Posted by: @iantelescope

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My Buffer tank was fitted, by my "installer"   across the Input ports of the Heat Exchanger.

My Buffer was originally "designed" by Samsung-Dalliam to be fitted on the HP  Water return to "protect the System against frost damage".

I seriously hope you don't mean what you say in the first sentence.  If you do, no wonder the system doesn't work.

Samsung is right, plumb it two pipe only, and in the return.  All it the does then is add to system volume which helps with the defrost cycle.  You need enough water in the system to survive a defrost (because thats where the heat comes from for the defrost) as well as to reduce cycling.

Posted by: @iantelescope

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 I would remove the Heat Exchanger myself ......were it not for the threats from my "installer".

 

At this stage do you care? He seems to be such a cowboy that you might be better off without him!

Seriously though, if the plumbing of the buffer tank and heat exchanger is as bad as you say (and judging by the temp drop across them it may well be), then IMHO you need to get this sorted, threats from installer or no!  Remember that each degree of temp drop between heat pump and emitters costs you about 2% in efficiency, or even more (3%+) if you are already running at a high flow temp.    This isn't heat 'lost', so it won't show up in another room, its the extra work the compressor has to do to generate the same amount of heat at the higher flow temperature.  It also reduces your system capacity which might account for it not being warm enough).

A diagram of the plumbing of heat exchanger, heat pump and buffer tank really would help.

@jamespa 

Hi james.

My "System"

Please find a drawing of my system.

The System was built  , piecemeal, from July 1st 2022 to Oct 30th 2022.

Sorry about the drawing but I cannot find a suitable drawing package for Plumbing for use on my "linux pc".

Does anyone know of such a package?

Notice that the Buffer is described as a "Volumiser " , this, a term used by Samsung themselves.

The Samsung specification calls for a HP pipe Volume of at least 20 litres.

A 50l "Volumiser " was recommended by Samsung, the pipe volume being only 6 litres.

I have received three different positions to install the Buffer.............................. to fix three different problems!

Piecemeal build.

My System was initially "built", and started, by my "installer" without, several components. 

Several components, including system metes , have still, some 15 months after starting , not been installed .

Loan dependent on System Quality

I applied for a loan and grant to cover the cost of the installation.

The Grant is dependent upon the "installer" issuing a certificate of quality assurance,

The "installer " has been struck OFF twice for incompetence and , initially , no quality assurance certificate was produced.

The HES and EST, in Scotland, eventually issued a partial payment, to me , covering my initial down payment.

The Remainder of the payment is dependent upon my "installer" producing a quality assurance certificate.

A rock and a heard place.

I would like to rebuild the system myself, removing the Heat exchanger and the Buffer..........but I may lose the Grant.

The NIC is restarting it's investigation..................

ian

• Posted by: @iantelescope

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@jamespa 

Hi james.

My "System"

Please find a drawing of my system.

-- Attachment is not available --

The System was built  , piecemeal, from July 1st 2022 to Oct 30th 2022.

Sorry about the drawing but I cannot find a suitable drawing package for Plumbing for use on my "linux pc".

Does anyone know of such a package?

Notice that the Buffer is described as a "Volumiser " , this, a term used by Samsung themselves.

The Samsung specification calls for a HP pipe Volume of at least 20 litres.

A 50l "Volumiser " was recommended by Samsung, the pipe volume being only 6 litres.

I have received three different positions to install the Buffer.............................. to fix three different problems!

Piecemeal build.

My System was initially "built", and started, by my "installer" without, several components. 

Several components, including system metes , have still, some 15 months after starting , not been installed .

Loan dependent on System Quality

I applied for a loan and grant to cover the cost of the installation.

The Grant is dependent upon the "installer" issuing a certificate of quality assurance,

The "installer " has been struck OFF twice for incompetence and , initially , no quality assurance certificate was produced.

The HES and EST, in Scotland, eventually issued a partial payment, to me , covering my initial down payment.

The Remainder of the payment is dependent upon my "installer" producing a quality assurance certificate.

A rock and a heard place.

I would like to rebuild the system myself, removing the Heat exchanger and the Buffer..........but I may lose the Grant.

The NIC is restarting it's investigation..................

ian

For what its worth I use libre office draw for almost everything.  Once you get used to it it cant do most things I need.  I use it on windows but of course its available for linux.

Why might you lose the grant if you change the system?

If I understand it correctly the volumiser bypasses the heat exchanger (which is, in fairness, what you said).  How that is supposed to work is anyone's guess (any offers?).  The HEX is likely to have a higher impedence than the volumiser (unless there some shut off valves) so Im pretty certain that it simply acts as a shunt for the heat from the HP, depriving the heat exchanger of the heat throughput it needs to be most effective.  Basically most of the heat from the heat pump is likely to circulate through the volumiser, which as the volumiser is not designed to emit heat (but of course will to some extent) is bound to cause short cycling whilst heating principally the room in which it is sited and depriving the rest of the property of heat.

From the diagram I cant tell whether the flows through the HEX are correctly plumbed or not (some of your arrows point both ways).  It is important (probably worth 10% in efficiency) that they go in opposing directions so the incoming water from the HP meets the outgoing water to the emitters.  Are you able to check this?

As Samsung have told you where the volumiser should go (and they are right) I would have thought you would have a very good argument for adding a piece of plumbing so that you effectively can have it in either location. 

Also Samsung mean engaged system volume not pipe volume.  Unless you have very few very low volume radiators or the system is configured so all the rads can be shut off at once (which it shouldn't be), there is no way that your engaged system volume is only 6 litres!

I would say that if the installer issues a certificate of quality, he is doing so fraudulently!  But perhaps you can find a way to encourage him to do so, collect the grant, then fix the system.  

Posted by: @iantelescope

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@jamespa 

Hi james.

 

My "System"

Please find a drawing of my system.

-- Attachment is not available --

The System was built  , piecemeal, from July 1st 2022 to Oct 30th 2022.

Sorry about the drawing but I cannot find a suitable drawing package for Plumbing for use on my "linux pc".

Does anyone know of such a package?

Notice that the Buffer is described as a "Volumiser " , this, a term used by Samsung themselves.

The Samsung specification calls for a HP pipe Volume of at least 20 litres.

A 50l "Volumiser " was recommended by Samsung, the pipe volume being only 6 litres.

I have received three different positions to install the Buffer.............................. to fix three different problems!

 

 

Are you saying that when heating is on, there's a parallel flow through the volumizer and the HEX rather than them being in series?

No wonder you cannot transfer the heat efficiently to the radiators, cuz only half gets the chance.

I  think you said you can switch the volumiser out.  So here, at helicopter level, is an outline suggestion.

Switch out the volumiser

Take off or turn to max at least half your trvs to guarantee system volume (the ones downstairs preferably or in the rooms you use most)

Check the hex is plumbed correctly.  If not fix it

If the Samsung isn't controlling it, adust the pump speed on the rad side of the hex to get about 5C delta t flow to return.

Run the system

If the rooms where the trvs are removed reach significantly different temps (don't worry if the them is right, only about the differences), try turning down the lockshields a bit on the hotter ones to get them closer.

If you can't get the rooms in balance with modest adjustments you may need a proper system balancing.

Now adjust the water law settings so that the rooms without the trvs are at the _right_ temperature.

Now you have a system which, with a bit of luck, is operating in the right ballpark and you haven't removed any components.

Posted by: @jamespa

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I  think you said you can switch the volumiser out.  So here, at helicopter level, is an outline suggestion.

 

Switch out the volumiser

Take off or turn to max at least half your trvs to guarantee system volume (the ones downstairs preferably or in the rooms you use most)

Check the hex is plumbed correctly.  If not fix it

If the Samsung isn't controlling it, adust the pump speed on the rad side of the hex to get about 5C delta t flow to return.

Run the system

If the rooms where the trvs are removed reach significantly different temps (don't worry if the the temp is right, only about the differences), try turning down the lockshields a bit on the hotter ones to get them closer.

If you can't get the rooms in balance with modest adjustments you may need a proper system balancing.

Now adjust the water law settings so that the rooms without the trvs are at the _right_ temperature.

Now you have a system which, with a bit of luck, is operating in the right ballpark and you haven't removed any components.

A couple more thoughts.

Instead of using the lockshields to balance the rads in the rooms where you have removed the TRVs, you could use the 'caps' that are provided with at least some TRVs to allow you to switch them off or manually adjust them.  Take off the heads, replace them with the caps, use these to get the rooms to the same temp (following the above).  This has two advantages - a) You have'nt disturbed any balancing that the installer has done so he cant complain and b) the TRV valves themselves have greater valve authority (effect on the water flow) than most lockshields so the adjustment will be easier.

Its just possible that taking the buffer out of the loop and removing TRVs wont work - if the CH side pump switches off when the system goes into defrost mode.  This is unlikely (as it doesn't seem, from what you say, to be controlled at all) but not impossible.  It wont cause a problem until the temp gets down to about 4C, but if this problem does occur then defrost probably wont work and the system will likely halt.  Notwithstanding this caution, that buffer has to change, the system simply cant heat your house properly with it set up as it is!

@jamespa 

Drawing package?

I am using Libre Office Draw. However, Libre Office Draw has no symbol library for pipe,Valves or Boilers.

Libre Office Draw is fine..............but has no plumbing symbol library.

Balancing the HEX?

The Heat pump was delivered with Two Grundfos UPM3 PWM Motors on either side of the HEX.

No PWM Cables were delivered with the system, PWM control being regarded as an "option".

I obtained Two Grundfos PWM Cables from Ebay.de , Ebay Germany.

Luckily, I discovered that the Arduino Mega can supply a compatible  PWM signal.

When driven from a Arduino Both motors perform flawlessly.

So, I have control of the flow rates on both sides of the HEX.

HEX flow control ?

Given that I have , uniquely, control of the Flow rates on both sides of  the HEX,

How should I control the flow rates ?

Official Samsung Flow control of Heat Pump flow rate ?

The only PWM output from the Samsung Control board does not work .

The PWM Signal dies when connected to the Grunfos HP Motor.

No control for the Radiator flow control!

The Radiator motor Grundfos PWM socket has no socket , or control, for the Radiator Grundfos motor.

A visiting French Samsung Engineer was unable to explain why the PWM control does not work.

He was also unable to explain where the Radiator PWM Signal should be connected.

Impedance?

I am well aware that the impedance of the HEX is larger than the independence of the Buffer.

Consequently, most of the water would "go the route of least resistance " and bypass the HEX.

What now?

I will try your excellent suggestion of trying to get a delta T of 5 C across the HEX output.

This was also the suggestion of the visiting French Samsung Engineer.

The French engineer did not , however, explain how the HEX balancing was ,physically, to be obtained.

Fear of plumbing.....and of my "installer"!

I have a fear of plumbing....especially when confronted by my incompetent "installer".

My "installer" is looking for any excuse to blame me , the customer, for the mess !

Missing French Samsung Report

My "installer" has never produced the French Samsung's Engineering report..................

Cynicism, incompetence ............................................cover-up

@fazel 

Many thanks Fazel.

Impedance?

I am well aware that the impedance of the HEX is larger than the independence of the Buffer.

Consequently, most of the water would "go the route of least resistance " and bypass the HEX.

The Buffer tank was, originally, sized , and positioned by Samsung-Dallium , Samsung's own maintenance arm.

Samsung-Dallium later changed the position of the buffer into the HP Return "to stop the problem of Winter freezing."

My "installer" in describing Samsung's intervention as "ludicrous" had "his own boys, install and fit the buffer tank".

On arrival , some two months later, my "installer's Engineers" "did not know why the buffer tank was required , nor, where it was to be positioned".

Unwanted, unneeded  HEX and Buffer

I have a system that has an unwanted , and unneeded HEX and Buffer.

Cheaper, and quicker  to Replace the entire system than to continuously repair my current system?

Each month , new evidence appears about the poor performance of this heat pump.

Maintenance for a Heat Pump "that does not exist"?

On 1st Aug 2023 the Tank manufacturer's Computer announced that " my Heat Pump requires it's annual service to maintain the guarantee".

On Contacting Telford , my Tank Manufacturer , I was told that "my Heat Pump did not exist , being currently unregistered."

Telford would NOT , themselves, perform any service in Scotland, recommending several companies who would.

No company would perform the service...................saying that "authorisation" would be required, and , anyway,  nobody knows what service is required!

BS 7593:2019

I was told that my non-existent Heat pump would have to be checked for pipe water quality.

On inspection , the water quality was poor, and, I called on the services of a local pipe Flushing company.

The Cost ......£600 .

ian

@jamespa 

Room Balancing??

My "installer" never balanced the TRV's in any of my rooms!!

System Bled?

My "installer" never bled the radiator circuit .................................

Radiators

I have now only Two working Radiators connected to the Heat Pump.

Only my living room is "heated" , and that poorly!

During last winter I relied on a 900 Watt Electric heater in my Living room .

Overconsumption Errors

The Heat Pump showed several "over consumption Warnings prompting  advice to move the goal post and "increase the Overconsumption level setting" !

My Energy costs , excluding the recent price increases was circa 60% greater than the comparable Gas heating consumption in the previous year.

This increase was attributed to the colder weather!!

ian

@iantelescope

Hi Ian,

I have been away for the weekend, so I'm just catching up with the saga.

Rather than jump about trying this and that, I would suggest adopting a systematic, logical approach, to assess how your system should be piped up for correct operation, and then how it may be optimised for best performance.

Looking at your schematic diagram, the 50L vessel would appear to be being used as a Volumiser rather than a buffer tank, though it is installed in the wrong location. From what I can see, your system should be piped up as follows-

The warmed water coming from the heat pump should go to the inlet of the primary water pump (Motor 1 in the schematic). The outlet from the primary water pump goes to the inlet of Valve 1 and Valve 2. I do believe that most systems have the primary pump located in the return pipework, so it may be prudent to check which is the flow and return connection on your heat pump, and that the water flow through the heat pump is in the correct direction.

When in Central Heating (CH) mode Valve 2 should be open, thereby directing the water flow to the primary inlet of the HEX. The primary outlet of the HEX should be connected to the inlet of the Volumiser, with the outlet of the Volumiser being connected to the return pipe to the heat pump via Filter 1.

When the system is operating in DHW heating mode, Valve 2 should be closed with Valve 1 now open. The primary water therefore flows through Valve 1 to the inlet connection of the heating coil within the hot water cylinder. The outlet from the heating coil should be connected to the inlet of the Volumiser, and therefore the water flows through the Volumiser on its way back to the heat pump.

I think that you stated that this is how Samsung had indicated that the system should be piped.

As far as the HEX is concerned, ensure that the primary water flows into the primary inlet which would normally be located towards the top, with the primary outlet being near the bottom. The secondary water inlet should be near the bottom, with the secondary outlet near the top. The primary and secondary flow should therefore be in opposite directions.

I would suggest that you ensure, or get, your system piped as I have suggested and then it should be possible to start adjusting your system for optimum operation.

Posted by: @derek-m

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@iantelescope

Hi Ian,

I have been away for the weekend, so I'm just catching up with the saga.

Rather than jump about trying this and that, I would suggest adopting a systematic, logical approach, to assess how your system should be piped up for correct operation, and then how it may be optimised for best performance.

Looking at your schematic diagram, the 50L vessel would appear to be being used as a Volumiser rather than a buffer tank, though it is installed in the wrong location. From what I can see, your system should be piped up as follows-

The warmed water coming from the heat pump should go to the inlet of the primary water pump (Motor 1 in the schematic). The outlet from the primary water pump goes to the inlet of Valve 1 and Valve 2. I do believe that most systems have the primary pump located in the return pipework, so it may be prudent to check which is the flow and return connection on your heat pump, and that the water flow through the heat pump is in the correct direction.

When in Central Heating (CH) mode Valve 2 should be open, thereby directing the water flow to the primary inlet of the HEX. The primary outlet of the HEX should be connected to the inlet of the Volumiser, with the outlet of the Volumiser being connected to the return pipe to the heat pump via Filter 1.

When the system is operating in DHW heating mode, Valve 2 should be closed with Valve 1 now open. The primary water therefore flows through Valve 1 to the inlet connection of the heating coil within the hot water cylinder. The outlet from the heating coil should be connected to the inlet of the Volumiser, and therefore the water flows through the Volumiser on its way back to the heat pump.

I think that you stated that this is how Samsung had indicated that the system should be piped.

As far as the HEX is concerned, ensure that the primary water flows into the primary inlet which would normally be located towards the top, with the primary outlet being near the bottom. The secondary water inlet should be near the bottom, with the secondary outlet near the top. The primary and secondary flow should therefore be in opposite directions.

I would suggest that you ensure, or get, your system piped as I have suggested and then it should be possible to start adjusting your system for optimum operation.

I would agree that this is absolutely the best way, however OP seems to be reluctant to replumb anything, hence my suggested sequence above which comes as close to achieving the same with minimal or no replumbing, as a way to get a completely non functioning system at least heating the house with reasonable efficiency.

Ultimately OP has to decide how to proceed. His system plumbed as it currently is plumbed is incapable of heating the house because the emitter circuit is effectively bypassed by the buffer.  He tells us he can switch out the buffer without replumbing, so if the imperative is to avoid replumbing for now, an interim solution based on this is the way to go (always assuming that a heated house is also a priority)

Ultimately though a proper replumb as you suggest is what's needed.

@derek-m 

Hi Derek,

Again , many thanks for your insight..................and experience

Programming OR Plumbing OR Both?

With the system in it's current state I can either

1) Control the Flow rates on both water circuits using the PWM Grundfoss PWM motor inputs.

With Flow rate control I can set the  cycling time or, alternatively ,  set the output power/Energy fed to the Radiators.

OR

2) Re-build the Plumbing to re-position the buffer in the HP Return pipe.

Plumbing ?

I have checked the flow directions through the HEX and the Heat Pump itself. Nothing wrong.

The Heat Pump motor is , however, positioned on the outward high temperature feed from the Heat Pump itself.

This is the position shown on all my Samsung installation  Diagrams.

Courage?

I will work up the courage to re-plumb the system either removing , or repositioning the Buffer/Volumiser.

I will also, optionally,  re-plumb the system to remove the HEX.

Both my "installer" and the NIC would , however, strongly object to my re-plumbing.