21

Hi Rachel, I’ve not yet done an episode on the BetaTalk about UKAS cert bodies. Would you be against being a guest?

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22

Hi Nathan & Rachel,

Could I intervene in your conversation about UKAS, MCS , NIC EIC and the RECC.

My experience with the NIC and the RECC was initially favourable over a five month “investigation” period.

The NIC and RECC completed their “investigations” , handing over to the MCS .

The MCS, declaring itself “a private Charity” then handed my now “complaint” to UKAS.

UKAS then declared that it , UKAS, was "not a regulatory body " and “could not intervene”.

A seven month pyramid of buck passing between “private Regulatory Charities”

ian

1 Like
23

Hi William ,

I just wanted to show a picture of “Sammy” , my pet Heat Pump with his volumising tank.

I am now in fuel poverty and hypothermia throughout Dec 2022 thanks to the Heat Pump.

Sammy_with_Tank_2
Sammy_with_Tank_2768×1024 116 KB

Sammy_1
Sammy_1768×1024 108 KB

Notice the triple expansion vessels and the complex tangle of pipes!

James Watt would be ecstatic about the fetching Copper and Brass on show!

I will need to fit a Backup boiler , my original Gas boiler having been removed by my “installer”.

ian

24

Blimey!

That is unbelievable and the heat loss from the tank/pipes will be huge as nothing is insulated. In the summer that will cause significant overheating. At least it appears to be in a ‘heated space’.

25

HI Brian,

I would insulate all pipework related to hot water (including pipes to and from the heat pump which will have a dual use), but once you get to pipe work that will only ever transport central heating water, you can probably leave that not insulated unless you are getting too much heat into an area from the pipes, or the pipes pass through spaces not part of the house proper (i.e. outside the insulated envelope of the house)

William

26

Hi Ian

Thanks for sharing the photos and these details.

Efficiency will be the highest with the lowest flow temperature and delta t that is possible for the combination of your heat load and your heat emitters. I don’t have enough experience to provide anything near a silver bullet here.

As far as i know fans to your radiators could increase radiator output up to 1.8x depending on what radiators you have. But I am not sure how much this would reduce the flow temperature and what savings can be realised from that or even if it is practical in your case.

Other than continuing to get redress from the installer by comparing what was promised vs what was delivered, I am pretty much out of ideas otherwise.

William

.

27

Hi Ian,

Doing some maths with the data on Page 28 and 29 of the following document together with the assessment data from your “installer” should give you an idea of what is possible, though there are quite a lot of variables here, so this is a non trivial exercise.

Ultimately what is possible is limited by the laws of science.

https://www.climamarket.bg/wp-content/uploads/TDB-EHS-Tank-integrated-hydro-unit-for-Europe-Mono-R32-50Hz-HP-Ver.1.1_190522.pdf

I have noticed my COP drop significantly when I added hot water to the heat pumps responsibilities, though this could be outside temperature etc as well. But looking at the right hand side of the charts, shows that your hot water demand will be a factor in efficiency. So insulating appropriate pipes, as Brian suggested is probably a good option.

William

28

I see you chose hypothermia rather than the huge electricity bill!

I’m near Rochester in Kent and had been running nicely in October/November with effectively similar values to yours and really good CoPs, but when it snowed I chose comfort over cost.
I eventually reverted to the recommended (by Freedom Heatpumps for southern/English? homes with radiators) 15/-2, 37/50.

Over the 10 days December 9-18 when we had sub-zero temperatures, we averaged £25/day with one day a few pence short of £30.
After the snow cleared our average returned to about £10/day.
These £ figures include all electricity use by the house & pond, we have loads of solar PV not producing much at the time and a 12kWh battery which is filled to about 10kWh each night on cheap electricity.

In my mind I accept that heat pumps have to work harder when it’s colder and if it’s only this expensive to run for a few weeks of the year I reluctantly accept that.

I know you had problems leading up to the cold snap but hopefully you have found some settings you find acceptable now.

I stopped using the heat pump for hot water, it seems better to use the immersion heater on cheap electricity overnight.

29

Hi Christian & William ,

Many thanks for the information about your Heat Pump energy consumption during winter.

Your actual Maximum consumption during Dec/ember figures of between £25 and £30 per day are very

useful.

I certainly did not appreciate the quantifiable reduction in Heat Pump efficiency below -2 C.

This efficiency reduction occurs when the outside temperature is very low, with the energy demand high.

I also, did not appreciate the 2 Kwh of energy required to de-ice the Heat Pump.

This de-icing is accompanied by numerous warnings about excessive energy consumption , and,
large volumes of white Vapour / Steam.

Measurement:

As lord Kelvin said “if you cannot measure it , you don’t understand It”.

My “installer” still has not, after seven months, installed the two Electricity consumption meters supplied by Samsung/Telford.

My Energy supplier, Shell, has still not supplied , after 11 months of complaints, a working Smart meter Display.

I have built a Consumption meter from an Arduino which seems to provide accurate and high resolution
measurements of energy consumption. Lord Kelvin would, doubtless, be turning in his grave, but it seems to work!

Energy consumption reduction:

With a 500 Kwh demand for electricity during December I was forced to choose between "Hypothermia and a huge electricity bill.

I chose Hypothermia , reducing my electricity consumption by:

1: Reducing the Room Thermostat setting to 12 C at night.
2: Reducing the Weather compensation to 40 C Flow water Temperature at -8C outside temperature.
3: Switching the Heat pump OFF when the Water Temperature is above the room Thermostat Temperature using the Field values 2091 option 4.

Water Flow Temperature :
With Field option 2091 set to option 4 the water flow Temperature logic appears to be :

IF ( Room Temperature > Room Thermostat Set Temperature )
THEN
do nothing, Heat Pump becomes dormant.

  **ELSE**
             **WHILE** ( Water Flow Temperature  <  Water Law Thermostat setting )
                           Increase the Water  Flow Temperature 
             **ELSE**
                            do nothing.

These settings work, reducing the Electricity consumption while allowing the Weather compensation Thermostat and the room Temperature Thermostat to work. I appreciate that switching the HP into a dormant condition may be questionable.

The heat pump was delivered with Field setting 2093 used and 2091 and 2092 not used. A condition resulting in large electricity consumption and Bills during the winter months…

Note that the 2091 Option 4 tries to limit the Water Law Thermostat from “cycling” about the set Water Law Operating Temperature. Selected by trial and error.

Please, gently, tell me your thoughts. I have probably got it all wrong …but it works!

My next move will be to stop the Hot Water !!!

ian

30

Hi Christian & William,

In writing my previous E-mail I clarified the operation of my Samsung in my Head:

Samsung Field Option 2091 Option 4:

Call the Heat Pump ONLY when:
The Room Temperature is Below the Room Thermostat Temperature **
** AND **
** The Water Flow Temperature is Below the Water Law Thermostat Temperature.

The Water Law Thermostat consumes more energy in switching from ON to OFF than OFF to ON.

This Switching energy asymmetry limits ON-OFF Cycling.

ian

31

I think 2091 is a key difference between your system and mine, which is set to “Use signal on/off WL interlink off water pump 3”. I think this is because I am using a Wi-Fi smart thermostat which just gives a run signal or not.

What sounds most wrong about your system to me (I’m no expert by the way) is that you say it was using 2kWh to defrost. My energy usage drops quite low while defrosting, I assume that’s because it is just pumping water from the system around the HP. I have a vague recollection from when we were choosing a heat pump that they may have a heating element in the outdoor unit to help out in extremes, maybe something is happening to cause this to kick in?

32

Hi Christian,

Again many thanks!

Samsung’s Manuals:
I am appalled by the Technical Authorship of Samsung!
The resulting manuals are plainly translated from the Korean by someone who does not have any experience with the Heat Pumps themselves!

Field Parameter 2091:
Given that weather compensation saves a modest 10% on energy costs I have used Weather Compensation.

Setting the 2091 Field parameter to Option 2,3 or 4 switches ON weather compensation.
The front screen shows the Heat Pump in Weather Compensation mode with a +/- 5 C control.

Selecting option 1 stops weather compensation.
The Front screen shows the flow water Temperature with a typically 37 C presentation.

With 2091 set to option 4 my Honeywell mains switching Thermostat controls my secondary , Radiator motor .

With 2091 set to option 4 the Water Law thermostat displayed on my front panel, controls the Heat Pump

So, with 2091 set to option 4 I can control both the Radiator loop pump AND the Run command for the Heat Pump.

The Two thermostats , Room and Water Law, control the Heat Pump water temperature and the Radiators.

As delivered , and later set by my “installer”, my Heat Pump had only 2093 option 2 used.
The Water Temperature was then only limited by the Water Law climbing ( trying to climb ) to a flow temperature of 50 C from an outdoor temperature of -6 C.
This consumed a large amount of energy …Kwh and £££.

Most of the 2kwh of energy consumed in trying to increase the water temperature to 50 C.
Energy_Kwh_15-19.pdf (25.5 KB)

However, also during the night a large burst of electrical energy was observed.
power_Dec_15-19.pdf (33.8 KB)

These violent pulses were accompanied by the emission of large clouds of white Vapour or Steam .

The power consumption for 3rd to 4th Jan is shown after the changes to the Field parameters.
power.pdf (10.0 KB)

for reference look at the Power consumed between 15th to 19th December before the 209* changes.
power_Dec_15-19.pdf (33.8 KB)

No Power or Energy Consumption at all during the night !
energy.pdf (20.3 KB)

The Temperature graphs show no energy transfer from the Tanks to the Heat pump.

abs_temp_HP.pdf (9.2 KB)

I am also very sceptical about my conclusions …I will await the return of very cold evenings!

ian

33

Some years ago, by a roundabout route, I got to help an Englishman living in Germany who’d taken on the task of translating German instruction manuals for electrical training rigs into English. Fortunately, I knew more about Electrical Engineering than the German technical author, so I was able to send back obvious (to me) errors for correction.

I commiserate with you, but I know nothing about heat pumps so I can’t really help. I appreciate you invoking William Thomson, but I think he might have frowned on you writing the unit for energy as Kwh, because K denotes the unit of absolute temperature named in his honour. (What you wanted is kWh, honouring James Watt with the capital letter.) :smile:

34

Hi Robert.

Yes I must apologise to William Thomson , Lord Kelvin. :joy:

I mistakenly quantified energy in Kwh instead of kWh…

Seriously, I have long campaigned for the abandonment of KWH ,kwh or KWh in favour of Joules !

Kwh of energy is often mistaken , specially by Heat Pump and Solar panel salesmen , for kW , kilo Watts of Power.

1 KWh = 60 X 60 = 3600 Joules = 3.6 kJ. No ambiguity !

The Samsung manuals exhibit another serious flaw in that the “Weather Controls” seem to have been shoe horned into an existing software control system.

Flow water Temperature control should be a separate selectable option.

Weather Compensation control another separate selectable option.

An aside :slight_smile: William Thomson ,Lord Kelvin, however, got one thing very wrong:

“that Electricity , Magnetism and light share a common kinship” , James Clark Maxwell 1862.

ian

35

Hi William,

Have I got short cycling?

Looking at the attached graph of power from 15th to the 19th December the violent short cycling is obvious during the nights.

power_Dec_15-19.pdf (33.8 KB)

Violent short cycling?

I have reduced my Energy consumption by reducing my night time room temperature.see attached graph for 3-4th Jan.
power.pdf (10.0 KB)

Have I covered a far more serious fault , massive short Cycling?,

I have , of course , no confidence in my “installer”.

ian

36

Hi Ian,

I know your last question was addressed to William but I have to query your charts, as the power scale shows really low numbers, less than 1kW - that doesn’t sound like what you are describing.

I also query whether you are showing kW or kWh, I know you know they are different.

I think you need to zoom in on a specific time period as 2-4 days does not let us see infer what may be going on.

Something like instantaneous power (kW) in 10-30s intervals over 5-6 hours or less might be more useful. It would be good to see flow (& room) temperature over the same time frame although the frequency may be less.

1 Like
37

Perhaps to James Clerk Maxwell too?
:wink: :grin:

38

HI Ian

Given you are in Scotland, you will be on a different section of the efficiency continuum to me, and will have many other differences, bearing that in mind …

In my first couple of days I came to the conclusion that cycling was impacting efficiency, not to mention potential additional wear and tear on the compressor … so

… despite the lack of data/evidence , I have changed my heat pump to be always on, shifted the flow temperature (WL) curve down a bit, set the delta T to 3 degrees. The only thing I am adjusting at the moment is the flow rate. Lower at night and higher in the day.

Having said that and in line with what Christian just mentioned, I don’t really have enough data to be sure about the optimum configuration for maximum efficiency and reasonable comfort is.

Right now, I am making sure that the bathroom and living area (which both have UFH) are comfortable, and the rest of the house will be as warm as the radiators (at the same flow temperature) can get to. That way I can have maximum efficiency and the two important rooms warm enough, but not waste money heating rooms that we don’t spend a lot of time in or need the warmth for various reasons.

As Christian said, and inline with what I am going to do as soon as possible, is to monitor the following

outside air temperature
wind speed
flow rate
flow temperature
delta T
room temperature
HP electric consumption

Only then will I start to be able to understand what to tweak.

One final important point, radiant heat has a different effect on perceived comfort, something I am conscious of, that may somewhat undermine my plan. [lower room temperature with UFH will have same comfort level as a room with radiators heating the air to a higher room temperature.

William

39

Hi Christian,

I have measured the power by calculating the RMS of the voltage output from a Current Transformer, CT, connected across the mains input to the Heat Pump and Tank controller.

I have used a 10 second RMS sample period to provide a high resolution measurement of power.

The Energy measurement is calculated by summing the power measurements over time .

The energy measurement has been calibrated with a commercial energy meter. Not ideal but accurate enough.

I calculated the energy used from 1400 on the 4th Jan to 1000 on the 5th Jan as 8.9 kWh.
The Heat pump showing 10.6 Kwh from 1200 on 4th to 1200 on 5th…
energy.pdf (14.7 KB)

So, I am 80% confident my readings.

I am now interpreting the violent cycling during the night as the Heat Pump being unable to supply enough power during the very cold nights.

Simply put , the Heat pump is not powerful enough !

ian

40

Mine used 17kWh for the same period, with outside temperatures starting at 13c, down to 8.2c overnight then back to 13c.
At 40.75p/kWh this will have cost me just under £7 which I am okay with.

Have you looked at the control unit’s own energy consumption vs energy generation figures?