Buffer Tank Hot when Heating Mode Turned Off

[Dave Jones]

the issue with plumbers is 99% of them have no clue how to system design a ASHPO for efficiency. Any of them can throw a kit together using same principles as a gas boiler. 

 

This is one of the reasons they have such a bad rep.

 

If you see a roomstat anywhere you know for sure its a shit install. 

[JamesPa]

3 hours ago, Dave Jones said:

the issue with plumbers is 99% of them have no clue how to system design a ASHPO for efficiency. Any of them can throw a kit together using same principles as a gas boiler. 

 

This is one of the reasons they have such a bad rep.

 

If you see a roomstat anywhere you know for sure its a shit install. 

True but inexcusable. 

 

In most professions, indeed most jobs, you need to keep up with developments through ongoing training and, if you can't, or can't be bothered, you risk a performance improvement plan followed, if you don't succeed, by the sack.  Why do plumbers think they are different? 

 

Presumably because, for 20 years, they got away (and are still getting away) with setting up condensing boilers in a way that they don't condense, thus adding 10% to our heating bills.

Edited Sunday at 14:22 by JamesPa

[sharpener]

6 hours ago, JamesPa said:

I found this

 

 

The use of the word "ideally" rather gives the game away doesn't it? In contractual documents it recognises that the advice following it is not going to be observed by many/most recipients. You could anyway argue that the presence of lockshield valves is "some form of temperature control".

 

[JohnMo]

@sharpener a triple post! 

 

 

 

Thread now tidied, lol.

Edited Sunday at 18:06 by Nickfromwales
@sharpeners trigger finger

[SteamyTea]

4 hours ago, JamesPa said:

In most professions, indeed most jobs, you need to keep up with developments through ongoing training and, if you can't, or can't be bothered, you risk a performance improvement plan followed, if you don't succeed, by the sack.  Why do plumbers think they are different? 

And Vicars, not as if they can change horses mid stream.

[HughF]

22 hours ago, Dave Jones said:

the issue with plumbers is 99% of them have no clue how to system design a ASHPO for efficiency. Any of them can throw a kit together using same principles as a gas boiler. 

 

This is one of the reasons they have such a bad rep.

 

If you see a roomstat anywhere you know for sure its a shit install. 

 Nest + weather comp for us. Nest gives the wife an easy to use hi-limit (which is only rarely met in shoulder months).

 

I consider myself a good designer/installer.

 

heck, even the Samsung controller when used as a room stat is just that, an on/off stat. It doesn’t do load compensation, despite what people have been led to believe.

[James1234]

A fairly unsuccessful discussion with Daikin yesterday.. in summary they think the current install is very good and changing the ASHP to a smaller unit and removing the buffer tank would have a negligible impact on efficiency. 

 

Any recommendations for system designers that I could get contact to come out and review the system and give me some expert opinion to go back to the installer with? I am half an hour North of Bristol? Thanks in advance!

[Dave Jones]

1 hour ago, James1234 said:

A fairly unsuccessful discussion with Daikin yesterday.. in summary they think the current install is very good and changing the ASHP to a smaller unit and removing the buffer tank would have a negligible impact on efficiency. 

 

Any recommendations for system designers that I could get contact to come out and review the system and give me some expert opinion to go back to the installer with? I am half an hour North of Bristol? Thanks in advance!

 

look for a heat geek certified, they are the best about it seems.

 

https://www.heatgeek.com/heat-geek-elite/

 

[JamesPa]

7 hours ago, Dave Jones said:

A fairly unsuccessful discussion with Daikin yesterday.. in summary they think the current install is very good and changing the ASHP to a smaller unit and removing the buffer tank would have a negligible impact on efficiency. 

Curious given how different the design is to the one their guy originally specified!  Basically Daikin are therefore saying design doesn't matter much. 

 

All you are requesting, essentially, is for it to be installed in accordance with the original spec from which the plumber deviated only, so far as I can tell, because of parts availability.

Edited Thursday at 17:14 by JamesPa

[JohnMo]

9 hours ago, James1234 said:

Any recommendations for system designers that I could get contact to come out and review the system and give me some expert opinion to go back to the installer with?

First if Daikin hold the MCS licence the design has to be installed per your layout at the start of this thread. If the plumber was the MCS licence holder and issued the certificate, they are the designer, not Daikin, Daikin sketch is just that a sketch not a drawing. So you need to get your head around that side of things.

 

Running multiple circulation pumps kills CoP, often the second pump is driven from an unmetered (not metered by ASHP) supply. So secondary side circulation is missing from CoP. Example I just changed my pump in the ASHP from running all the time (manufacturer default) to intermittent as demanded from temp controller and cop increased by 1 to nearly 5 for the last week. I only have a single pump, imagine deleting multiple pumps.

 

Your design as given by Daikin, was sound, zero issues. Don't fret about heat pump size, you can run an oversized heat pump with very little impact on CoP, as long as you cycle rate is is ok (especially with UFH), 2 or 3 cycles per hour in mild weather is ok. Run the system in weather compensation without thermostats, should yield a SCoP over 4 easily. Convert buffer to volumiser or delete and get rid of the additional pumps.

 

You have the design, find a plumber to change it for you. 

[JamesPa]

4 hours ago, JamesPa said:

Curious given how different the design is to the one their guy originally specified!  Basically Daikin are therefore saying design doesn't matter much. 

 

 

3 hours ago, JohnMo said:

First if Daikin hold the MCS licence the design has to be installed per your layout at the start of this thread. If the plumber was the MCS licence holder and issued the certificate, they are the designer, not Daikin, Daikin sketch is just that a sketch not a drawing. So you need to get your head around that side of things.

 

So ... IMHO you should carefully note what @JohnMo has said and also note carefully what I have said. 

 

Fundamentally someone is responsible for the design and someone is responsible for executing the design.  They may or may not be the same person.  Finally you have to factor in what you actually agreed to.

 

As @JohnMo says the original design as done by Daikin is sound.  The complications to be aware of are firstly: that may not be what you signed up to (who has the MCS licence) and secondly: is if you agreed (expressly or by implication) to a change.  So you need to think about this.  If you did agree to a change then think about whether you relied on their 'professional advice' (!?) when you did so. If you did agree to the design change and didn't rely on their professional advice then you may not have a leg to stand on, otherwise you could argue that the advice was faulty, but of course that's a matter of (professional) opinion.

 

Unfortunately someone else looking at the system is just another opinion, which you will have to pay for but which can be easily dismissed by the opposition.  Unless there is an agreement upfront to be bound by this opinion, you may struggle to enforce it. 

 

So my recommendation is to rely on contract unless you have no option.  Thus the first call is what did you sign up to and (as @johnmo says) who in what you signed up to has the MCS licence, and what did they say?

 

if the contract is violated then you have a clear case in the small claims court.  They will likely fix it rather than go to court. 

 

If the contract wasn't violated then its one 'expert' vs another in which case its probably best not to waste your money and instead just 'plumb out' the buffer and live with the oversized heat pump. 

 

If, somewhere along the line, you consented relying on their 'professional opinion' then its in between, but probably closer to the latter (ie don't waste your money) than the former.

 

Sorry potentially to be negative, but ultimately what is enforceable is contract and statute (eg building regulations).  Contractors/manufacturers, of ASHPs and everything else in life, know and exploit this - often totally ruthlessly if they don't care about the effect on their reputation.  They also exploit the fact that most people aren't smart enough or dont have the resources to work through the contract/statute, so they take liberties when it suits them .  You need to be equally smart (or smarter) in nailing what they have breached, or be sanguine about it if they haven't breached anything.  

Edited Thursday at 21:28 by JamesPa

[Dillsue]

12 hours ago, JamesPa said:

 Contractors/manufacturers, of ASHPs and everything else in life, know and exploit this - often totally ruthlessly if they don't care about the effect on their reputation.  They also exploit the fact that most people aren't smart enough or dont have the resources to work through the contract/statute, so they take liberties when it suits them .  You need to be equally smart (or smarter) in nailing what they have breached, or be sanguine about it if they haven't breached anything.  

You're right that businesses can behave like that and have unbelievably biased Ts and Cs that they will throw in a customers face and stick 2 fingers up to complaints against them. Fortunately there's a piece of consumer law called the unfair terms in consumer contracts regs that effectively remove unfair terms from a consumer contract thus holding a business accountable if they've not delivered a service they've provided with reasonable care.

 

Once the OP has worked out if he has a single or multiple contracts then anyone trying to hide behind biased Ts and Cs and shirk their responsibilities should be referred to said legislation.......it does work:)

 

It's alway best to resolve things amicably though