I’ve found one unpleasant feature of this heat pump. This is information which might be interesting for people without DHW heating - TURN OFF physically your pump outside winter season when you don’t need to heat the house because this pump is consuming ~1kWh/day electricity in idle.
Here’s my chart. You can see that every couple of hours the pump is idle, the pump powers some internal heating elements to keep oil level on temp - or something like that but it’s around 50W. It’s interesting to see that it is doing even there is +20C outside. I thought it was needed only for lower temperatures but nope, it’s all the time.
So because of this behavior the pump effectively lowers the daily COP almost by 1. Water heating I had almost 3 and because of this I’ve finished the day near 2. Also you can see once the pump run the circulation pump for some reason at 16 o’clock. That’s sad to watch. So if you heat let’s say 6 months in a year then you are idle for another 6 months and if the pump is not turned off by hardware switch (this I need to confirm if it consumes this power also in case both DHW and space heating are off) then you will waste 180kWh of electricity yearly for nothing…
There is a chance if both DHW and space heating is turned off then maybe it won’t take this extra power for internal heating of outdoor unit components but this must be checked. I’m doing it right now so I will update later…
UPDATE:
So HP is consuming power even if both DHW and space heating is turned off so definitely those who does not use DHW heating turn off the pump by circuit breaker outside winter!
That’s very interesting but is it not the compressor crankcase heater that all modern heat pumps have? It may modulate its wattage at higher ambients over time.
Refrigerant naturally migrates to the coldest location on a system, which is the compressor when the temperature is cold and the system isn’t running. If you start a cold compressor full of refrigerant, the oil will turn to foam and lose lubricating properties.
If you turn it off at the isolator and not use the heat pump outside the heating season then maybe it will be OK but the humidity and temperatures changes like we get in the UK season will risk deterioration of circuit boards etc. In any case you would need to remember to have the unit powered for 24 hours before the first operation of the compressor to avoid foaming and premature wear.
I have been advised to always leave the heat pump and controller powered during the summer season but I am fortunate to have plenty of excess stored solar power to use. What do others do?
I think this is exactly this what you have described. I’ve noticed that during time the consumption is higher the IPM1 Temperature is raising as well. I guess it’s internal heating of compressor oil to the temperature.
This is a day where pump was completely standby for the whole day. No DHW or space heating. It has consumed around 1kWh of electricity. 265W is normal standby consumption so it means it took 735W for oil heating.
Yeah, it’s not that bad at the end but anyway users who does not have DHW this is useless consumption outside of winter season. I swear I saw R290 pump not doing this so probably it is specific only to R32 version.
I agree to this, honestly last winter I’ve turned it on just after switching isolator so most people are not aware of this. Seems no harm done but one never knows. I would think the pump has algorithm to heat oil first before it starts compressor but not sure.
Yes, could be but then probably it has different compressor. I saw monitoring of one R290 and it was not doing it either. So again some specialty of this crap HP…
I have been very pleased after a year of running with the Samsung HT. This is a more complex two stage compressor. Each day it runs up to 68 C to heat my existing DHW and up to 50C as necessary for on my existing radiator system with an acceptable efficiency.
If you do not need an high temperature heat pump as a direct replacement for fossil fuel boilers then it may not be for you, but it is working exceptionally well for my application.
Well I don’t care much about DHW to be honest. This is only a tip of the iceberg.
First Samsung falsely claimed this is 8kW unit. It is not. It is 14kW unit crimpled by the software. Ridiculous. This of course cause me issues in warmer climate. I would never buy this if it’s stated clearly.
Then modulation is very bad, power spikes all the time, this is not like a inverter should work. My 2x AC units has super smooth modulation which can’t be told about this Samsung.
Third DHW heat stealing. When I did not have DHW no problem. For anti - freeze cycles it just run a pump for 5 minutes so water in pipes has been mixed. All fine. After I added DHW it steals the water from the DHW tanks which causes 2 degree temperature drop in a tank. If it run AF cycles 5x during a night (I have pump of from midnight to 6a.m.) It takes 10C from water and I can start reheat again.
This pump despite it is HT is not able to heat water to more than 55C without additional heater. Why.
Pump takes about 1kW daily in idle. Does it really needs to reheat the compressor if there is 20C outside ? Why other pumps not doing this ? Never seen such behavior on my air conditioning units.
And there are also other things which makes me crazy but it’s good you are satisfied with it. To me the pump is dumb like shit and not satisfied at all but have to live it it until it breaks.
Yes I do understand your points. The reason I chose it was only because it was recommended as a direct replacement for an oil fired boiler. It does not seem to exhibit these faults when used like this. It does only modulate to 900W input I have set backs during the day that turns the pump off during mild weather. The DHW heat leak for frost protection is not a problem for bottom mounted tank coils of course.
I would agree with you that the advertising is not clear that this model is designed as a more sophisticated unit that can achieve direct replacement status for fossil fuel systems running at DT50 radiator temperatures that are common in UK. If you do not need this feature or are starting from scratch with emitters then there are other lower cost heat pumps available from Samsung without these foibles.
Yes, exactly. I think for your house it can be fine because obviously you can utilize higher power but for my house and system it’s a bit overkill. I would need something which can modulate to 400W at least.
Why for bottom mounted coils is not a problem ? Truth is I have vertical running across whole tank height so this steal pretty much from it. Still why there is not a stupid setting in configuration where user can choose which circuit to use for AF protection ?
You are right that any cheap HP would do this for me maybe better but didn’t know that time sadly. Thought I’m buying 8kW HP which normally should be able to modulate pretty low. Look at R290 gen. 7 pumps. Their compressors are really declared size and not this BS that 8kW is 14kW crimpled. Very upset on Samsug for this. As I’ve heard its not just a Samsung but practice of some others manufacturers. Why they don’t state minimal power draw ? This could help a lot…
The bottom mounted DHW coil is always in the colder part of the tank so if it used to take heat from the house for frost protection it will not cool all of the DHW tank - agreed there should be software options to change this
This HP is much greater capacity than 8kW nameplate implies and I think this is a confusion of the rating for HT pumps. If you look at the performance table unlike normal 8kW heat pumps that start to reduce output in negative outdoor temperatures it remains at up to 8kW and not reducing to 5kW output as is more typical so there is a fall back situation to keep the house warm (albeit at a cost by using high flow temperatures). The high temperature operation output can be up to 11kW with 4kW consumption. This rating of two stage heat pumps is discussed elsewhere in the forum. So it is not a typically rated 8kW more like a 11kW.
Why it is advertised at 8kW? I do not know. Maybe it is for certain market requirements where keeping below the maximum load rating is important.
The same goes for the software changes. I do not know why the Samsung HT is like this but it may be due to protection of the safety systems running at up to 70C which you do not need.
Maybe you can get an exchange from your distributor for a Samsung without HTQ which are significantly cheaper, the controller would still be compatible and it would not have these problems for your installation?
The world of domestic heat pumps seems to be developing fast especially for retrofit programmes, what I have today will probably be outdated in five years. It is all just an experiment but working out so far…fingers crossed!
Thanks. It’s not as bad as it seems but some nuances irritates me pretty much I know that 99% users don’t care and the only thing they consider is COP but sometimes I wish this pump thinks more. Guess we need to wait until AI is integrated in pumps as well so you only tell it what to do and it will do it
Problem is that this range of R32 all uses same 14kW compressor and 8kW unit has only smaller HE and fan. That’s the only difference lol. I did lot of research and knew pretty much I don’t want a pump bigger than 8kW just because of modulation and here I go, stayed with 14kW unit lol.
I have COP around 3 which is not that bad at the end if we consider my system but anyway
I only regret I didn’t wait for R290, this would suit me much better I guess but that’s life. At least the pump is really quiet and this was one request I had that time.
It’s too late to replace it but nah, I can live with that Cheers.
I know that 99% users don’t care and the only thing they consider is COP but sometimes I wish this pump thinks more. Guess we need to wait until AI is integrated in pumps as well so you only tell it what to do and it will do it