inside HP.
I’m in contact with Samsung distributer in my country, and they send official service team, but it seems that they are also confused… They have send the issue questions to Samsung in Netherland I think, so now I’m on hold until they answer.
I only checking on HP wall unit WR-WW10N. But according to main electrical meter of the house, it seems that it’s really consuming that much kWh.
It is really enough warm inside house… We had a few days period when it was -10°C at night, and about +5°at day, but it was enough heat with flow temperature of 35°C. Daily consumption you can see in excel per each day, together with outside temperatures and flow temperature.
thats the ones I wanted. in the mode you have it will try to keep the outlet water temperature very close to the value set. it just needs to be off for a few minutes for the outside air to cool the sensor, then it fires up again. So it’ll be going on and off very frequently. really bad short cycles which are always going to be inefficient. nothing else tells it to be on or off.
this is the second person in a week with the system in this mode, I don’t honestly know what the real world application of this mode is.
what I would suggest to do is
set the controller so that it becomes the thermostat for the house
service mode->indoor unit options->standard temperature->indoor
expect to get some error messages when you change this but if you press off->on on the controller it’ll sort itself out.
2 set the water law (weather compensation) FSV values so that it runs at the water temperature that you want for your house.
there may be other issues in your system as well : buffer tanks add complexity and reduce efficiency, and you have a big heat pump so I hope you have a lot of emitters and a big lossy house. But this needs changing first.
once this is done you’ll need to re-open the emitters that you closed down. otherwise you have not enough emitters in circuit so it will cycle.
You think would be better for efficiency to avoid secundary circulation pump, and connect heat circle directly on circulation pump from HP? It have enough flow and pump head (UPMM25-9.5 Grundfos)… In this case, the return could be connected on higher connector of 100lit. buffer. … something like on picture:
yes, that 2nd diagram shows what is generally accepted to be the more efficient way. still use your buffer tank but only 2 pipes , 1 in 1 out, so its functions as whats usually called a “volumiser”. only 1 circulating pump needed then and you have the option to run it as variable speed (UPMM can do this, its exactly what I have ).
On January 18th (coldest day of the year in UK, around -2°C), these systems produced 120-140 kWh of heat over 24 hours (average power = 5-6 kW).
Your system is producing half as much heat in a colder climate of 1.5° and yet your house is warm enough? So either your insulation is more than twice as effective as any of these properties, or the Samsung unit is massively underestimating the heat it is producing. This could explain why COP appears to be so poor, and may not be as bad than you think.
I would suggest finding the temperature sensors, and check that they are securely fitted to the pipes and covered in insulation.
The calculated yearly heat loss for house (Qhnd) is only 8278kWh/year, or 43,3kWh/m2 year. This calculation is to heat the house on 20°C, but we are heating it at least on 23°C so this kWh/year will be increased, supposed atleast 20%.
Peak hourly heat loss at outside temp -15°C is 10,3kW.
Insulation on the house is 20cm on walls and 20cm on flat roof. Windows are also quite good insulated- U=1,1W/m2K.
Temperature sensors are inside of HP (i think) so I don’t have approach to them. Authorized service team was here few day ago, so I suppose they checked all sensors since this was their first assumption.
Take in consider that from 6th of January till today we are heating at least 80m2 with fire place, so heat pump is only covering 110m2. Since HP was using to much electricity, we decided to heat with other heat source :-)…
This could actually work, but I don’t think this is the best possible solution? Because then I have to drive whole system as per one single room where is inner thermostat (which is living room). So when there will be enough warm, all other rooms will not be heated (bathrooms will not have warm floor or warm radiator, hallway will not be heated… living room have lots of sun through big glass surface so it will be actually warm enough through day withouth additional heating.
I was hoping to have some solution that we use buffer tank and that temperature in buffer tank turn on or off HP regarding temperature inside tank? Like:
flow is set on 40°C
temperature in tank below 35 - HP goes ON
temperature in tank 40 - HP goes OFF, and will stay off until reaches 35…
circulation pump is always on
Now it always try to fill till 40 even if it drop only by 1 °C
I think this would be much much better solution. Not sure if Samsung is able to do this…
the way you are (were? did you change it) running it is not monitoring the buffer tank. thats not where the sensor is. The sensor is in the outdoor unit. when the outdoor unit is off, the water temp in the unit drops (its outside!) quite quickly by 1C , then it comes back on again to increase it by 1C . which takes a very short time, because its looping through a buffer thats already warm… you will be getting very short cycles repeatedly, that will be why your performance is awful and its seeming to be on all the time.
yes you will have to run the whole system as one room. that is what most people with heat pumps do. In my house I removed all TRV’s (except bedrooms) and I keep almost all doors open. Balance the radiators so that heat is even. Its a big mindset change.
the other idea you are talking about . Speculating: I guess you could to put a sensor in the buffer and wire that as an external thermostat to the heat pump. you’d still need a means of triggering to run the secondary pump as that’d now be independent of the primary side - and that would be usually a thermostat in the living space. so kind of back where you started. unless you had multi-room sensors and put through additional logic to determine secondary side run/no run. How this would all behave in terms of efficiency and performance I don’t know. Its not one of the designs that samsung puts in their documentation and I suspect you’re going outside the experience of most of the people on this forum. certainly me. note, I am not a heating engineer just a user who installed his own heat pump according to the single loop best practice, so when I said “speculating” , I did mean just that. I suggest to consult a professional heating engineer if you want to go down this route (unless someone else on here knows, in which case I defer to them).
@Timbones the sensor for the WT is in the outdoor unit, people have talked about insulating over them and the values not being 100% accurate compared to heat meters , but I find on my samsung its value is about right, compared to that of a temperature sensor on the primary pipe inside to the house, so I don’t think sensor value is the issue in darko’s system. I think its what I put in the 1st para above. Also, its probably an oversized HP as well so once the “constantly maintaining WT” is removed from the equation then short cycling for the usual reasons is likely to appear as well.
I switched to water law, but when I switch to Indoor regulation (zone regulation according to room temperature), then Auto (for selecting water law) is grayed out.
It offers me Auto (or water law) to choose only when the regulation is per supply temp… Do you have any suggestion what to change?
Here is pic:
Ofc… we all are speculating. Professional heating engineer (HVAC designer) does also not know for sure, because this is something that must be checked by Samsung engineers who are deeply familiar with all possibilities of their product… We are checking this with them, so I will give you update soon as I have some new info from their side.
But this one room regulation is a big step back if this is only way of temperature regulation to get some higher COP. There is so much more logical way, but only thing is if Samsung logic is possible to accept this.
Also water law will not (most probably) resolve my COP problem. Probably will be less energy production and consumption, but I believe that COP will not be much changed. Will see what happens
Not sure why on other heat pumps they have good COP, but mine is so poor… There must be some special issue…
with the change of settings, the screen unit is now acting as a thermostat to determine whether to run or not. by doing that you will avoid it running all the time (if your house is up to temperature, obviously!). you have 23.5 so that seems more than hot enough for me!
the heat pump is still using water law to determine what temperature to run at when running. the water law value will be as per the FSV’s 201x and 202x
as marko says, samsung controls aren’t sophisticated. if you can get it it matched to your system and tuned nicely though they are enough to get a good COP.
something like Homely or a Planet Devices might benefit you, to analyse your system over modbus.
I believe your issue over the last weeks has been horrible short cycling due to keeping a constant WT.