Really good episode thanks for that.  Uplifting as well as informative and, dare I say, it giving real hope.

The guy from heat geek (James?), 51 mins in, talks in very strong terms and with reference to other industries, about (lack of) cpd.  A very poignant comment I feel.  I genuinely wonder how many in the industry (by which i mean the construction industry of which heating is, like it or not, a subset and thus influenced by similar attitudes) even recognise the acronym.

What value is mcs adding to the installs by these guys?  If only someone had asked that question!

A very interesting episode, and it was good to hear a constructive discussion from a group of contributors who are rivals within the same space.

One thing that cropped up which I can absolutely attest to is Clayton's (EDF) point about wanting customers to get a heat pump installed, even if it's not through their company.  I experienced this during my quotation gathering process and words to that effect were spoken by my points of contact at both Octopus and EDF.  Octopus went as far as giving permission for their plans and radiator schedules from their survey to be shared with other potential quote providers (which ultimately assisted with the information gathering process, and enabled a better quality of conversation all round).  I didn't ask for this, and it arose from my telling them that I had no intention of sharing their work elsewhere, at which point he said he was happy for us to do so.

EDF, through CB Heating, also went above and beyond with regard to trying to find a workable solution for the design challenge we had, which was a sizeable 30 year-old polycarbonate conservatory which was already on the wet heating system, albeit controlled by a separate thermostat to the rest of the house.  Having been unaware at the outset at quite what a challenge this room would prove to be in the overall process, their approach was refreshing.

Ultimately, I ensured that I fed back to both points of contact that I had gone ahead with an installation, which is an unusual step to take in a competitive quotation process.  I'm not sure a "Yeah mate, I'm really happy with the installation done by someone else, and thought you should know this" conversation would work in any other scenario, but both were very positive conversations to acknowledge that each of them had ultimately helped to get me to the point of committing to a heat pump installation via my interactions with them.

There's a really interesting point made by Thomas from Octopus at around 38:45 in the video where he's talking about methods of heat pump running, essentially between a WC low and slow methodology and the internal thermostat driven method used by the Cosy pumps, and references 'SCOP chasing' vs actual cost to the user.

The biggest surprise I've experienced since having my heat pump installed is the amount of time that Havenwise has it sitting idle during the day whilst running a thermostat driven internal temperature requirement 24/7 in the house.  Ultimately the experience of this to date is that the COP is lower than I could perhaps achieve via running it on pure weather compensation, but that the cost savings so far, relative to gas central heating at the same time last year, are proving to be significant.  If that's ultimately achieved by a heat pump running at a heating COP of just over 3, but doing so sitting idle for 50% of the day (which is how the Havenwise control appears to be driving it) then that's the 'right outcome' for me as a homeowner, relative to a system that might run 24/7 on WC at a COP of 5.0 but which ultimately costs more to heat the home.

Posted by: @sheriff-fatman

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The biggest surprise I've experienced since having my heat pump installed is the amount of time that Havenwise has it sitting idle during the day whilst running a thermostat driven internal temperature requirement 24/7 in the house

My strong suspicion is that if a heat pump would otherwise cycle, particularly if it would otherwise cycle with short on time, then setting it to idle for some of the time to force longer on times could well be beneficial.  It's cycling anyway, so the question becomes, how to cycle it most efficiently.  Without something like havenwise then you are reliant on the heat pump default settings which may or may not suit your house, particularly if the heat pump is well oversized.

I would be surprised if forcing it to idle  when otherwise it would not cycle is good for cost (in the absence of a tou tarrif of course) but it would be interesting to compare what havenwise does when it's very cold with what it does when it's mild to see if they have found different in the real world.  Examining what they do may well teach us how to run oversized heat pumps better (and doubtless other things)!

It is an excellent discussion and I'm glad everyone focussed on the positives.  Thanks for asking my question @editor I appreciate that.  This is the comment I've added in youTube:

"I'd have to agree with TJ from Octopus that cost of operation and not SCOP is really the important factor in heating the home. He does talk about the Primary Pod being the thermostatic method for calling for heat when the house needs it, and turning that heat off when it doesn't. Clearly there will be hysteresis around that temperature point and I think that gets to the nub here: the phrase "when the home needs it" is a bit misleading, because it is really "when the area in which the Primary Pod sits needs it." In other words, the heating of the whole home is dependent upon the heat loss of the area where that Pod is. When the heat goes off, rooms with a higher heat loss will slowly drop temperature; conversely, rooms with a lower heat loss with slowly increase in temperature. This might work better if the system design were to a common temperature (i.e. every room designed to 21c or 22c) because you take account of differing heat losses and thus maintain the same temperature everywhere. Design though is actually to the MCS guidelines so differing temps in differing rooms. In this situation, radiator balancing isn't an answer (I don't think, perhaps someone can correct me) because the radiator sizes are not "equal" to delivering the same temperature as the area with the Primary Pod. Positioning that pod then becomes critical to minimise the issue of differing heat losses but that's not really solving the problem here, it is just (hopefully) minimising it. The best place for the Primary Pod in my house is the living room because of (a) the radiator design to MCS guidelines and (b) the heat loss in other rooms. If I set the target temp to 22c, hysteresis will raise it to 22.3c but just two people can add an extra 0.2c plus of course any temp gain from TVs, satellite receivers, sound bar etc. So until, and unless, the heat loss drops the room by 0.6c heat stays off all over the house - a couple of my rooms were dropping to low 17c and low 18c even at an outside temperature of 9.2c (design is for these rooms to be 18c at -3.2c). Conversely at the same time many other rooms were running at over 23c, some close to 24c. This isn't particularly cosy to be honest but I don't know what the answer is."

A bit long again 😀 Obviously, I have the other thread going on where I'm trying to get some data on running it on WC alone.  I think once I have it stabilised as best I can with that method, I may try reverting to thermostat control and collecting comparison data - won't be truly comparable as I can't control the OAT but I do have reams of data now so I might be able to compare Input kW. 

Posted by: @jamespa

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My strong suspicion is that if a heat pump would otherwise cycle, particularly if it would otherwise cycle with short on time, then setting it to idle for some of the time to force longer on times could well be beneficial.  It's cycling anyway, so the question becomes, how to cycle it most efficiently.  Without something like havenwise then you are reliant on the heat pump default settings which may or may not suit your house, particularly if the heat pump is well oversized.

I would be surprised if forcing it to idle  when otherwise it would not cycle is good for cost (in the absence of a tou tarrif of course) but it would be interesting to compare what havenwise does when it's very cold with what it does when it's mild to see if they have found different in the real world.  Examining what they do may well teach us how to run oversized heat pumps better (and doubtless other things)!

I've got some additional insight into this via the recent sources of data capture from the heat pump that I'm now able to analyse, and which finally overcome the limitations of what MelCloud provides as user data.  I'd been meaning to update my original installation diary thread to provide a running post-installation 'blog' of how the system is working, so I'll provide some analysis within that.  I have to admit that I'm fascinated at seeing the usage data after the 'phoney war' of the immediate post-installation period when it was simply providing hot water.

From what I can see, the Havenwise approach to my particular system is very similar to that which Thomas describes for the Cosy Heat Pumps.  It's thermostat driven from whichever room the Ecodan thermostat is placed (and one adjustment I've made has been to relocate this to reduce some rooms slightly overheating when driven from the originally recommended location).  The system just calls for heat to maintain the desired temperature when it requires it and sits idle for the rest of the time, unless it's doing a hot water re-heat.  In recent days it's also now started to do anti-freeze cycles and there are also now some periodic defrost operations taking place in the current temperatures, so the usage has increased. 

Its probably why that particular section of the video where Thomas discussed this resonated so much with me, as it describes the heat pump operation mode that I'm experiencing and, based on the energy cost analysis so far, the savings are suggesting that it's proving effective.

Posted by: @sheriff-fatman

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It's thermostat driven from whichever room the Ecodan thermostat is placed

So is the flow temp changing as well or is that fixed?

Posted by: @jamespa

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So is the flow temp changing as well or is that fixed?

From what I can see it's being operated in fixed flow temperature mode, but Havenwise is dynamically changing the flow temperature requirements to deliver the bursts of heat, and doing so far more frequently than could be replicated manually.

Posted by: @sheriff-fatman

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Posted by: @jamespa

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So is the flow temp changing as well or is that fixed?

From what I can see it's being operated in fixed flow temperature mode, but Havenwise is dynamically changing the flow temperature requirements to deliver the bursts of heat, and doing so far more frequently than could be replicated manually.

 

I think that's what they do, so they are varying ft.

It would be good to see some plots at various oat values

Posted by: @jamespa

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The guy from heat geek (James?), 51 mins in, talks in very strong terms and with reference to other industries, about (lack of) cpd.  A very poignant comment I feel.  I genuinely wonder how many in the industry (by which i mean the construction industry of which heating is, like it or not, a subset and thus influenced by similar attitudes) even recognise the acronym.

That was Aadil from Heat Geek, and yes, his point about CPD was valid. I thought that too.

I completely agree with you: in so many parts of construction, ongoing professional development is either non-existent or treated like a box-ticking exercise. Heating is unfortunately no exception, even though the systems we’re dealing with now are far more complex than the boilers of the ‘90s.

On that note, I was recently sent the course that’s used for low-temperature heating installs. And while it’s well-intentioned, it’s basically a textbook version of what we already discuss here daily… all the design theory, delta-Ts, emitter sizing, heat loss values, pipework dynamics and so on, but turned into 220+ pages of formulas and maths that, frankly, most installers don’t use in the real world.

We can have all the theory in the world, but unless there’s a culture of continuous learning (and accountability), we’re going to keep seeing the same design and commissioning failures turning up here on the forums.

Posted by: @jamespa

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What value is mcs adding to the installs by these guys?  If only someone had asked that question!

We ran out time so quickly. These guys would not have thrown MCS under the bus publicly though (I don’t think)… and for them MCS equates to £7,500 per job.

Posted by: @editor

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On that note, I was recently sent the course that’s used for low-temperature heating installs. And while it’s well-intentioned, it’s basically a textbook version of what we already discuss here daily… all the design theory, delta-Ts, emitter sizing, heat loss values, pipework dynamics and so on, but turned into 220+ pages of formulas and maths that, frankly, most installers don’t use in the real world.

We can have all the theory in the world, but unless there’s a culture of continuous learning (and accountability), we’re going to keep seeing the same design and commissioning failures turning up here on the forums.

I agree with all of that.  220 pages is perhaps 210-215 pages too much.  Unfortunately there is no substitute for (a) understanding some basics (which does NOT require 220 pages) and (b) using that understanding to think about the problem (c)  working through some practical examples and then discussing it.  I fear many people in the business are not used to any of those, and rigid rules hinder rather than help.  The best education might be to join this forum!

Whatever the reason it seems clear that useful CPD is sadly lacking otherwise the same mistakes wouldn't be made repeatedly.