Posted by: @morgan

@siko thanks for a very informative and interesting summary of your install. My install is ongoing right now (we’re at day 3) and, so far, not nearly as dramatic or traumatic as your experience . I was hoping for completion tomorrow but looking more like Wednesday 🙄

Thanks Morgan - glad you found it useful! Yes it has been traumatic but I always thought it would be and compared to what I thought it might have been, I consider myself very lucky sofar 🙂 I am just happy to have a working (if potentially expensive - we shall see of course..) heating system at last and a provisionally agreed RHI.

Few points I forgot - the total cost with all the extra bits and bobs was circa £16k which sounds a lot, but I would estimate there was at least 2 weeks worth of work there for an average of 2 people, so I think I got my money's worth. The work of stripping out the old system was a day in itself and then another day was spent removing old valves and electrical kit that was scattered around the house, removing old pipework from the log burners etc. The work has in general been completed to a very good standard and the problems we encountered were mostly due to the company being extremely busy and the old left hand/right hand communication issues. With the RHI payments we have got the old system removed and a new system installed for a net cost of £5k, which I think is bloody brilliant. The plumbers who looked at fitting an oil boiler (if it could be done - long story) were looking at about £7k with groundworks, oil tanks, piping etc for a legacy system.

I know I work for the oil industry and should have gone with oil, but I'm pretty chuffed that we are no longer burning 15 tonnes of wood pa (we'll still use our logburners of course but vastly less) and that the energy to power our house is 100% renewable.

Forgot to mention about draughts - because we have two massive log burners we had a huge amount of airbricks and also our window/doors weren't fitted that well leaving lots of small draughts. No issue when you have massive logburners roaring away and just got a bit draughty/cold if the fires were off or if we had been out of the house. I knew that it needing sorting with the ASHP and bought a load of brush sealant strips off Amazon (£25 or so total) and sealed the doors and windows; I have also put closing vents on most of the air bricks which were wide open 24/7 before (some of them 5" across). This has made a massive difference too and the house stays warm for much longer than it did before, as we have Velux windows and lots of glass it warms up really quickly when the sun is out too - so if you haven't checked for draughts then please do so and seal them up.

Final point - noise. We were really worried about the noise as we live in the middle of nowhere and it is very quiet indeed, but it really is no issue at all and at worst sounds like a fan heater. When it is going flatout you can hear it from maybe 5-10m worst case but it is not intrusive. The only airbrick I have left fully open is in our lounge and is about 1m from the ASHP and about 2m from my favourite armchair. Does it bother me? Not in the slightest - yes you can hear it when it starts but it just becomes a low noise in the distance that you can quickly ignore. I doubt many users sit as close to an ASHP as I do with the open airbrick and it genuinely is no bother. In fact I find myself sometimes wondering if it is even on when we have put the heating on and go outside to check!

So - first impressions are brilliant, longterm I am very much eyes open especially with electricity prices and will give an honest appraisal here....

@siko 

Thank you for taking the time to post your experience, I must confess to waiting for your updates in a ‘box set binge’ fashion.
It really does mirror conversations I was having with industry last week about the capability of installers having to improve to give a better customer experience through out the process. 

Posted by: @mattengineer

@siko 

Thank you for taking the time to post your experience, I must confess to waiting for your updates in a ‘box set binge’ fashion.
It really does mirror conversations I was having with industry last week about the capability of installers having to improve to give a better customer experience through out the process. 

Thanks mate glad it was useful to you...I think the key to it all is getting a good installer. I was out with some friends when we had just ordered our system and a mate was telling me about his GSHP installation and that he was using a company everyone at work recommended - yes it was the same company. There is a company near me that is MCS accredited and thankfully never replied to email/phonecalls, nice website and MCS accredited but driving past the area one day I found that the business was located in an end terrace house. Nothing wrong with that of course and my dad started his business at home too many years back, but all the minor issues that were quickly sorted out with mine would no doubt have become huge problems if I couldn't have got hold of a one man band outfit. So, it is very much worth going for an established installer with a decent 'footprint' rather than a one man band.

Hi Siko,

I am pleased to hear that all your problems have been resolved and you are happy with your system.

I was a little surprised by the location of your heat pump, since they do need adequate space for free air flow. I would suggest that you carry out a simple test, measure the air temperature at the rear of your ASHP (with it running of course) and compare this with the ambient air temperature measured elsewhere. If there is a large difference it could be that the cold air being exhausted by your heat pump is being drawn into the intake. The efficiency of ASHP's is greatly affected by the temperature of the air being drawn into them, it being their fuel source, so the lower the air temperature, the harder the heat pump has to work. It is better to resolve any possible problem now, before we get fully into the heating season.

Thanks Derek will try that...I did ask the installers and I remember one of Mars' early videos on his setup where he mentions needing 1m around the pump. Obviously the front of the pump faces out into the open and is unobstructed and the back has probably 2/3m onto the wall. The installers said it could be moved if it was an issue as it is only mounted on rubber blocks (very secure though). I don't doubt what you are saying but there appear to be heaps of ASHPs mounted on walls etc with obviously much less space to the rear than ours.

Edit: maybe it's the back that faces out as you get a blast of cold air when you walk past when it's on! Either way it blows freely out into the ether...

@siko, great write up!  Ours was very straightforward in comparison.  The cold air definitely blows out the front in your set up.  Most ASHPs are close to the wall and some mounted on the wall. Ours is about 300mm from the wall.  I think @derek-m is referring the the air flow around the front and sides.  

Posted by: @kev-m

@siko, great write up!  Ours was very straightforward in comparison.  The cold air definitely blows out the front in your set up.  Most ASHPs are close to the wall and some mounted on the wall. Ours is about 300mm from the wall.  I think @derek-m is referring the the air flow around the front and sides.  

Thanks Kev! Yeah it's definitely blowing the cold air out the front where it is totally unobstructed to the western hemisphere - hopefully that's ok.

@siko Hi Siko,

ASHP's require quite a large quantity of air from which to extract heat energy, the colder the air, the more of it that is required and the harder the heat pump has to work. Whilst ASHP's can be mounted fairly close to walls, it is important that there are no restrictions to the air flow at the sides and above the rear of the heat pump. It is also important that the exhausted air can quickly dissipate into the atmosphere at the front of the heat pump, and not be drawn back in at the rear.

Because your heat pump is located within your old wood store, much of the air required will be drawn in through the opening, so some of it could be the cold air being exhausted from the front of the ASHP. It could be that your system is fine, but it is always best to be certain.

Not sure if I'm writing this in the right place so apologies if not! We are at the stage if having an accepted quote and just about to take the plunge. 4 bed large ish detached house fairly well insulated. Replacing an old oil boiler but keeping oil aga. 14kw mitsubishi pump is recommended by installers

However, terrified about I guess the normal things namely;

Electricity consumption ...... this is a really worrying thing for me as pump figures quote 5900kwh per year plus our normal usage 

Actual ability to warm the house, although still have aga and one wood burning stove

Noise of the pump

Can you update running costs at all? I think our house is possibly fairly similar 

Posted by: @cally-m

Not sure if I'm writing this in the right place so apologies if not! We are at the stage if having an accepted quote and just about to take the plunge. 4 bed large ish detached house fairly well insulated. Replacing an old oil boiler but keeping oil aga. 14kw mitsubishi pump is recommended by installers

However, terrified about I guess the normal things namely;

Electricity consumption ...... this is a really worrying thing for me as pump figures quote 5900kwh per year plus our normal usage 

Actual ability to warm the house, although still have aga and one wood burning stove

Noise of the pump

Can you update running costs at all? I think our house is possibly fairly similar 

---

 

Hi Cally,

Not a huge amount to update given our Sep costs are fully explained earlier (524kwh total elec usage=£103), have read the meters yesterday and we have used about 500kwh so far this month putting us on track for 1000kwh in Oct. Our house is 210m2 and EPC E due to the previous log burning system, our yearly heat and hot water requirements are predicted as a frankly ridiculous 24,000kwh which I think is a gross exaggeration (I hope lol).

Our Oct usage sounds a lot but we have had the heating on for a few hours every night and my son was sick all this week so again have had heating on for 3hours at least every morning too. Further to that, we are what I would suggest as a busy family, heavy users of electricity anyway-the washing machine, dishwasher and tumble dryer are almost permanently on and I have been working from home for 3 weeks with a high power usage too. But so far we are using only a bit more electricity than we did before, which is really very impressive.

Noise really is not a concern and it really is not intrusive, in fact it’s something that has been a pleasant surprise and you quickly get used to.

in terms of how warm the house is it’s a funny old one, we’ve set the thermostats pretty much everywhere relatively low to 17-19c dependent on how much we use the rooms. It does take a while to heat them and advice from a friend in the North of Scotland with an ASHP was to anticipate cold weather and turn it up early. This seems sensible and the other bit of advice I got was to help the heat pump out with the logburner on really cold days. So we have a stack of logs ready to go but haven’t burnt a single one yet - because the house is fine and still pleasantly warm even on moderate heat settings. Our system with UFH seems to lag a bit as you might expect, so you set the thermostats to 20c say and the UFH comes on and switches off at 20c, but obviously the UFH is still warm so it climbs a degree or so to 21c. 

It does take a bit of getting used to as rather than a blazing hot radiator from a gas boiler, you get a low warmth from the UFH but it’s like a constant low level warmth everywhere. The floors aren’t anything other than lukewarm to the touch but it’s nice and surpisingly effective. The house just seems pleasantly warm pretty much everywhere and I know we’ll be using heaps of electricity soon enough, but sofar has been very very reasonable. My plan is just to leave the thermostats at 17-19 and use the logburners in the evenings when it’s cold, my boss has a much larger but similar style house than me also with an ASHP and told me has averaged £2k electricity pa but burns around 6tonnes of logs. Again he lives in the north of Scotland and deals with some very cold winters, whilst 6 tonnes sounds a lot, his house is about 30% bigger than mine and a tonne of logs is about £100 or so where I live, so over a winter it’s not unreasonable. We’ve upped our DD with Octopus to £250/month, but I might expect more like £350 in the depths of winter, with around £100/month for the spring/summer months I’m guesstimating about £2400pa or £200/month on average.

Could be rubbish of course but watch this space 🙂

Think it should be obvious but all the prices quoted are total elec bills rathe then just for the ASHP. As an example the previous owners of our house were a retired couple who had an £80/month DD for all their elec use (I know because the Elec company told me what to set mine at). We have averaged about £115/month before the ASHP. So I’d argue we are a high power usage customer but I guess that comes with a busy family, teenagers, Xbox etc….

I've just checked and so far this month we've bought used 285kw; this includes battery charge at a cheap rate, but we would be buying that energy anyway!

Looking at purchased power, Saturday we bought 24kw and the house is a balmy 21 (wife and baby). So far no complaints with the ASHP. We are an EPC A house with heating/hot water demand estimated at 23,000 kw