@technogeek 

Again ,many thanks for your advice , and your examples.

Samsung Answer please!

Could Samsung please  explain the purpose of the Water Pump Options 1, 2 or 3 of the Samsung 2091/2092 and 2093 controls!

Could Samsung please  explain the Pulse Width Modulation Motor Control compared to the AC Motor control option?

Thermostat Cycling?:

Like yourself I have been in some difficulty in measuring the effect of the Change of Cycle Period during this warm weather.

However, The COP has  , so far, seems considerably improved.

My Cycle Period has  doubled  to circa 20 minutes with a Run Time of circa 6 minutes!

The Losses , and the COP as measured at the start of my Radiator circuit have however  remained poor.

Measurements in Hot Weather?

My Sharky, in water,  Power Meter, with a round off to 1 ( one) kWh is a pain when my Samsung has a round OFF of 0.1 kWh and my Arduino CT Transformer 0.01 kWh !

In Hot weather, therefore,  All measurements become very Noisy in hot weather.

Samsung 2091/2092 Water Pump options 1, 2 or 3?

I have been aware of the effects of the Water Pump options on cycling for some 18 months.

A visiting French Samsung Engineer when asked what was the purpose of the Water Pump options replied , with disarming honesty " that he did no Know the purpose of the Water Pump options 1 to 4 ..........................................but that he thought Not Much!".

Could Samsung please  explain the purpose of the Water Pump Options 1, 2 or 3 or 4 of the Samsung 2091/2092 and 2093 controls!

Samsung Pulse Width Modulation Option ,Case 1 or the AC motor , Case 2 Option :

The visiting French Samsung Engineer spent a considerable time explaining the older case 2 , AC Pump motor control.

When asked to explain the case 1, Inverter Pump motor control he again, with disarming honesty declared that "He did not understand the INV Pump option !

He declared that "Only the Germans truly understand how the Pulse Width Modulation Motor Control really works!".

My Samsung has BOTH options installed, but the INV pulse width is corrupted !!

Samsung Plumbing:

I agree with you I would need to open another topic about the plumbing of my Samsung Heat Pump.

However, I have lost all confidence in my "installer," the MCS and the NIC , not forgetting the politicians and the  experts .

NIC / MCS Wash their hands

The NIC have said that , for me , my installer having been "STUCK OFF for the third Time , Nothing can now be done!"

@mike-h sadly due to installation and system design (bivalent system) constraints I have had to use an external thermostat which has the (#2091/#2092) options 1 to 4 to choose from.

One day when leccy is permanently cheaper and oil has got too expensive I will be going heat pump only. For the moment I run (automatically) the oil boiler at times when the heat pump becomes uneconomical, usely at an outside temp of below 5C at the moment.

Regards

@mike-h 

Water motor controls:

For clarity, are you using the internal Samsung Thermistor at the rear of the LCD panel, i.e. 2093 ?

What Pump motor options are you using under 2093?

Are you using the Pulse Width Modulation Motor control , case 1

OR

AC motor Relay control,  case 2?

@technogeek

Could I ask a , for me , some potentially embarrassing questions about Water Motor speed control on Samsung Heat Pumps?

Q1: Should I use the continuous Pulse Width Modulation Control, case 1 in the installation manual ?

Q2: Should I use the Binary Switching , and therefore noisy , AC motor control, case 2 in the installation manual?

Q3: Given that my Heat Pump uses Field bit 2091 ON  with Water Law 1 , should I use the resulting Weather compensation screen & Control?

Q4: Should I use Field bit 2093 ON with 2091/2092 OFF with the resulting control and display of Water Temperature.?

Which do you use?

I am confused , does the 2093 ON , 2091/2092  OFF stop  Weather compensation Control?

My visiting French Samsung engineer was unable to answer,  these , and numerous other questions!

C'est la vie.................

Perhaps he is correct in saying that "only the Germans Really understand Samsung Heat Pumps!"

@iantelescope there is no embarrassing questions!

Posted by: @iantelescope

↑

Q1: Should I use the continuous Pulse Width Modulation Control, case 1 in the installation manual ?

Pulse Width Modulation (PWM) pumps are a special kind of water pump that has a control signal that enables the Samsung controller to vary the pump speed to maintain a specified delta T across your emitter circuit. By changing the pump speed, you change the flow rate and hence the heat power being delivered to the emitters. This is used in conjunction with the weather compensation if I am correct.

Posted by: @iantelescope

↑

Q2: Should I use the Binary Switching , and therefore noisy , AC motor control, case 2 in the installation manual?

This is for the use of a fixed speed pump which is NOT interchangeable with a PWM pump. Secondly the terminal this pump is connected to can only supply 500mA max therefore the Samsung controller MUST control the pump through a relay.

I am not sure what you hope to achieve but unless you have deep knowledge of the required flow rates, pump head pressures etc for your system I would strongly recommend you leave it alone as you may even make the situation 10x worse for yourself.

Posted by: @iantelescope

↑

Q3: Given that my Heat Pump uses Field bit 2091 ON  with Water Law 1 , should I use the resulting Weather compensation screen & Control?

If you are referring to the screen in your photograph, then that is not the weather compensation screen. What I am seeing there is you have added 1.2C offset to whatever the water law target temperature has been calculated to be. This offset value should be zero (0.0C). Your water law parameters are configured using field options #201* and #202*. The offset is for temporarily increasing your flow temp hence heat input to the building if you feel cold but return to 0.0C afterwards.

Posted by: @iantelescope

↑

Q4: Should I use Field bit 2093 ON with 2091/2092 OFF with the resulting control and display of Water Temperature.?

The internal thermostat for the Samsung is located within the control panel in your picture. If you use #2093 and disable #2091/#2092 you will need to have that control panel rewired to the same location as your Honeywell thermostat otherwise it is not going to monitor the correct temperature e.g your lounge.

Posted by: @iantelescope

↑

Which do you use?

I am confused , does the 2093 ON , 2091/2092  OFF stop  Weather compensation Control?

As far as I know no, as long as either option 2, 3 or 4 are selected for #2093. As I have not got this arrangement I could be incorrect in my information about how it works.

I have attached a bunch of pictures with my various settings in the hope this will help.

@technogeek 

Hi , again, many many thanks for your patience and practical input.

Like yourself, My background is also in electronics/Electrical.

I am far happier with Electronics than plumbing............

Pulse Width Modulation, PWM and Delta_T across the Radiator circuit:

I agree with you that the PWM motor  system is designed to set and control the Delta_T across the Radiator circuit.

Heat Exchanger:

My System has a heat Exchanger fitted to isolate the Heat Pump from the Radiator Circuit.

Any changes in pressure and flow rate in the Radiator circuit do not affect the Primary water circuit pressure or flow rate.

Only changes in Temperature are transmitted between the Primary Heat Pump and the secondary Radiator circuit.

TWO PWM Controlled motors:

With two water circuits separated by a Heat Exchanger my system has TWO PWM Motors fitted.

As supplied , neither PWM cable input to these PWM motors was initially supplied.

On connection the Primary PWM Motor signal , supplied by the control board was :

Notice that the PWM Signal, although present, was offset by some 6 volts , and  incapable of driving the GRundfoss PWM Motor  on the primary water circuit.

To test both PWM Motors I generated a PWM signal from a  Arduino :

Both PWM Motors performed flawlessly . The PWM Motors have no faults.

The Pulse Width Signal was generated by measuring the Delta_T , the Temperature Difference between the primary Heat Exchanger ports .

The Primary Delta_T was measured , and controlled , using a pair of DS 18B20 Temperature Sensors connected, as inputs,  to the Arduino.

The Secondary Delta_T was, initially,  fixed at a Pulse Width of 100 us.

I am trying to  optimise  the Delta_T on the secondary circuit by varying the PWM Motor signal to both motors.

Hope you have followed my , probably incoherent , Technical authorship!

@technogeek 

Again, many thanks for your help and patience, I really do appreciate your experience .

Samsung Water Law:

I use the Thermostat Control Screen:

With this display  I can set the Temperature Offset of the Weather compensation Thermostat by +/-5 C:

 Increasing  the Thermostat Temperature when requiring more Power during Winter Cold.

Decreasing the Thermostat Temperature when limiting the Electricity bill!.

A delicate balance, speed of room temperature increase  against economy.

Winter Water Law Adjustments:

During cold Winter days , even setting the Thermostat Offset  to it's maximum , +5 C ,my house remains cold until late in the evening. 

With lower Scottish Temperatures I have permanently decreased the 201*  Weather compensation, High , Ordinate to -5 C. ( Samsung's recommendation).

With lower Scottish Temperatures,  during Dec and Jan , I  increase the 202*  Weather compensation Low Co-ordinate  to +35. C.

With lower Scottish Temperatures,  during Dec and Jan , I  increase the 202*  Weather compensation High  Co-ordinate to +50. C.

Even with these Winter settings the Heat Pump is often unable to supply enough Power to heat my house in a reasonable time, and I must use a 1.5 Kw backup Room heater.

Please accept my apologies , in advance, for my "Technical authorship".

@iantelescope I follow what you are saying however the issue is the Samsung controller is only capable of controlling one PWM pump not two. That means your second pump will in effect be controlled open loop from the Samsung controller.

I thought the main reason for this discussion was to reduce or eliminate the cycling of your system in the hope it will improve your overall performance?
Trying to adjust the flow rates of the system to me seems a lot of work for what could be very little return.

I assume the reason you have a heat exchanger in your system is to have complete fluid isolation between your primary and secondary circuit because you have glycol or some kind of antifreeze in the primary circuit water?

If you simply have a set of balanced radiators on the secondary emitter circuit then providing these are all open, ie there are no TRV's closing the radiators off during operation and the TRV is set to 2 or 3 degrees above the desired room temperature, then you should have a fairly constant flow rate.

The reason why thermostats cycle is primarily to match the heat source output to the heat load. For example, if the heat pump is producing 4Kw/h and your buildings heat loss is only 2Kw/h then the thermostat duty cycle is going to be roughly 50% which would then produce the amount of heat into the building of 2Kw/h to maintain the internal temperature. In your case, 10mins on and 10mins off which would run your heat pump for a total of 30mins (3 x 10mins) in an hour. 

Based on that theory, to better match the power output of the heat pump to the heat load at any given outside temperature you would be better adjusting the flow water temperature (LWT) for a fairly constant flow rate in your radiators as the heat load increased or decreased. This means the thermostat duty cycle will always be near 100% calling for heat and your heat pump gets more efficient because it is not having to produce such hot flow water and will run for longer periods per hour if your heat pump output is better matched to the heat loss curve of your house.

When setting my system up over the winter I used the following method because I do not have heat monitoring and meter equipment installed on my system:
(NB I was not sure if to publish this or not as it opens the topic up to disagreements but it worked for me)

My Heat Pump Configuration Strategy

As my system does not include monitoring equipment (other than Samsung in built monitoring) such as heat meters and electrical meters to detail the system performance and indicate where improvements can be made, I had to resort to some mathematics and measuring with logging thermometers. This was my process:

Heating System Configuration

One Samsung Gen6 12Kw High Temperature Quiet monobloc heatpump suppling, via a PWM pump, low loss header and fixed speed secondary pump, 11 radiators and 2 bathroom towel rails.
This system is conrolled by a Honeywell Home smart thermostat which has the capability of changing its duty cycle to best match the heat demands of the building by changing the amount of time it demands heat ("on" time) within a cycle. Cycles can be configured to be 3, 6, 9, 12 times an hour. My system is configured to 3 cycles per hour for both the heat pump and backup oil boiler when switched in.
The heating profile of the thermostat is set to heat the house to 21C from 5am to 10pm and 19C from 10pm to 5am 24/7. As the house takes most of the night to cool to 19C the pump does not operate during the cold inefficient night time.

Heat Loss

After a heat loss survey of my property, it was calculated that for an external temperature of -2 Celsius the heat demand of the property was 10.285Kw/h.
As I have an oil boiler with a metering grade flow meter attached, this figure was verified as reasonably accurate because in similar environmental conditions the oil boiler consumes approximately 1 litre keroscene per hour. Calorific value of keroscene is 1 litre = 10.1Kw.

Now that I had this information I could calculate the heat loss coefficient for my building using the following formula:

Total Heat loss per hour in watts / (Indoor Temp - Outdoor Temp) = Heat loss coefficient w / K E-1.

So for my property this would be: 10,286w / ( 21 C - -2C) = 447.2 w / K E-1.

Now that I had the heat loss coefficient I could calculate the heat loss of my building for every external temperature degree while maintaining a constant internal temperature of 21 C using the formula:

Heat Loss per hour (watts) = Heat Loss Coefficient (w/K E-1) x (Internal Temp - External Temp)

This resulted in the following:

OAT (Celsius)   Heat Loss Kw/h
-2                      10.2856
-1                      9.8384
0                       9.3912
1                       8.944
2                       8.4968
3                       8.0496
4                       7.6024
5                       7.1552
6                       6.708
7                       6.2608
8                       5.8136
9                       5.3664
10                     4.9192
11                     4.472
12                     4.0248
13                     3.5776
14                     3.1304
15                     2.6832
16                     2.236

Radiator Balancing

It is recommended (Heat Geeks et al.) that TRV's on radiators should only be used as temperature limiters and should be set 2 or 3 degrees above the desired room temperature to keep interference with the flow rate of the circulating water to a minimum.
Based on this advice, I opened up all the TRV's fully and spent 2 weeks using some logging thermometers in various rooms, tweaking the lockshield valves on each radiator until I had a fairly even temperature throughout the house, in my case 21 Celsius.
Once I was happy with the radiator balance and was confident that my flow rate in the system would be fairly constant, the temperature of the house would then be solely controlled by the leaving water temperature of the heat pump and thermostat operation.

Weather Compensation (Samsung Water Law)

At this stage I decided that the Honeywell thermostat was now going to be my best friend in finding the optimum heat curve for my building.
The thermostat duty cycle is determined by the imbalance between the heat source and the heat load.
So roughly speaking if a heat load (house) requires 2Kw/h and the heat source produces 4Kw/h then the duty cycle of the thermostat is going to be approximately 50% to only run the heat source a total of 30 minutes to achieve the required 2Kw/h for the heat load.

Based on this theory I decided if the heat source is matched to the heat load then the thermostat would have an approximate 100% duty cycle for any given outside temperature, ie calling for heat all the time and the heat load temperature would be stable at the desired set temperature.
If the thermostat duty cycle was less than 100%, then the heat source was producing too much heat for the heat load and so the flow water temperature needed to be reduced. If the thermostat duty cycle was 100% but the temperature of the heat load was less than the set temperature or was falling in value, then the heat source was not producing enough and needed to be increased.

With a fairly constant flow rate from the heat pump, the only option open to me was to vary the flow water temperature via the weather compensation. Over the Winter months I then proceeded to monitor the thermostat duty cycle keeping the duty cycle as close to 100% as possible but maintaining the house at 21 Celsius by adjusting the weather curve settings to increase or lower the flow temperature for a variety of known outdoor temperatures.
After creating a number of points on the weather curve, the remaining points on the curve could then be interpolated by adjusting values SminFT, SmaxFT, SminAT and SmaxAT of the following formula to best fit the measured flow temperature points:

[(OAT - SminAT) x ((SminFT - SmaxFT) / (SmaxAT - SminAT))] + SmaxFT

where:

OAT = OutsideAir Temperature
SminFT = Samsung water law minimum flow temperature
SmaxFT = Samsung water law maximum flow temperature
SminAT = Samsung water law minimum air temperature
SmaxAT = Samsung water law maximum air temperature

Setting the water law points SmaxAT = 10C : SminFT = 35C and SminAT = -2C : SmaxFT = 45C
gave the final set of figures:

OAT (Celsius)    Heat Loss       Flow Temperature Celsius
-2                         10.2856        45.00
-1                         9.8384          44.17
0                          9.3912          43.33
1                          8.944            42.50
2                          8.4968          41.67
3                          8.0496          40.83
4                          7.6024          40.00
5                          7.1552          39.17
6                          6.708            38.33
7                          6.2608          37.50
8                          5.8136          36.67
9                          5.3664          35.83
10                        4.9192          35.00
11                        4.472            35.00
12                        4.0248          35.00
13                        3.5776          35.00
14                        3.1304          35.00
15                        2.6832          35.00

The thermostat now has a duty cycle close to 100% throughout the OAT range 10C to -2C which produces a combined DHW / CH COP of 4.3 at OAT 7C whilst maintaining the internal temperature of the house to 21C (Rural Cambridgeshire)

Due to the heat pump becoming a little unstable for flow temperatures less than 33 Celsius, the minimum flow temperature is kept at 35C from OAT 10C up to 15C. To achieve the very small quantities of heat needed above OAT 10C, the thermostat does start to reduce its duty cycle. By then I am switching the heating off as it becomes uneconomical and pointless to run when the solar gain during the day heats your house for free!

Regards

@technogeek 

Wow , a superb , and detailed description of the design , and build , of your system. Many thanks again.

My Installer:

My Heat Pump was "installed" by a supposedly "professional" Heat Pump installer who has been STUCK OFF by the NIC, on , at least three occasions during the last Two years.

My Heat Pump design:

My House Heating requirements were "Calculated" for a 6.5 kW Heat Pump.

My Installer fitted a 5kW Samsung , subsequently "Altering the Heat requirement Calculations " to justify the installation of the 5kW Samsung". The NIC STRUCK OFF my installer for this , their first "indiscretion".

5 kW Samsung installation:

On arrival the Samsung was "installed" without:

1) A Water Flow sensor subsequently found and wrongly fitted into four different positions on the pipe network. The Water Flow Sensor was replaced some four weeks after "installation" when found to be "faulty"..

2) A Primary Water Expansion vessel with two missing PRV's.

3) A Thermostat , subsequently "installed " with my "installer" "not realising that a Thermostat was required"!

On arrival my Heat Pump, came , without explanation , fitted with a Heat Exchanger separating two Grundfoss PWM Motors.

The Primary Grundfoss motor was controlled by the On-Board Relay.  

The Secondary Radiator Pump  was , eventually ,  connected to  the Honeywell Thermostat.

My Own Heat Requirement Calculations:

With absolutely no confidence in my "installer's " Calculations I used my own Calculations based on ACTUAL Measurements .....

very like yourself!

I fitted an electrical Power/Energy meter to a 1.5 kW Oil filled Room Heater.

I then monitored the Indoor Room Temperature and the outdoor air Temperature recording the Power/Energy over a 6 hour period for each room in my house.

For my Living Room , for example, the Actual , measured Thermal Conductivity was 78 Watts per Delta_T degree C.

For an internal , room Temperature of 21 C , and a minimum outside Temperature of -5, Delta_T = 26 C .

Giving the total Power Requirements for my Living Room as 26 X 78 = 2 kW.

Glad to see that you adopted a similar approach to Room Temperature Measurement.

Multiple Heat Pump Faults....

With My Heat Pump "Short Cycling " Samsung -Dallium , Samsung's Consumer  installation arm in Wigan intervened asking that they would fit a Buffer Tank  to reduce the Short Cycling.

My "installer " then blocked Samsung-Dallium saying that "their boys could easily fit the Buffer tank".

After Two months the Buffer tank was "discovered" underneath the desk of the, by  now,  fired Installation Engineer!

Buffer Installation:

The Buffer tank, discovered under the desk of the, now former Chief engineer,  was "fitted" by "the Boys"  in Nov 2022 .

My installer was STRUCK OFF by the NIC , again, for "Altering" the Design to "justify the installation of the wrong Heat Pump." 

Investigations:

Samsung visited on Feb 2023, producing a "Report", subsequently delivered to, and hidden by , my "installer".

I have never seen ,the now, "Confidential" report................

@iantelescope I am trying to put a picture together of how your heat pump, 2x PWM water pumps, heat exchange, buffer tank and radiators are connected together.

Would it be possible to supply a diagram?

So far I have tried different combinations and basically even with my pigeon knowledge of hydraulics I cannot see how any of the combinations I have tried with the above components would work. Either the heat exchange is starved of heat and the heat pump overheats or the heat exchange and consequently the heat pump overheats but all combinations would, in my humble opinion, potentially starve the radiators of heat.

A diagram from your good self would confirm which configuration of mine is correct

Regards

Posted by: @technogeek

↑

@iantelescope I am trying to put a picture together of how your heat pump, 2x PWM water pumps, heat exchange, buffer tank and radiators are connected together.

Would it be possible to supply a diagram?

So far I have tried different combinations and basically even with my pigeon knowledge of hydraulics I cannot see how any of the combinations I have tried with the above components would work. Either the heat exchange is starved of heat and the heat pump overheats or the heat exchange and consequently the heat pump overheats but all combinations would, in my humble opinion, potentially starve the radiators of heat.

A diagram from your good self would confirm which configuration of mine is correct

Regards

If you search back through this thread (or possibly a different thread) you will find a schematic diagram for the system.

Advice was provided possibly over 1 year ago of ways in which it could be possible to improve the system. As far as I am aware none of the advice given was implemented.

@technogeek 

Many thanks for your friendly input. I appreciate your help and advice.

I , personally, did not design or install my Heat Pump.

The Heat Pump that arrived on 1st July 2022 was markedly  different from the original  Heat Pump selected on the basis of the original Heat Survey .

My Heat Pump Installation on 1st July 2022 -1st Aug 2022.

The Heat Pump that arrived on 1st July 2022 was fitted with a Heat Exchanger and two PWM Motors , one motor on each side of the Heat Exchanger.

My "installer" initially attempted to start the heat Pump without a Water flow sensor, the missing Water Flow sensor being later discovered in an unopened box arriving  with the Heat Pump.

The Water flow sensor was twice wrongly fitted into the Radiator water circuit resulting in numerous E911 , Low Water Flow errors.

The Water flow sensor was then wrongly positioned on  the Heat Pump Water circuit producing numerous E912 Errors.

The Water Flow Sensor was finally declared "wrongly manufactured" by my "installer".

A grand total of Six major missing , or damaged, components were  eventually fitted , with the Heat Pump eventually  starting on 1st august 2022 , some 4 weeks after the initial "installation ".

Short Cycling from Sept 2022

With Autumn the Heat pump was continuously "Short Cycling" with a Run period of 3 minutes on a cycle period of 8 minutes.

After several failed attempts by my "installer" to fix the "Short Cycling " Samsung-Dallium was invited to examine and repair the Heat Pump.

Samsung-Dallium and the installation of a Buffer tank.

Samsung-Dallium, of Wigan England, advised that they would fit a buffer tank to the system to "help " reduce "Short Cycling".

Samsung-Dallium later saying that the Buffer Tank would  "also help with de-icing and the large cloud formation coming from the Heat Pump.

My Installer's Technical Manager  then intervened ,attacking Samsung-Dallium , saying that, they, my "installer" , were "perfectly capable of installing a Buffer tank.

Buffer tank discovered under a table and fitted on 26th Oct 2022.

My "installer " "discovered" the missing Buffer tank under the table of the, now fired, Technical manager.

Two Technicians arrived on 26th Oct 2022 to fit the Buffer tank but " did not know where to install the buffer tank".

The Buffer tank was installed across the Input Ports of the Heat Exchanger.

Heat Pump PWM Performance, Today 12 June 2024:

With the Honeywell Thermostat now removed as a source of "short Cycling" I have concentrated on the Heat Exchanger performance..

The Heat Exchanger Output Delta_T , has been increased to 4..5 C by setting the Primary PWM Pulse Width  to 64 ms and the Secondary , Radiator, PWM  Pulse width to 125 ms.

The Heat Exchanger Output Delta_T  has increased from, circa 1.5 C to 4.5 C a improvement with the output temperature greatly improved.

I will continue to increase the Radiator Pulse width but cannot further increase the Primary Pulse Width without producing unwanted E912 errors indicating Low water flow rate.

AS you can perhaps appreciate, I am confident when dealing with Electrical / Electronic / Field bit variation but not confident about the Plumbing or the heat equations.

As perhaps you can also appreciate , I have been attacked, several times , at considerable volume ,  by my , now former "installer" for altering  "their carefully considered  settings".

My Crime Lese-majeste ?

My "Installer " has now been STRUCK OFF by the NIC for the Fourth time.