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Air source heat

Every tom dick and harry is installing them at the moment.
Half don't understand what's needed get them to work properly.
Then when they don't work as expected it will cost a fortune to sort it out.
 
dognero said:
Every tom dick and harry is installing them at the moment.
Half don't understand what's needed get them to work properly.
Then when they don't work as expected it will cost a fortune to sort it out.
Click to expand...
Usually they are removed at more expense, I looked at our gas usage and apparently even with standing charges we are just under £400.00 a yr for gas, I don't think it's an economical swap for us at mo, if we got a 4 to 1 ratio there is no way we are only going to pay 100 for electric to heat our house, I'm aware that's not mathematically sound but it's a rough gauge.
 
dognero said:
Every tom dick and harry is installing them at the moment.
Half don't understand what's needed get them to work properly.
Then when they don't work as expected it will cost a fortune to sort it out.
Click to expand...
Similar with LPG conversion. I was booked in to have the job done and got a cautionary message from a member to say that the company wasn't much cop. (Thanks Malcolm) This was at the time when Simon had just joined us and I became convinced that he knew what he was talking about so I cancelled the one I'd booked and Simon did the job. The rest is history.

Octopus Energy make their own pumps. They train their surveyors and installers and they have very good customer service. I've been with them for a few years now and can vouch for this so I have confidence that they will do a good job. I've seen the pump in a real-life setting and got answers to my long list of questions so I'm convinced that the product is OK and that the installers know what they are doing and don't leave a mess.

The survey is booked for Wednesday afternoon 15th Jan and it will all hinge on whether I feel that I can have confidence in what he recommends and that there will not be too much upheaval to install the parts that go inside the house. I realise that there will be some disruption and that it will take three days to install, but I don't want my wife to get upset (she has dementia) so if it's going to be a long, messy job I won't bother unless I can arrange for her to go and stay with one of the kids for a week.
 
Thanks for that Stephen. Do you have a list of which ones are better please?
I like Octopus as a Company, but I'd be happy to go elsewhere if the product is better.
 
George322 said:
Thanks for that Stephen. Do you have a list of which ones are better please?
I like Octopus as a Company, but I'd be happy to go elsewhere if the product is better.
Click to expand...
The best ones surprisingly are made in cold countries like Finland unfortunately, nibe has one with scop of +5 for normal and + 4 for cold 😂 I fear their idea of cold and ours are worlds apart, I'm sure valiant and ideal quote higher numbers than octopus, I often have companies trying to get me into it but I'm at the wrong end of my work life to be getting involved in witchcraft.

I put a little bit more thought into our situation and current use and it would probably be absolutely bonkers on how much we pay gas wise, ours is short bursts when needed, heats up in 20min, to do that with a heat pump is impossible at the mo which would mean much longer run times when it's really cold and when the efficiency is low, I could easily see our our energy use more than doubling, possibly tripling or worse, I can see how folk in our situation talked into it would be going wtf.
 
The Cosy 6 has a SCOP of 3.4 which is below most of the "big name" makes, many of which have a SCOP of 4.5 or higher.
A Vaillant 5kw would be my choice as I've had their gas boilers a couple of times and had very few issues with them, but they cost a lot more than the Cosy 6 does. Including the grant, a Vaillant 5KW would cost me about £3.5k more than a Cosy 6KW.

The big appeal to me is that I could use "free" or cheap electricity from the panels and/or battery to run the pump and I could be gas free.

My inverter has an emergency power supply socket and I 'll get this connected to the main board to power the pump, lights and a couple of sockets if there's a power cut.

Most people who have solar panels can do this but the installers don't tell you that it needs additional wiring etc.
 
@George322 I've been following this thread with some interest as we are going down the ASHP route as well.

We have decided to go for the Cosy 6 as it will fit slightly better than the equivalent Vaillant. We will need to replace all but 2 of our radiators and put one back in that we removed about 20 years ago, the hot water cylinder will also be replaced. I just need to tell Octopus that I'm interested in getting an eddie solar diverter for the new hot water cylinder and get the artex on several walls tested for asbestos and then an installation date can be set.
Our gas supply will be capped as well.

We have 14 solar panels on our roof but don't have a battery.
 
Have you had your survey Colin?
Did you learn anything of interest?
What figures did you get for heat loss?
What size water tank are you getting?
I can definitely recommend getting a battery backup if you can find batteries at a good price, but if you can use any excess power that your panels produce to heat your water it will be a big saving - especially from April to September when you will typically be producing more than you use and can put the air pump into hibernation for a while.
A couple were moving to Australia and had batteries that were less than a year old for sale. I got them for £350 each. Pylontech 2.4's. I now have eight 2.4's. (19.2kWh) This allows me to charge them up when electricity is cheap and use them when it's peak time.
 
@George322 We've had two surveys, three if you include the EPC one.
Our heat loss has come in at 4.6 and 4.5.
We will be getting a 180 litre tank.

I've learnt that similar sized ASHP are not equal, British Gas said they wouldn't put a Daikin unit in but the Vaillant would be OK even though they were rated the same.

SWMBO is coming to terms with losing the airing cupboard both from a drying and storage point of view. She may not have realised that the upstairs is going to lose what is effectively a bloody big radiator, but she does complain about the upstairs being too hot at times.

We don't own or get a feed in tariff from our solar panels, they're not really ours. The installer/owner gets paid for what they generate, we get the benefit of what they generate and the excess goes to the grid. We could have batteries but have never got around to it, haven't considered 2nd hand ones but have seen them in action on TV etc...
 
Our survey was cancelled the day before they were due to do it last Wednesday. It will now happen on Thursday this week. If our heat loss is similar to yours I'll consider a Vaillant 5 Aro therm plus with a SCOP of just over 5. A Cosy 6 with a SCOP of 3.4 would do the job easily but I think it would cost more to run it. If we don't need many radiators swapping, then the Vaillant installation would be about £1k less than I was quoted so it would only be £1.5k more than the Cosy. I'll see what happens on Thursday before deciding.
 
As an aside to the thread, we've had an air to air reversible heat pump fitted with one outdoor unit and three indoor units. The French gov are pushing them as an efficient alternative to oil fired boilers/radiators, which we also have, and are offering grants. One advantage is that they can heat in the winter and cool in the summer. They get pretty warm, even in this below zero weather.

Electricity is the cheapest form of heating here and it's set to get cheaper still in March with a per unit price drop. Gas is by far the most expensive here, either piped town gas or LPG tanks. Pellet burners are becoming popular also, but wood is cheapest and still widely used, as are paraffin heaters. We also have a wood burner but have never used it.

Water heating is done almost exclusively by large electric immersion heater tanks.
 
LeStempy said:
As an aside to the thread, we've had an air to air reversible heat pump fitted with one outdoor unit and three indoor units...
Click to expand...
Another advantage of air to air (versus air to water to radiator setups) is that scop is higher in real world situations. If you want to heat a house using radiators they need to be hotter than the air coming from a blown air vent would need to be to output same heat into the room... Radiators don't do much radiating when their temperature isn't much hotter than the room but a fan heater will still shift a high volume of air and heat it and the output temp doesn't need to be much above the input temp for that to happen.

Apparently French electricity is cheaper than UK electricity because France has an excess of cheap electricity due to more nuclear power stations. France exports electricity to the UK. The UK gets half it's natural gas from UK owned North Sea sources whereas France imports all its natural gas.
 
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LeStempy said:
Yes, lots of nuclear power, unlike Germany who decided against it. There's also a wind turbine on every corner 😁
Click to expand...
And twice as much land per person to build wind farms and solar panels on compared to the UK
 
LeStempy said:
Water heating is done almost exclusively by large electric immersion heater tanks.
Click to expand...
Most hot water systems heat water to 60C. It doesn't need to be at 60C because 60C would be too hot for a shower or sink bowl water but we're used to mixing cold water with hot water for these purposes and if we have a limited supply of hot water such as from a hot water tank heating it to 60C gives more capacity of water at the temp we want it since we mix it with cold water.

If the French don't use heat pumps to heat hot water to 60C maybe they've realised that heat pump scop isn't very good when heating stuff to 60C so its not worth using expensive heat pump setups to heat water to 60C. An obvious workaround would be to heat hot water to 35 or 40C and use it undiluted (not diluted with cold water) for showers and sinks etc. If there were a capacity problem (if the hot water tank is only big enough because its water is normally diluted with cold water for use) the hot water tank could be twice as big so a tank of hot water at 35C would still last as long in use as a smaller tank of hot water at 60C. But even the workaround might not be the best use of heat pump because another factor in this is probably related to the general advise for using heat pumps to keep a house interior warm, the advise being get the house warm and keep it warm without letting temperature change much - The thing about hot water tanks in this respect is that as you use the hot water from the hot water tank it is refilled with cold water, thus cooling the hot water tank a bit like leaving house doors and windows open or turning the heating off when everyone goes out of the house would see inside the house cool down, so the heat pump would be working outside of its ideal conditions (constant internal temperature) much of the time, this again affecting scop.
 
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