so both feeds to the HP line pumps go to the Samsung controller and the Circulation goes to this box in pic attached All pumps are the same spec .

Yes James , that is correct. 

To answer some of the points made by the contributors about the wiring , it does seem quite a mess. 

About two years ago I tried my luck to get a local sparky working for an Ashp plumber , they spent all morning scratching their heads then came with an answer that the sensor for DHW tank was faulty. When I bought it , I measured the resistance on it and it was the same reading as the original/

I then found a young guy working from Inverness and he found all the wiring in the wrong terminals on the board. He mostly swapped the way it was wired on the inside of the lid to be fair using the originals and did label them for his own use,

If it helps , and perhaps not at this distance I can do further labelling. 

I really cant find anyone else that would confirm the present set up , unless Mars can find someone to recommend locally 

Posted by: @alfapat

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I really cant find anyone else that would confirm the present set up , unless Mars can find someone to recommend locally 

My strong gut feel is that, if you bypass the pump in the secondary, turn the thermostat up to full, bypass the buffer, it will work.  Basically the heat pump will then have a continual call for heat which it will supply according to its own algorithms and WC.  It wont really 'see' much difference.  Since we know that one pump is sufficient for your secondary, its aapretty sure bet that the remaining two pumps will be sufficient.  Very likely you could delete one leaving only one pump.  It would however be best first to check the 2xxx FSVs.

If you go down this route you could try it, then tidy up the cabling (or not) depending on how it works (or not).

If it were my system I would do this, but not in the depths of winter.

 

I might do a bit of labelling, but found these diagrams . The field settings shown are the only ones I can relate to and using .

Sorry think I have two the same , don’t seem to be able to edit! 

 

@alfapat 

OK, thats very helpfu. If you just record your values for the FSVs in the first picture that should be fine.  Most will probably be as per the picture.

Posted by: @jamespa

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Posted by: @alfapat

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I really cant find anyone else that would confirm the present set up , unless Mars can find someone to recommend locally 

My strong gut feel is that, if you bypass the pump in the secondary, turn the thermostat up to full, bypass the buffer, it will work.  Basically the heat pump will then have a continual call for heat which it will supply according to its own algorithms and WC.  It wont really 'see' much difference.  Since we know that one pump is sufficient for your secondary, its aapretty sure bet that the remaining two pumps will be sufficient.  Very likely you could delete one leaving only one pump.  It would however be best first to check the 2xxx FSVs.

If you go down this route you could try it, then tidy up the cabling (or not) depending on how it works (or not).

If it were my system I would do this, but not in the depths of winter.

 

When you say one pump is sufficient for my secondary , which pump do you mean to take out of the system, probably CH? 2021 ON FSV yesterday evening , was dropped to 42 instead of 44 , mainly to see if it changed any values.Just to be clear we are looking at the difference between HP output and CH OUTPUT OR RETURN? Sorry should know by now!

Done bit of labelling and those white wires are four core but not all used.

 

Posted by: @alfapat

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When you say one pump is sufficient for my secondary , which pump do you mean to take out of the system, probably CH?

That is the one to be bypassed in the first instance.  You may also be able to remove the pump on flow or return, but I strongly suggest to proceed one step at a time.

Posted by: @alfapat

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Just to be clear we are looking at the difference between HP output and CH OUTPUT OR RETURN? Sorry should know by no

Not sure what you are asking, in what context?

Posted by: @alfapat

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Done bit of labelling and those white wires are four core but not all used.

 

Good.

Posted by: @alfapat

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2021 ON FSV yesterday evening , was dropped to 42 instead of 44 ,

Noted,  please can you check the other 20xx FSVs and post them just in case there are any surprises!

@jamespa

Just to be clear we are looking at the difference between HP output and CH OUTPUT OR RETURN? Sorry should know by now. 

The flow temp. from the Hp compared to the flow feeding the CH. 

The min. Requirement being 1c-2c obviously by time it’s being round the rads it’s less . 
The other FsV’s have not been Changed , so 2011 is set for -5c 

2012 for High ambient Weather comp. +15c

2021 Rads flow temp. In cold weather 42c

2022 Flow in mild 37c

2091looks for run sinal on B22

@alfapat  

2021-2022 make no sense, the difference is so small that its barely bothering with weather compensation at all.

I would set 2022 to 30 or even 27C

The 2091 value confirms to set the external thermostat well above the desired temperature whilst you optimise the WC.

 

Posted by: @alfapat

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Just to be clear we are looking at the difference between HP output and CH OUTPUT OR RETURN? Sorry should know by now. 

The flow temp. from the Hp compared to the flow feeding the CH. 

The min. Requirement being 1c-2c obviously by time it’s being round the rads it’s less . 

Sorry I still dont know what you are asking here.  For now I would concentrate on getting WC right and planning, if you intend to, the bypass of the buffer tank and secondary pump.   You are getting there, these things take time because houses respond slowly.

 

 

Really! That much of a drop . Should I be trying out that WC anyway, I was just trying to see if there would be a difference between flow from HP and flow out of buffer to CH with the change in WC . Ultimately warm of the house. 
I do intend to make changes in the set up , but as an interim lower and monitor. 
I have talked about lowering in this thread before, but haven’t realised that my efforts in small changes were so fruitless. 
I am just conscious that the costs are so much more at the present setup, than before with my previous one , albeit still too much, patience I suppose? 
So should I be trying to lower WC at this stage, Oh I will try it ! 
What can I lose. 
Desperate times , I’m doing my head in at this thing , where’s my plumber, I’ve never had one , away to find! 

Posted by: @alfapat

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Really! That much of a drop

Absolutely.  37@15 makes no sense whatever.  The whole point of WC is to adjust the flow temperature so that the output of the radiators (which depends on the difference between flow temperature and house room temperature) just matches the demand (loss from the house).

At an OAT of 15 there is almost no demand (assuming you want your room temperature to be about 20).  Obviously the house does still lose heat at this temperature (because its warmer than the outside) but there is usually enough waste heat from electrical items and heat from the occupants to come close to balancing that loss.  So a very good starting point for the high end of WC (IAT=15) is only just to heat.  30 or even 27 does that.  More importantly, unless you get this right, the flow temp will also still be too high in the 7C-12C region, which is where the OAT is most of the time and where most of the money is spent.  Please change 2022 to 27 or 30 if it wont let you set it to 27.

(For what its worth the reason some people set a 'floor' of 37 is because its the lowest temperature at which radiators still feel warm and doing this avoids 'my radiators aren'

t warm' call outs.  This is silly and costly, the radiators emit heat even if they don't feel particularly warm and its the house that you are trying to heat not the radiators!).

Please change 2022 to 27 or 30 if it wont let you set it to 27.

 

Posted by: @alfapat

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Should I be trying out that WC anyway, I was just trying to see if there would be a difference between flow from HP and flow out of buffer to CH with the change in WC . Ultimately warm of the house. 

There wont be much of a change in the temperature difference across the buffer as a result of changing the WC parameters.  However its ALWAYS right to adjust the WC down to the minimum value consistent with heating the house.  You need to set 2022 to 27 or 30 then gradually reduce 2021 until the house is just at the right temperature, with all thermostats and TRVs set to max.  Better still reduce it until the house is just below the right temperature, then turn it up a degree.  Thats (more or less) the optimum for your current setup.  If, later, you remove the buffer, you will need to readjust.

Posted by: @alfapat

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I am just conscious that the costs are so much more at the present setup, than before with my previous one , albeit still too much, patience I suppose? 

For me to comment on this I would need to know the details of what you have changed, the OATs on the two days before and when you determined the costs, and the actual measurements of costs.  However I can say that the fact that FSV 2022 is so high (which has only just come to light) will tend to negate any savings due to WC when temperatures are in the 0-8 region, which they have been recently.  This could easily account for an increase because, effectively, you have opened up all the TRVs and thermostats without implementing WC.

 

The only way to do this is to see it through to the point where the WC is optimised, then test over several weeks.  And you have to be 'all in' or not in at all.  Piecemeal changes that don't complete the job are quite likely to make things worse.  In the end its your system so please feel free to go back to operating it as you had it previously.   

I'm quite happy to follow this through as it seems right to with all that is being advised, as its never been right since installation.

2022 is now at 27 and 2021 is 42\

Thank you for explaining that, I think I was getting mixed up with all the numbers.

Posted by: @alfapat

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I'm quite happy to follow this through as it seems right to with all that is being advised, as its never been right since installation.

2022 is now at 27 and 2021 is 42\

Thank you for explaining that, I think I was getting mixed up with all the numbers.

Its easy to get mixed up!

So now leave 2022 where it is and gradually adjust 2021 until the house is at the right temperature.  Allow a week, change once - max twice per day  The aim again is as low as possible while still heating the house.  Note that may mean you have to push it up a degree given the change you have made to 2022, but only time will tell!

BTW you are doing quite well to be able to run at 42 with radiators and a buffer tank, suggests that your radiators are plenty large enough!