Hello everyone!

I'm getting a new house built just now in the north of Scotland and it will have an ASHP plus some solar panels. I could do with some advice along the way and this forum looks like it be helpful.

@dodgyknee Welcome! Always great to have another Solar PV/ASHP acolyte- they’re a great combo. We’re here to help for any advice on either 👍

I have just recently May 2nd had an 8.5KW Mitsubishi Ecodan ASHP and radiators etc fitted to my 1960s bungalow in the Cairngorms. Courtesy of Moray Council and Home Energy Scotland. I have not been able to afford solar panels but I am still expecting to save money, because I had old storage heaters, using 14000kWh per annum previously in total. In winter, I would use 50-60kWh a day. But the day before fitting the pump I used 40kWh, now I am averaging 6-9kWh a day in total. I know this will soar in our winters here where the temperature hits -15 on occasions. But I still suspect that Hiroheater (see pic) will not consume more than my old storage heaters did. I am now firmly in the University of Air Source Heat Pump phase. This is a good forum.

Hoping to find answers to all the questions that I have. And there are many. The day the installers (Everwarm) left, I asked about the FTC6 control unit, they said, best not touch it….. But I am not that kind of person…..

Posted by: @amanda1

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The day the installers (Everwarm) left, I asked about the FTC6 control unit, they said, best not touch it…..

That's interesting 'advice' @amanda1

May I compare that comment from your installers with the requirements of the Building Regulations, Part-L, section-9

Part-L has recently been upgraded. Section-9 goes on to describe other requirements to comply with the legislation including a new SAP-test for energy efficiency.

It is the responsibility of the Installer to ensure that the householder can operate and maintain the heating system so as to minimise the energy required for it to run.

Mitsubishi's FTC6 controller is relatively new 

It has the capability to be integrated into a Smart Grid, and to operate alongside hot-water storage vessels from 3rd parties.

@transparent 😂😂😂 They did leave the Mitsubishi manuals, all of them - installation manuals and user manuals. Nicely wrapped in cellophane. The most important one, the one that tells you how to access the FTC6 controller menus, was left next to the cylinder and FTC unit. These are in a cupboard at the outside rear of the house. So I didn’t discover that manual straight away. They did give me instructions on how to use the indoor control unit and I recorded this discussion on my ipad. But no information about what each of the components did. No instruction as to how to locate the wifi interface thing so that I could get Melcloud up and running (not that Melcloud is much use). I also don’t have any documentation whatsoever for guarantee purposes yet, and they omitted to leave an emergency contact number. So I called them to say I needed the manual for the FTC, and they told me they didn’t usually leave much info because they didn’t want call backs when people started messing around with the settings. They did then send someone out and he set up Melcloud for me abd explained a bit more. 

To be fair to them, they were efficient and very quick and I think it’s set up OK, although it’s on default settings for the most part except for Legionella (which I altered) and Freeze Stat function (which is deactivated. The default minimum is 3 degrees. It would be on all the time between November and April if it were set at 3 degrees. My neighbour’s identical system froze up once last winter when the temperature hit -15 and she defrosted it with hot water….which is probably dangerous…)

And it hasn’t cost me anything, it is all on a grant, and I am quite sure that any explanation they would have given me verbally would not have been adequate for me. I like to have things in print. This thing is complicated and I need time to get my head around it, and it is summer so I am still in the honeymoon period because the temperatures are in the 20s. And my priorities with the system are very different from some other newbies - I only have electricity, no access to gas, old storage heaters, etc - so I am used to sky high electricity bills, cold rooms and limited hot water…And I don’t have a massive loan to repay, so my main priority is that it is cheaper if possible and no more costly at worst than what I had before, and that it does provide heat to 19C and hot water. And now my house can get an EPC rating higher than E.

The FTC6 controller has a big downside - it doesn’t include the Energy Consumption and Delivery stats. Melcloud is useless on this front. I take meter readings daily so I know how much electricity is being used daily, in total. 

Posted by: @amanda1

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And it hasn’t cost me anything, it is all on a grant,

Ah... if only that were indicative of the actual cost of ownership!

Over the expected lifetime of a heat-pump, the running costs will easily exceed the capital cost of the hardware and its installation.

The Dept of Business, Energy and Industrial Services (BEIS) spent £14.5m on a 100% funded trial, installing 742 heap-pumps.
You can read the report compiled by the Energy Catapult.

All of those heat-pumps were free.
Yet the majority of those households ended up paying more for their energy than before, even though £4000 of fabric upgrades (insulation) was also utilised per property.

That Trial preceded the energy-crisis of 2022, and electricity was costing around 4-times that of gas per kWh.

So it's very odd that the authors have chosen the strapline "Heat pumps shown to be three times more efficient than gas boilers". 🤔

The key to your heat pump being a success is how well it can be configured to best use every watt you feed it.
Poorly-installed pipe insulation and start/stop cycling are your worst enemies.

Posted by: @amanda1

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And now my house can get an EPC rating higher than E.

If the installers were complying with Part-L of the regulations, then you will know this.

You must have been provided with the results of a SAP score amongst your paperwork!

You should typically be achieving a high-C.
If not, then start looking at insulation levels, draughts and damp before autumn arrives.

@transparent Hi thanks for your comments. I think it is set up OK. I prefer the constant (Normal) setting rather than having timed settings. For info: As far as I have so far ascertained, the Ecodan is running in Auto Adaptive mode, Room temperature controlled. It is on 24/7 but DHW is taking 15 hours to fall to 40 degrees so the ASHP is not kicking in much. Flow temperatures are low. Legionella settings every 15 days to 60 for 1 hour during off peak hours, holding for 5 minutes. It accounts for about 3-6kWh a day usage. I require a room temperature of about 18 degrees, never varying it by more than half a degree up or down, but when I do want it to give heat, it does, quite quickly, and the hot water is always there, always between 40 and 50 degrees, and because it is not on a timer, the pump is not having to heat the water from cold every time I require it. This is important in winter. 

As per my reply to you, it has cost me nothing to have this system installed. If I had not had this system installed, I would still have had my old storage heaters. I would have consumed a total of 140,000 KWh over the next ten years. They were costing me up to £2500 a year for the last ten years, in the last two years, £2800 and then £2400 respectively. My 2 yr fixed rate ends in September and thus from September based on current tariffs on offer and many worst case scenario calculations on my part,  I would be paying £3500 to £4500 per annum at least for the next year. I doubt that prices will come down to the level of my present tariff - that would be unlikely, where tariffs are concerned what goes up rarely comes down. So with or without the ASHP and the associated insulation that I have and am getting, I would still be paying very large amounts of money for heating my home. I am fairly confident based on all the information I have looked at online, and all the horror stories in forums, that the ASHP is not going to cost me more to run than my previous system. Therefore, the installation of the ASHP WILL have cost me nothing. I am fully aware that they use a lot of KWh in winter, but I am betting that it will not use more than my storage heaters did.

My neighbour had the same installation last year and has come through the winter with bills much lower than previously. 

I only had it fitted on May 2nd, and have not had an EPC done since then, and as I said in my reply, I have received no paperwork at all as yet. But they did an insulation and draught survey etc, and I do have the ASHP, and the cavity wall insulation is being replaced tomorrow,  and I already had the loft insulation. 

Basically this scheme covers council tenants and a limited number of owner occupiers who apply for it, and I suspect that the contractors are treating all installations as council properties and with that comes an immense amount of high handedness - but that’s only a theory. 

Posted by: @transparent

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So it's very odd that the authors have chosen the strapline "Heat pumps shown to be three times more efficient than gas boilers".

At the risk of sounding like a stuck record, this is is so important, that it bears repeating.

In raw terms, heat pumps are about three times more efficient (or more) than gas boilers, which is why this heat pump propaganda/marketing bullshit is allowed, but it only translates into costing three times less to run if you ran your gas boiler exactly as you run your heat pump ie on all day, which of course most people don't. The reality is that installing a heat pump forces you, because its output it is relatively feeble, to run your heating in an extremely expensive way, ie on all day, and the extra costs can easily cancel out any efficiency savings.

To use a tired cliche, this is one of the elephants in the heat pump room. 

@cathodeRay

Posted by: @cathoderay

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In raw terms, heat pumps are about three times more efficient (or more) than gas boilers, which is why this heat pump propaganda/marketing bullshit is allowed, but it only translates into costing three times less to run if you ran your gas boiler exactly as you run your heat pump ie on all day, which of course most people don't. The reality is that installing a heat pump forces you, because its output it is relatively feeble, to run your heating in an extremely expensive way, ie on all day, and the extra costs can easily cancel out any efficiency savings.

I really cant agree with this statement for the reasons I will outline below, but in a practical terms I have self installed two heat pumps and both installations have provided me with a very cheap to run heating system, albeit coupled with solar panels

The quoted 3x figure is in terms of kWh so whether you push the required kWh into your house quickly (with a gas boiler) or slowly (with a heat pump), it is still 3x more efficient. If the price differential between gas and electricity is 3, then the two system will cost exactly the same to run.

Or are you saying that you need more kWh with a heat pump than with a gas boiler because you run it overnight? Personally I dont run mine overnight and in a well insulated house you dont even have to run it all day (In my last self build I only had two heating slots morning and afternoon). Coupled with this is the possibility of cheaper tariffs overnight and the thermal mass of the house releasing the stored heat back during the day when electricity is more expensive.

In addition recent advice during the energy crisis was to run your condensing gas boiler at the lowest temperature you could to improve its effiency, which I did and at the same time tested how low a heating temperature I could utilise when I installed my heat pump. And yes I ran the gas boiler all day 🙂

@cathoderay And another stuck record would like to remind you that we are comparing apples with rabbits until we have parity for energy prices per kW/h., different fuels and costs makes a mockery of comparing real costs of running any heating system with others. If a kW/h. of gas, electricity, oil, wood pellets etc. were all equal, heat pumps would be everyone’s favourite! Whilst gas is subsidised or electricity carries additional levies above those imposed on gas, then price differentials work against the employment of common sense! Regards, Toodles.

@cathoderay Both you and @transparent do indeed sound like stuck records….you obviously have big negative axes to grind on ASHPs. I am very well informed on the potential pitfalls of ASHPs. I am not sure why @transparent and you have both piled in on my introduction post specifically. I came on this forum for the more helpful information it contains from other ‘noble’ members, on things like Flow Temperature, Weather Compensation Curve etc etc etc, rather than this basic let’s not even get off the ground meh about them being more costly etc etc etc. This is a ‘renewable heating hub’. Not a ‘don’t get renewable heating’ hub.

@toodles I am comparing apples with apples because I live in a place where we do not have access to the gas grid. I am comparing my electricity KWhs usage with storage heaters to my anticipated kWhs usage with an ASHP. Many of the people who complain about the expensiveness of ASHPs seem to have been previously enjoying the benefits of gas central heating….