Heat Pumps

Created 30Oct2023, Last edited 01May2024

https://youtube.com/watch?v=gsvQr5apcgo
Applies to High capacity model 9 kW and higher.
06:06 volt free contacts.
If you have a number of zones or underfloor heating the Daikon units will actually connect to any third-party thermostats whether that be Salus Nest Hive, you just have to make sure that it's a volt free contact. Let's have a look at...
thermostatic control connections. This connection strip is called X2M terminal.
30 is a permanent neutral so we need to link terminal 30 and 35 which gives a signal to the heat pump to start heating mode.

2:40 bundle (with a bow)

Welcome to Ecobubl Technical Series.
Emilie explains how the Daikin High Capacity Heat Pump is wired.
If you're an Installer and require more training on Daikin Heat Pump, give us a call, we are also looking for Quality Installers to join our recommended list.
Nationwide Distribution of Heat Pumps, Mixergy Cylinders, accessories and Smart Controls.
www.ecobubl.co.uk

https://www.facebook.com/groups/684966259514987/ Heat pumps U.K. ktk member

https://www.facebook.com/groups/1432303803563678/ Heat Pumps UK and Ireland applied

https://www.facebook.com/groups/347040449610974/ Heat pumps for homes ktk member

https://www.businessjuice.co.uk/energy-guides/what-makes-up-your-electricity-price/

https://x.com/PrEuXr/status/1716014150151811078?

£7500 grant
https://www.gbnews.com/money/heat-pump-grant-installation-gas-boiler

A good heat pump COP is generally between 3.0 and 5.0, and a good SCOP is typically above 3.5.

Diagram (below) shows expected COP with 35 C° flow and 30 C° return temperatures at various outside temperatures for different sized Vaillant Arotherm models.
<https://energy-stats.uk/scop-versus-pounds-and-pence/>

TOC Is the COP on a Heat Pump Accurate?
<https://ukradiators.com/blogs/energy-saving-guides/is-the-cop-on-a-heat-pump-accurate>

Calculating SCOP
<file:///home/andymc/Downloads/App%20B%20teknical%20SCOP%20NEF%20En14825%20heatpumpsEN.pdf>

Simple example of SCOP calculation
<https://www.h2xengineering.com/blogs/heat-pump-cop-and-scop-what-they-mean-and-why-they-matter/>

====
Ratio Electric cost/Gas cost both in £/kWh

Relevant to SCOP above:
If MPs act to decouple electricity and gas £/kWh pricing so ratio electricity/gas drops heat pump running costs could look very attractive compared to gas boilers especially with low flow temperatures say at 45°C. This would boost deployment.
<https://www.nesta.org.uk/blog/the-electricity-to-gas-price-ratio-explained-how-a-green-ratio-would-make-bills-cheaper-and-greener/>

CASE 1
GAS 0.069 £/kWh COP=0.9 Annual Cost 1749 £/year FAVOURS fossil gas burning
Elec 0.2843 £/kWh COP=2 Annual Cost 3243 £/year

CASE 2
GAS*2 0.138 £/kWh COP=0.9 Annual Cost 3498 £/year
Elec/2 0.14215 £/kWh COP=2 Annual Cost 1621 £/year FAVOURS clean Heat Pumps

CASE 3
GAS equal price 0.2843 £/kWh COP=0.9 Annual Cost 7206 £/year
Elec equal price 0.2843 £/kWh COP=2 Annual Cost 3243 £/year FAVOURS clean Heat Pumps

Case 1 is present situation with part renewable Electricity approx 4 times more costly than fossil derived gas.
Case 2 is as proposed; Increase gas price and use the income to reduce electricity by same proportion - to be phased in gradually.
Case 3 equalising cost (£/kWh) of gas and electricity
Both 2nd and 3rd case FAVOURS clean Heat Pumps as present government MP's policy and greatly assists obtaining XR second demand.
https://extinctionrebellion.uk/the-truth/demands/

Private Function calcCosts(Px As Float, Ex As Float, sDesc As String) As String
'P Price per kWh( £/kWh)
'E Efficiency COP
'H Heat energy needed per Day(kWh / day)
'D Days per year heat Is Needed(days)
'C annual Cost To run( £/year)
Dim Hx, Dx, Cx As Float
Hx = 30 * 5 'kWh 'Assume per day it runs flat out for 5 hours or equivalent
Dx = 365 * (5 / 12) 'days
Cx = Px * Hx * Dx / Ex '£/year
Return sDesc & " " & Px & " £/kWh COP=" & Ex & " Annual Cost " & Round(Cx, 0) & " £/year"
End

Public Sub GasVersusHeatPump_Click()
'Print(calcCosts(Px, Ex))
Print calcCosts(0.0690, 0.9, "GAS")
Print calcCosts(0.2843, 2, "Elec")
Print calcCosts(0.0690 * 2, 0.9, "GAS*2")
Print calcCosts(0.2843 / 2, 2, "Elec/2")
'https://x.com/TheRealAndyKing/status/1329325244830642176?s=20
Print calcCosts(0.2843, 0.9, "GAS equal price")
Print calcCosts(0.2843, 2, "Elec equal price")
End

With typical October 2023 high Electric and not so high Gas prices find the Heat Pump COP making them less costly to run

Public Sub GasVersusHeatPump_Click()
Dim fCOP As Float
Print calcCosts(0.0690, 0.9, "GAS")
For fCOP = 2 To 4 Step 0.5
Print "COP = " & fCOP & " ";
Print calcCosts(0.2843, fCOP, "Elec")
Next
End

GAS 0.069 £/kWh COP=0.9 Annual Cost 1749 £/year FAVOURS
COP = 2 Elec 0.2843 £/kWh COP=2 Annual Cost 3243 £/year GAS
COP = 2.5 Elec 0.2843 £/kWh COP=2.5 Annual Cost 2594 £/year GAS
COP = 3 Elec 0.2843 £/kWh COP=3 Annual Cost 2162 £/year GAS
COP = 3.5 Elec 0.2843 £/kWh COP=3.5 Annual Cost 1853 £/year GAS
COP = 4 Elec 0.2843 £/kWh COP=4 Annual Cost 1621 £/year ELECTRIC

Output watts by input watts 17,580/4,200. That gives you 4.18 COP.

https://sprsunheatpump.com/what-is-a-good-cop-for-an-air-to-water-heat-pump.html

Air2Air heat pump

https://www.daikin.co.uk/en_gb/residential/products-and-advice/product-categories/heat-pumps/air-to-air-heat-pumps/ururu-sarara.html
one outdoor 5 indoor

https://www.daikin.co.uk/en_gb/residential/products-and-advice/product-categories/heat-pumps/air-to-air-heat-pumps/comfora.html#section-whats-included
one outdoor 5 indoor. Can go above door.
Cost of Daikin Comfora heat pump

https://www.edfenergy.com/energy-efficiency/get-an-energy-performance-certificate
EPC certificate
270mm of loft insulation as a minimum
1. After completing the form you’ll receive a call back within 48 hours
2. Your survey will then take place within 10 days
3. The actual assessment may take up to 1 hour depending on the size of your home. The assessment will involve:
taking internal and external photographs
assessing heating, ventilation and insulation
a discussion with the surveyor – they’ll be able to give you guidance on energy efficiency measures
4. You’ll receive your EPC the day after the assessment

Always make sure that your accessor is registered by checking the EPC register. Cost £35 - £120
https://www.checkatrade.com/blog/cost-guides/epc-cost/

https://www.greenmatch.co.uk/heat-pump/air-to-air-heat-pump
Gives 3 quotes
You have a valid Energy Performance Certificate (EPC) with no outstanding loft or cavity wall insulation recommendations.*
Homeowners with outstanding recommendations for loft or cavity wall insulation may still apply if the installation of these forms of insulation was completed during the voucher validity period, as indicated by a newly generated EPC at the voucher redemption stage.
On top of all these opportunities to receive a grant, you can benefit from additional financial support by paying 0% VAT on your air to air heat pump. But only until 2027
most of the modern air to air heat pumps use inverters to reduce wear and tear of the heat pump and to increase the COP.

file:///home/andymc/Downloads/Energy%20for%20Change%20-%20Consumer%20Pricing%20Guide.pdf
costs
===
For Air2Air please emphasise the higher efficiency, lower cost and use in cooling mode, increasingly an advantage with global warming.
It should be pointed out that altho Air2Air don't heat water separate efficient units are available.
https://www.modernheat.co.uk/product/100-ltr-compact-air-source-heat-pump-tesy-aqua-thermica/

If "a full bath uses up to 80 L of water whereas a five minute power shower uses about 75 L" then a 100 L tank should be adequate.
https://www.modernheat.co.uk/product/100-ltr-compact-air-source-heat-pump-tesy-aqua-thermica/
But "Heating time 7:04 h:min" needs to be factored in perhaps by shorter showers if several ppl are in household.

https://www.youtube.com/watch?v=kkNx2oSO-S4
Air Source Heat Pump 1st Winter Performance in Solid Stone Welsh Cottage
Glyn Hudson @glynhudson

https://www.youtube.com/watch?v=ibsiD5ISZqs
costs hp

Lots of other examples of real-world heat pump performance data and running costs in different types and sizes of house are available on https://heatpumpmonitor.org

The COP of a heat pump is a function of temperature lift (change from source to destination). The higher the lift the lower the COP. 30C lift at 300% COP a practical rule of thumb.
In parallel you can get twice the heat at a constant lift. In series twice the lift for the same total heat generated at the same efficiency. Higher (perhaps double) efficiency but the same total heat as a single heat pump can be achieved serially, by halving each lift.
High lift is generally a limitation of heat pumps and so a serial arrangement is a method of overcoming those limitations.
https://physics.stackexchange.com/questions/24424/efficiency-of-parallel-and-sequential-heat-pumps

A2A heatpumps can be a cost-effective option for some houses, but fitting out a whole home with indoor units in every room is challenging
https://x.com/glynhudson/status/1703200161525113280?s=20

The average UK dwelling is 90m2 and typically has radiators sized on rule of thumb at 100W/m2
https://x.com/mac_puck/status/1734687030796275794
Jim Grace @mac_puck

https://x.com/mac_puck/status/1734687030796275794?s=20
Gas boiler into HP with in/out temperatures & maths by Jim Grace

Cosy 6 is rated 6 kW for a 3 bed whereas an equiv fossil gas combi boiler would be ~30kW implying a Coefficient of Performance (CoP) of say 5.
1/
Claims for air-to-water heat pumps (A2WHP) are normally at most CoP 4 with low temperature water out say 45°C into radiators
https://www.homebuilding.co.uk/advice/air-source-heat-pumps
2/
"in mild weather COP can be about 4.0, but when the temperature drops to 0°C, the COP can also decline to 2.5"
https://www.greenmatch.co.uk/air-source-heat-pump/performance
3/
But Cosy 6 outputs high temperature water See https://x.com/PrEuXr/status/1733043709409624340?s=10
4/
One way to get hi degC out is to cascade heat pumps but this results in lower CoP as 2 compressors are needed. See
https://clade-es.com/blog/what-is-a-cascade-heat-pump-system/
5/
Maybe a more efficient Air-to-Air heat pump (A2AHP) can be cascaded into an A2WHP negating the twin compressor disadvantage. But then, oddly, UK govt grants only apply to A2WHPs.
6/

++++
heat pump kW versus gas combi boiler kW

Most top gas boilers are usually 90-94% efficient, which means that some heat will always be lost and emitted from their flue pipes.

On the other hand, heat pumps are around 300-400% efficient. Thus, you will get 3 to 4 times more heat for every kilowatt (kW) of electricity the heat pump uses.

https://www.boilerguide.co.uk/compare/types/boiler-vs-heat-pump

+++++
Most Canadian homes are timber framed and heavily insulated. They also normally have basements which makes it much easier to pipe warm air around and house the large boilers/heaters needed. My father-in-law built a house out in the country and although it was a two storey building, the lower half was effectively buried by earth works bulldozed up after construction. It looked like a bungalow built on a small hill. The whole house was very well insulated and heated by an oil & wood burner that kept everything very toasty. You could be downstairs in the winter (20 below) and just be in shirt sleeves.
My 1960’s house has a combination of solid concrete and suspended wooden floors (that have external air bricks to stop rot). My neighbours houses are now 100 and 120 years old respectively. None of us are going to be able to install an air pump without very costly & disruptive building work. This is probably true of a large percentage of existing UK properties. We tend to have mild winters here (by other peoples standards) and have built our homes accordingly. I was wearing two jumpers this winter and could only dream of wandering around in my shirt sleeves…
----
Air source heat pump active noise cancelling
<https://www.scunthorpehottubs.co.uk/product/mr-silence-ms90-9-0kw-heat-pump-ms90/>

heatpumps@ovo.com
https://octopus.energy/heat-pump-FAQ/

1:01 cavity wall insulation costs around £500 and takes 4 hrs to install
https://www.youtube.com/watch?v=tMfr1XZwEDg&t=61s

Nightmare HP
https://www.youtube.com/watch?v=1rKNT7-42J0

https://www.visitaheatpump.com/
Nesta visit HP

Replacing an oil boiler with an air-source heat pump: Why, what and how
https://www.youtube.com/watch?v=IbgeHWpqajk

Heating in UK homes produces 18% of the country's greenhouse gas emissions.
National Infrastructure Commission (NIC) estimates that air source heat pumps - the most common type for households - costs £10,000 more than a gas boiler on average.
On Thursday, the government announced there will no longer be a mandatory requirement for insulation before applying for the grant.
Izzy Woolgar director at Centre for Net Zero, an independent research unit within Octopus Energy.
Centre for Net Zero Octopus Energy
BBC News - Heat pumps still too expensive, government warned
https://www.bbc.co.uk/news/science-environment-68575271

"Octopus Heat Pump Survey Results" Has spreadsheet & joining voucher
they’re putting in a 250 litre tank, which is massive compared to my current 140 litre tank but the MCS guidelines say that for a 4 bedroom house with a bathroom and an en-suite, you fit a 250 litre tank.
crafty little automation to turn off the heating if the doors are left open for more than 5 minutes.
must comply with MCS standards, and one of those requirements is that if there is line of sight between the heat pump and a neighbouring property’s windows then planning permission must be obtained(?) https://www.speaktothegeek.co.uk/2023/06/octopus-heat-pump-survey-results-and-planning-permission/

Below has MCS steps.
We were 43 db. This means we need to get planning permission for 1 db. In fact it is worse than that. If you look at step 9 below, the number has to be rounded UP. We were actually 42.1 db which rounded to 43 db which is a fail.
Octopus has told me that a heat pump is at its most noisy when it defrosts. This will be in deep midwinter when your neighbours will have their windows closed! After seeing my Mum’s heat pump, it is not noisy at all. https://www.bazmac.me/blog/my-heat-pump-journey-with-octopus-energy

28mm pipes once lagged they become circa 50mm diameter.
divide gas usage by 2900 to get HP size.
It's taken nearly 5 months just to get a survey done. https://www.speakev.com/threads/paid-%C2%A3500-to-start-the-heat-pump-journey.183984/
GA 15Feb2024 £500 paid.
Mar Apr May Jun Jul.

27Mar2024 Octopus say they will do the survey in June and the instal in October as they are inundated with work.
https://www.speakev.com/threads/paid-%C2%A3500-to-start-the-heat-pump-journey.183984/

https://www.youtube.com/watch?v=3q7IwiZG4CM Survey hidden costs toc also £50 credit using his code

https://www.youtube.com/watch?v=XojXxLPZdp4 1st month 4:47 Aqara zigbee temperature sensors. Also £50 referral code.

Octopus watch
https://octopus.energy/blog/agile-smart-home-diy/

Eddi fitted, which diverts any surplus electricity to heating the hot water tank, only allowing export to the grid when the tank is hot.
Paid about £4K after £7,500 BUS grant.
The battery is already earning its keep though – we’ve configured the inverter to charge the battery in the cheapest time between 2am and 5am, and then to hold that charge (i.e., not discharge) until around 4pm when peak rates kick in.
What warranty is offered with the heat pump? 5 years by default, we've upgraded that to 7 years for a couple of hundred pounds. £108pa for Octopus's service plan.
Join the Solis inverter owners group on fb. Loads of tips in there.
Did they discuss flow temperatures with you whilst commissioning the system or when they visited after the install? Like another comment, mines been designed at 50c but I've heard around 35c is ideal so I plan to ask them about this.
Also, we're looking into getting the Eddi to do the legionella purge where possible, to avoid importing electricity to do that.
With the solar, it's a no-brainer.
That quote didn't change even after the survey.
Did you deploy HA on your Synology using docker?
Yep, I run HA in docker, along with a bunch of other stuff (look in my profile for my open source photo management app that I built).
If we're generating electricity from our solar array, then that frees up renewable energy capacity for somebody else who might not be able to achieve it....
I started off thinking 'old skool' but once I changed it so that the temperature is consistent through the day, it started acting more efficiently. Similarly, it keeps topping up the water tank through the day, rather than trying to heat a cold tank from 25C to 49C in an hour.
It's a mindset change, but actually gives a more pleasant environment, particularly for us where we're home most of the time
https://www.reddit.com/r/OctopusEnergy/comments/1apx2a9/i_had_a_heat_pump_fitted_by_octopus_ama/

One of the things that surprised me the most through this whole process was just how sceptical people are about heat pumps. Even smart people with good physics or engineering backgrounds would say to me "aren't you worried it won't work?". The negative PR about heat pumps not working is insanely ingrained in peoples' mindsets.
https://www.reddit.com/r/OctopusEnergy/comments/1apx2a9/i_had_a_heat_pump_fitted_by_octopus_ama/

The semi-empirical formula[*] COP = 0.342 * (t_HOT + 273) / (t_HOT - t_COLD) … t in Celsius
suggests the COP will be around 1.6
[*] my private research, based on figures from the BRE test report
http://web.archive.org/web/20181123111606/http://www.e-si.com/downloads/BRE%20Test%20Report%20Mitsi_W90.pdf
Above wayback machine
https://www.theengineer.co.uk/content/news/octopus-raises-the-temperature-with-cosy-heat-pump/

the average efficiency of the heat pumps it installs in homes is 340 per cent, meaning that 3.4 units of heat are produced for every unit of electricity used. By contrast, the average gas boiler efficiency in the UK is claimed to be just 82 per cent, making Good Energy’s heat pumps 4.1 times more efficient.
“Imagine the savings customers will make when cheap renewable power becomes abundant and electricity prices fall, or if energy bills are rebalanced so electricity is not unfairly burdened with policy costs. Gas will no longer stand a chance.”
https://www.theengineer.co.uk/content/news/new-study-claims-heat-pump-efficiency-is-4x-gas-boilers

versus Billy T...
Gas costs £0.11 per kWh and electrically costs £0.34. I would need to achieve a SCOP of 0.34/0.11 = 3 for the running costs to be the same for the same kW usage.
https://www.theengineer.co.uk/content/news/sponsored-post-heat-pump-study-reveals-the-main-barrier-to-installation

absolutely no benefit.
https://www.theengineer.co.uk/content/news/new-study-claims-heat-pump-efficiency-is-4x-gas-boilers

skillset
https://mediacdn.baxi.co.uk/-/media/websites/baxiuk/files/documentation/712148-baxi-skills-paper.pdf?v=1&d=20220705T104725Z

Gas condensing boiler
To operate in condensing mode the boiler return temperature needs to be below the dewpoint (around 54C depending on the air pressure) or
there is no condensation because the heat exchanger plate is too hot, so no
recovery of latent heat. The flow temperature will need to be adjusted to hit this target and is typically 70C or so.
The condensing is effective until the system gets to return water temperatures above 50 C, but the boiler remains far more efficient as it has more cooling surface.
https://www.theengineer.co.uk/content/news/octopus-raises-the-temperature-with-cosy-heat-pump/

Radiators

the rads changed were all changed from single emitter to doubles
https://forum.ovoenergy.com/my-smart-home-138/air-source-heat-pumps-ashp-and-radiator-replacement-how-to-work-out-the-optimum-radiator-size-for-maximum-efficiency-9594