[Fastterry]

The story of our heating system. The house is now ten years old, 2 bedroomed bungalow, large reception room, and kitchen, with two bathrooms. External walls 100mm concrete block work, finished in silicone render, 50mm cavity, internal walling 150mm timber framing, with solid insulation, 25mm service duct, with 25mm solid insulation over all cold bridges, finish in 12.5mm plasterboard skim coated.
All windows UPVC triple glazed.

Roofing timbers, double hipped roof trusses @ 600mm centres, 40 degree pitch, with19mm sarking, covered with moisture resistant breathable membrane, tiled over with concrete tiles. All roof void insulated with 260mm fibre wool, ceiling 12.5mm plasterboard skim coated.

Flooring, concrete block and beam suspended, floor insulated with 100mm ridged insulation, upnor underfloor heating, with 7no room stats, total area 127m2. Heating from Bosch 25kw oil fired greenstar boiler. This was ran for just over 6 years, with very high running costs, so after studying the ASHP route as an early replacement for the Oil fired boiler, we opted for a 7Kw Vaillant ASHP, this to save money and reduce our carbon emissions.

U values, external walls 0.16, Floor 0.12, Roof 0.15, Openings 0.82 all average
Sap rating 91B Co2 Emmisions, 84B Environmental.


The replacement work started in September 2023, all the work was completed in 4days by Optimum Heating and Renewables Ltd.
The work included, removal of the oil storage tank, replacing the existing hotwater storage cylinder, removal of the Oil boiler and flues, together with all the WiFi controls. The original underfloor pipework has been left in place, this was fully flushed, and reconnected to the new Vaillant ASHP, with a set of hard wired controls. None of the superstructure was altered, so the U values remain the same.

A new Energy Performance Certificate (EPC) was produced, the energy efficiency rating is still 91B exactly as before, but the Environment impact has risen to 92 A.

This does not fairly represent the actual savings on the running costs, which have been more than halved. The system now provides clean comfortable living conditions, no smells, no sharp rises in room temperatures, and no running noise at all.

For us definitely a good move.

[meldrewreborn]

@Fastterry

This is interesting! Thank you for posting.

Why were the running costs of the oil fired boiler high, and what do you mean by high, as people's perceptions differ. The ASHP is clearly delivering for you, so what are the running costs now?

The EPC regime is fundamentally flawed and your experience merely confirms what others have said in the past. Currently the EPC rewards cheaper fuels, not carbon emissions - even so if your costs have substantially diminished the EPC rating hasn't reflected that.

Are you able to disclose what was the net cost to you (after deducting any grants) of the ASHP installation , and how long do you think it will be before you break even?

[Fastterry]

The price of heating oil fluctuates, when our oil fired boiler was removed, it was 0.61 per litre. today it is 0.95 per litre, our annual consumption was 1800 litres, for heating and hot water. Year one £1152.90, inc VAT, Year two, £1304.10 inc VAT, Year three, £1417.50 inc VAT. Servicing the boiler three times £470.00 This doesn’t include the cost of electricity to run the boiler, and controls, that I couldn’t monitor separately. My contribution towards the installation was £3245.00. My total running costs for the ASHP are difficult to assess precisely, partly because we run an EV and most of our electricity is now being billed on night rates, we also have a 4KW array of solar panels, on top of this our Smart Meter isn’t functioning properly. It’s booked in for replacement, once that’s been completed by E-On they will be able to bring my billing right up to date. That’s why I stated the ASHP is less costly to run than the oil fired boiler we removed.

Regarding EPCs these are very misleading and confusing to some people, as they cannot get their heads around the fact that your Environmental Impact rating rises, while your Energy Efficiency rating drops on the EPC, when you swap from an oil fired boiler to ASHP.

I do know from the daily records I keep, right now we are saving money using the ASHP.

[meldrewreborn]

@Fastterry

your heating and hot water costs using the oil boiler were astronomical! Much higher than I would have thought for a 2 bed bungalow of modern construction.

Your set up is quite complex compared to most. Does the availability of cheaper electricity at night influence how you run the heat pump in winter. My gas boiler is off at night because there is no point in heating the home while we’re tucked up in bed and our fuel cost is the same day and night, But running the heat pump at night (or early morning) would bring benefits to you.

[Indyk_EONNext]

Hey there 👋 @Fastterry

Firstly thank you for sharing such an incredibly detailed journey! It's great to know the change has really made a difference for you, by reducing your annual consumption. It really does seem that heat pumps are becoming more and more popular, providing great benefits. We also had another member @P962c share their journey 5 year journey living with an Air Source Heat Pump

I hope all goes well with your smart meter appointment, please keep us posted with any updates! 😊

[Fastterry]

Smart meter replace at the appointed time. This one uses 4G and searches automatically for the best signal available in the area., at the push of one button, it scrolls through, date, total consumption, rate one, and rate 2. The IHD is also a great improvement on the previous one. Thank you E-on

[meldrewreborn]

@Fastterry

Another forum member in west wales who used heating oil (actually aviation fuel) reckoned that heating by oil was the cheapest fuel - even cheaper than mains gas. This was of course before the current middle east conflict sent prices sharply up. Do you live a long way from a supply point? Does your heat pump software tell you how energy it consumes? And what its output is so that its COP is derived?

[Fastterry]

There’s an oil supply depot 7 miles away. The oil prices I’m using aren’t in anyway unique for people living around my location, there’s no gas supply available. The heat pump does supply energy consumption figures, so it’s possible to work out your COP. I don’t do this regularly, as my main concerns are the actual running costs per KWh.