@Morgan, you are correct. The installer's job, as per MCS guidance, is that the system is designed, installed and commissioned in keeping with their guidelines. Sadly, this isn't happening consistently, hence the countless forum posts from new members and messages on My Home Farm, and I suspect we'll see many more this winter.

From our experience, the design was about 75% covered, the system was 100% installed with 25% of the design missing (rads not sized correctly, underpowered distribution pumps and even our oil boiler that was retained to be part of our bivalent system was not fully taken into account from a design and commissioning perspective. With pieces to the puzzle missing, systems are commissioned and appear to work, until winter comes and the short fallings become apparent.

Posted by: @batalto

@morgan you can commission it, I just don't think you'll get any installer to dial in a custom heat curve per property. Better to leave simple instructions for the user to tweak themselves. It's not like it's hard - but people need to be informed on the process

Yes and no. It's great that some people like yourself have the ability and desire to tweak and learn about your system, but sadly many people just don't have the time or the inclination. When you pay upwards of £10,000 for a heating system you just want it to work. We paid well over that – we're now entering our third winter and are still tweaking things – if it's not efficiency, it's performance. This, as things stand, is the Achilles heel for heat pumps. Boilers just work. Heat pumps need adjustment periods and a lot of patience.

@dawnrg, I think your system is running hot, and if you're concerned about running costs you're fully entitled to getting the matter resolved and getting the answers you require. From what I have seen, Grant UK are customer service orientated and they do make site visits. I would be persistent and get answers from them.

If you're still not getting anywhere, and if your system was installed by a MCS-accredited installer, I would contact the MCS and see if they have any advice.

I'm afraid that this isn't a quick and easy process. You will have to be patient and persistent.

@editor I think your issue is that the people installing are not engineers. They are (by and large) plumbers - anyone can call himself a heating engineer, it's not a protected term like in Germany. I doubt they understand the finer points of thermodynamics or even the basics. Most will just follow the installation guide supplied which will give you a working system which does what people want - provide heat. I doubt very many will ever take the time to understand the customers house and dial in the settings. Even then, they'll have home owners go and mess with the thermostat because they (the customer) also doesn't understand how the system works.

@editor 

You are all correct to a certain extent.

I have been commissioning industrial systems for more years than I can remember, and have worked on numerous different types of equipment, from different manufacturers, from all around the world. So it comes as second nature to read through the manual and fairly quickly decipher what sections are important and what parameters need to be adjusted. But, whilst I may have been involved with the design, may have overseen the installation and then carried out the commissioning and optimisation, I did not do it all. Its horses for courses as they say.

There would appear to be a profound lack of training within the ASHP installation industry, which I doubt will dramatically change overnight, since training costs money. The larger installers should have an installation team and a commissioning team, similar to industrial projects, which should get the job done quicker, and hopefully leave a happy customer in their wake.

The smaller installation companies would either need to have at least one staff member who could multi-task, or have an arrangement with the ASHP manufacturer to perform the commissioning and optimisation process.

Either way, whoever is doing the commissioning and optimisation, should not only be fully conversant with the equipment, but also have a sound knowledge of the system, and how best efficiency can be achieved.

As Mars has pointed out, there are more and more people coming to the forum, having recently discovered that their heating system is operating at an efficiency of probably 50% or less.

If anyone would genuinely like me to help resolve problems with their system, or advise on how to improve the efficient, would you please direct messages on the forum to me by name. I'm afraid I have spent many hours recently, reading through manuals in the quest to find the answers, only to have simple requests for further information or clarification, or to measure the temperature somewhere completely ignored.

If you genuinely want help, rather than just having a rant on the site, then please be prepared to answer possibly numerous questions or requests, so that I can try to ensure that the information that I provide, is indeed correct for your system and hopefully resolves the problem.

The choice is yours.

@kev-m I obviously have no idea what I am talking about and my assumption that the flow temperature was 52 was based on something the installer said at the annual service.

We have clarified the changes he made at the service. 

Previously the water temperature out of the pump was 52 and ingoing was 44 (difference 8 degrees) now it is 52 and 47 (difference 5 degrees) I think the change was to prevent the temperature dropping so significantly? The service engineer said he was learning all the time with experience and recommended these changes.

Weather compensation is on.

We have certainly noticed that the radiators are much warmer than they were before and the house warms up much quicker when the temperature drops in the house. We use a HIVE thermostat in the hall.

I have measured the temperature of the radiator when it is at its hottest and it is about 30 degrees. Most of the time the radiators are much cooler than this.

For November we used 1184 kwh for all electricity. We use the oven everyday as my son has a special diet so this probably bumps it up.

Overall we are happy as the house is warm and the costs are still just below our oil costs. I love no longer having oil.

I don't want to change any of the settings (too scary) 

BUT I don't like not understanding how this all works and any explanations would be great.

Your thoughts would be appreciated.

Jane

@jane all those settings are is the heat going in the radiators and going back into the pump.

At the moment your pump will kick on, get hot bring everything up to temperature and then turn off. This is the least efficient want to run a heat pump. The most efficient is often and at a low temperature

By lowering the weather compensation you are searching for a point where the pump is producing exactly the same amount of heat as you are naturally losing from the house walls/radiators etc. 

The lower the working temperature, the more efficiently the pump will work; as it costs more to make water hotter. Just tweak the settings down slightly and see how you get on. Little by little. Worst case, just turn them back up!

@jane 

I'm no heating engineer but as far as I understand, the ASHP sends water out at the flow temperature, it circulates round the radiators, emitting (losing) heat and is measured when it comes back (return temperature).  The engineer may have increased the flow; i.e. make the ASHP pump the water round faster.  This would decrease the difference and 5 is better that 8 for an ASHP.  Mine is normally 4-5. 

If the flow is 52 and return is 47 then your radiators will be somewhere in between the two. That's at the upper end for an ASHP and they would feel uncomfortably hot to touch.  You would not want to be running your ASHP like that all the time.  If they really are 30 then perhaps that's the weather compensation working but 30 seems low - is your thermometer definitely reading accurately?   Remember a baby's bath should be 37-38C so 30 won't feel hot to the touch at all.  If you can heat your house with radiators at 30 your ASHP will be running very efficiently.

On my ASHP I can move the weather compensation curve up and down with one button on the main screen.  I don't know if you can do this with yours; you will have to check out the manual. 

Kev