We had our viessmann heatpump fitted start of November 2023. Very pleased with it efficiency at 460% for heating and 288% for dhw for the months of November and December. When its only cool outside say 8c to 10c it pulls about 600w per hour to deliver about 4kWh heat, so close to 600%. It close to freezing as it type this, now pulling 1.3kWh for 5.7kWh heat, so down to 400%. Flow temperature at 35c at 0c. Modern build with UFH throughout all floors. Heat Geek installer.
Thanks for the nice clear video. Probably a dumb question but in the heat pump model, why is the radiator classed as a heat 'sync' - suggesting that it's being kept 'in time' with something else - rather than a heat 'sink' that drains the heat energy from the circuit into the local environment, as used for releasing heat energy from hot electrical components?
We have a Mastertherm ground source heat pump system. We keep the room stats to max and allow the weather compensation to do the work. The system runs 24/7 and the house is 21°c throughout. It works absolutely fine and is definitely cheaper than the old oil boiler we used to run.
@@JohnBell-rf6oj hello, no we don't adjust the trv's. Occasionally overnight guests turn them down, but I think everyone's comfortable temp is different. It has taken time and tinkering of the heatcurve to get it right for our situation. We have set it as 40°C flow temp when it is -7°C outside. We heat the house as a whole rather than individual rooms and it works for us.
Excellent video - !! So we have a Calorex air source heat pump fitted into a 10 year old 4 bed detached. The house was designed with envio in mind (to get planning) - so it has all the usual suspects for good environmental performance. All the hot water is produced by the heat pump. For heating in the winter there is a small gas boiler in the garage that can boost the temperature - it kicks in automatically, but we have it switched off (just seems to go against the whole concept). Overall, quite pleased with the system. Until recently we thought it was actually quite expensive to run - but it has only been since energy costs are now for public consumption in the media we find that perhaps it is not as expensive as we were lead to believe. However, the biggest fault (our fault) is how it is used. For years we used it more like a gas boiler - on for 2 hours in morning and evening for hot water, and then on and off for heating in the winter. Now watching your videos I can see where we have gone wrong. We purchased the house new with the heat pump already installed and now I think about it we had no real instruction on how to use the system! Mark.
Hi Mark, if you also retro fit a low temp heat emitter as well your bills reduce even more. hasve attached video link ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-o7Jx3cBQNgg.html
great videos. I am in Germany and these are great videos to explain to relatives how this all works. One suggestion, can you change the graphic for how far apart the sink and source are to include different temperatures. Upon first glance people may be concerned with physical locations of the devices, which is not the intent. Oh, and can you answer the question for those in the southern US and other warmer climates: How are these more efficient than a regular A/C unit??? I know its not your typical viewers, but I think you have a great way of presenting this information.
I would be interested in what research has been done to help get as much warm air into the heat pump rather than just take normal air. By this I mean possibly siting the heat pump in a warmer area in sun. If there was an ventilation system installed in a house that had exhausts to the outside air without any heat exchanger would there be a benefit in funneling the waste air/heat from the house towards or into the main intake of the heat pump? Would it impact the SCOP at all?
I am looking at replacing my 20 year old Worcester bosch boiler. The problem for me the consumer is How would I know that a system for me was designed and setup for my property to achieve the scop values your talking about and what recourse would I have against the installer if it didn't.
I must be doing something wrong. When I compare £ savings for our Viessman 200-W gas boiler to a ASHP, I assumed: 1) A price difference of ~£6K for the purchase of a German ASHP (Vaillant) after all government incentives. 2) A SCOP of 4 for the ASHP (optimistic) and our boiler efficiency of 95% (realistic) 3) Current price cap energy tariffs of .34p and 10.5p for gas and electricity respectively and 4) A total heating demand of 15K kWh We would save £300 per annum with the heat pump. (In all likelihood, savings would be lower). It would take ~20 years to recover the added cost of the heat pump, assuming nothing went wrong. Sound right to you?
Yup, add (or already have) solar and battery storage and it can affect the equation. You should expect the difference in price of gas/electricity to change to a 2:1 ratio over the next 10 years and then to 1:1 for the final 10 years of gas.
@@peeteebee123 Not as black and white as you may believe. If the grid is green (we are only half way there), and you are able to power the ASHP outside of peak grid usage, then yes, it can be environmentally beneficial. A V200 is the greenest gas solution there is and does not rely on any of the above, nor does it have the embedded carbon costs of manufacture of the ASHP or batteries and it is immune to power transmission losses.
Hello, first efficiency have to be measured using the same units? electricity is in watts but heat is measured in joules? when something is measured in percentage, isn’t it because the units cancel out? (GCSE maths)
hi, great videos thanks you, really informative. I am shopping for an ASHP at the moment, it would be great to see reviews/comparison of the leading manufacturers, do you have any specific manufacturer and/or model you really recommend? I am seeing mixed opinions of Mitsu, Samsung, Vaillant, etc... especially for low flow temperatures, and compatibility with other tech, e.g. connecting to a Mixergy cylinder.
Thanks for another great video. It was interesting to hear that when it looking at SCOP it is biased towards the winter as that is when the heat pump is more used. Still when I look at specs for air to water heat pumps which give a specific SCOP for a specific flow temperature and out door temperature (e.g. Vaillant state their 12kw model at -5C outdoor can achieve an output of 10.8kw with a 55C flow temperature and a SCOP of 3.63). I guess I struggle to see how that applies to real life. 1: What are the assumptions made when a manufacturer states performance like that 2: How does that apply to a real life situation - Can you infer that if a system has been properly installed and never has to generate a flow temperature more than 55C then the SCOP will never be lower than 3.63? Thank you for all your videos
Would be good to break down running costs for a typical 3 bed semi. I assume that the run time and much increased cost of electricity means you don’t really get many savings from heat pumps yet
I put a brand new 18 seer heat pump in last year thinking it would save some cash when it starts getting cold, the problem is my electric cost went up 140% this year with no signs of coming down. it's more than the cost to burn oil at this point.
@@garysmith5025 thanks, much appreciated. The heat pump system we have was already installed when we purchased the house. It's taken a few years to tweak the settings, the last setting I've found is that the compressor output is based on the outside air temp. On "Auto" it provides a lot of heat very quickly, I'd hazzard a guess that it's oversized for our house so now I have the compressor output at min (runs at about 25hz and less cycling but slower recovery on DHWS). I've not seen a significant difference in consumption but less stress on the compressor must be a good thing.
We had an air exhaust heat pump from nibe that reused the heat it generated. It was crap and couldn't heat the house as it was continually sucking the heat out the house. We now have an outside heat pump that can heat the brilliantly.
@@MrAshman3000 unfortunately for NIBE that is one of the most prominent results for their products online, as with everything it has a time and a place
@1:22 Why did you even have to add a hydronic "load" leg to the system for the explanation? Radiators are mainly a European thing. I should've known to skip when I saw the backwards hat.
I have a samsung air to water heat pump , when it's cold the heat pump goes into short cycle which uses 5kw of electricity, this happens when the heating is not on ...so there for its using electricity and doing nothing!!, only when the temp outside is mild it uses less energy and when it's cold it ends up being expensive to run and the heating is not that good, can't say I'm happy with it to be honest
As a heat pump is basically compressing air shouldn't you also consider not just the temperature of the outside air but the humidity or moisture content. Also the altitude above sea level. Will a pump at sea level work differently to one on top of Everest. Flow restrictions in existing system. There must be a million things that can make each system unique and in itself different at any given time. Must be a bit like the Highway code. If you brake from 30 miles an hour it will take you X ft to stop. When in reality that stopping distance is infinite and the probability of matching that exact stopping distance even with the same car and driver in the same conditions is minimal. Too many variables. Heat pumps no doubt efficient but at what cost. And they run on electric that comes from what source. All the ducks have to be in a row to be totally efficient. Economic and environmentally friendly.
That's not how they work... it is extracting energy from the air over a heat exchanger. The compression is of the gaseous refrigerant to liquid on the other side of the heat exchanger (at yhis point putting more temp into that gas). So the variable you're searching for here is the energy in the air.
@@TheDankelsall It is the refrigerant being compressed but heat pumps are very much still affected by heat, cold, humidity and altitude. They work in the cold and heat but their efficiency is considerably affected. I used to have a heat pump. The instructions with it said efficient operating range minus 8 to 20C. Below a certain temperature in the US they recommend having a back up heat source. If you are operating at altitude the air is less dense and has less ability to carry thermal energy. Again making heat pump less efficient. The point is the condition of the environment changes how the heat pump performs and makes for infinite variables. Thus giving different readings based on those variables.
So surely if the heat pump is ~300% efficient (avg) but fuel cost is 30p/kWh and a boiler is ~100% efficient at 10p/kWh then the fuel cost will be the same? Unless we can guarantee that electricity will be significantly less than 3x the cost of gas then why would anyone take the risk today? Not to mention the disruption and costs associated with installing a heat pump. *Small tangent incoming* Heating homes with electricity and electrifying transport will prove to be massively profitable for utilities; generating free energy from wind, solar and hydro with the alternatives (oil & gas) being phased out by governments they will have no competition, meaning they can charge what they like. Great for shareholders; worrying for consumers. FYI - I'm completely on board with renewables and creating a sustainable future (and EVs are fantastic), but how do we ensure that utilities don't tear us a new one?
Gas will never be 100% efficient for heating a home unless you don't mind an explosion from the pressure build-up or killing all the occupants from oxygen deprivation. Saying a gas boiler is achieving 90% efficiency is pretty generous with the UK installs as well. One thing to note is heating with gas is affected more by price changes than a heat pump. i.e. even with the lowball 300% efficiency, electricity needs to rise by 3.3p per 1p rise in gas to have the same effect on the heating bill. There also comes a point where electricity price rises start making solar and battery storage even more worthwhile than they are today.
High efficiency is always good. But no 1 really cares about 100 plus efficiency. They care about saving money. What is your cost of 1 therm of natural gas which produces 100,000 btu. Now let's convert electricity to therms. 1 kilowatt at 100% efficiency makes 3,414 btu. 100,000 btu / 3,414 btu = 29.29 kw. In my area kw 10.38 cents. so 100,000 btu of electricity cost $3.04....ouch. This is why resistant electrical heat is so expensive. Natural gas cost about 99 cent for 100000 btu. Comparing a 95% furnace and a hsps5 10 heat pump. Heat pump cost $1.04 per 100,000 btu. Furnace cost $1.05 at 95% efficiency = 100,000 btu. At the end of the day if you live in a cold climate below 25 degree a heat pump may not be the best choice because natural gas never looses efficiency l.
I had a A/S pump given me and I have no intention of fitting it. What do I suggest then? Thermodynamic panels. A system that works but trashed by the powers that be. Broken Britain
Love your videos, awesome. I get the efficiency ratio but something not being discussed is the Carbon emissions to create the electricity at the source which In turn is used to generate power for an ASHP. End of the day, the ASHP was introduced to reduce Carbon emissions, something I simply can't get my head around when you consider most of the parts are alleged to be made in China, (Using Power coal plants etc) and kind of defeats the objective, in reducing Carbon emissions. As for wind farms (another sore point) etc, we simply don’t have enough to generate the ever-increasing need for electricity or why else would we all now be facing such high rip-off energy prices? End of the day, it's all about the Carbon footprint of an ASHP or a Gas boiler and its history of power generation maintenance and supply. A Gas boiler within a property can be turned off, electricity needs to be constantly circulated through the grid. I'm probably talking wollox, but that’s how I see it as a humble Gasman.
When you question the green credentials, they don’t reply. Start questioning the theory and the mythical 500% efficiency, then they throw personal insults. Yamaha ?
Very interesting and well explained, especially about the pressure sides and valve that controls that... how quick is the cycle or how does that work ? Or is the high pressure side always high pressure and the pressure maintains the same pressure throughout ? Very refreshing not to here any of the propaganda and conspiracy about global warming, your channel is much better without that.
Cycle is instant. The flow rate changes depending on how much power is needed.. the pressure differential is what changes.. you can't change 1 side without the other
@@HeatGeek liquid receiver is another main component part of the refrigerant cycle and enables one side to be increased or reduced without effecting the other if needed. Effectively it adds refrigerant to the circuit or removes it.
Guys this part from 2:30 - 3:00 is really misleading. Saying things like: “The heat energy doesn’t come from the electricity, it come from the air” The air outside heats a very low pressure and temp refrigerant, allowing it to ‘super heat’ and return to a gas, ready to enter the compressor. We gather some heat but it’s not yet useable, to heat anything in the house, it’s when it hits the compressor that the pressure is increased significantly and consequently the temp to a useable level. The compressor consumes a fair amount of power to do this.
The compressor consumes most of the electrical power fed into the HP. But it isn't wasted. It does work on the refrigerant, so increasing its internal energy (causing an increase in its temperature). dU=W+H if you like thermodynamics. That equation about sums up a Heat pump. The H is the heat absorbed from the environment, W is the work done by the compressor. dU is the change in internal energy of the refrigerant. You are right - the video does not correctly explain it.
The COP of a heat pump only applies to electricity used by the compressor to an equivalent amount used by an electrical resistant heater. All electric resistant heaters, including your hair dryer, have a COP of 1.0 where only a given number of BTUs will be produced per kW of electricity the device uses. Heat pumps do not produce heat, they move heat as indicated in the video. A heat pump therefore can move more heat (BTUs) per kW input (a result of the work being performed by the compressor) than heat generated by a resistance circuit. You cannot compare the COP of a heat pump directly to a natural gas, fuel oil, or propane furnace as the performance ratings are different. An accurate comparison must include the delivered heat into the home based on the cost of the fuel or electricity. Natural gas wins most of the time depending on where you live.
@@darrenr1995 Small refrigeration/heat pump circuits use hermetically sealed compressors, where the returning refrigerant gas cools the motor windings. The resistive heat from the motor is then moved to the condenser along with heat generated by the compression of the refrigerant gas. The heat generated by the compressor is likely minimal, and minimally affects the overall COP of the system.
@@mmcclen9 whether it’s mono or split , the compressor will have 4-8bar on suction side and 15-30 bar on discharge side depending on demand. This is achieved directly by work done of the compressor. Temp increase is significant across the compressor by compression of the gas. We absorb heat at the evaporator but we most certainly produce heat too. AC technology is super efficient but to say we get the heat energy just from the air and not electric is false.
My daughter lives in a housing association house, formerly a council house. Her leftie landlords decided a while back to remove the gas boilers from these houses and replace them with heat pumps. She has spent the last two winters shivering because the heat pump runs up electricity bills which she just can't afford. She is at this moment installing a wood burning stove at her own expense since the landlords refuse to accept that their heat pumps are a flop and are abdicating their legal responsibility to provide adequate heating. She is not alone. I have heard a lot about this subject and thousands of people around the country are in the same position, having heat pumps which run up eye watering electricity bills. The fact is that heat pumps are best avoided as they only seem to work properly in new houses specifically designed to work with heat pumps. If you need a new gas boiler get one. Do not be fooled into buying an expensive heat pump because you will likely regret that decision when the bills come in. I have come to the conclusion that videos like this on RU-vid are in fact sponsored by the heat pump industry and are breaking YT rules by not revealing they are sponsored.
My plan is to put an ASHP in right at the end of my upgrades. I require around 2500 KwH of electricity and 10,000 KwH of gas a year, so far My plan is as follows : Get 8 solar panels installed + battery, generating a theoretical 2000 KwH a year Reinforce my flat roof, and then get a further 8 panels with batteries. I'm already getting an inverter that can handle 16 panels. That generates a theoretical 2700 KwH a year because they can force it to face south on a flat roof. I therefore have 4700 KwH of energy to play with, leaving me with 2200 KwH (theoretically) Then I'll install an MVHR system and improve general air tightness. That should reduce my heating demands from 10,000 KwH a year to 2500-5000 KwH a year Then upsize my radiators. Then, get a heat pump. Assuming an average COP of 2.8 over the year, that'd mean I've got just over 6000 KwH worth of "heat" which is more than enough, given that I'll have had an MVHR in (ie: 2200 KwH x 2.8 = 6160 KwH) For me, the heat pump is the absolute last thing in my energy strategy. My main aim is to make my house PassivHaus. Also, fwiw the house was built in 1975 This is of course all theoretical but in theory, I could be almost self sufficient and I'd absolutely put in a heat pump right at the end, unless I was rich, and then I'd already have a ground source heat pump instead
I’d upsize the radiators first and get some weather compensation working. I don’t think you’ll get such significant improvements from MVHR, they mainly give you quality of live improvements.
Be interesting to see how the compressors cope in uk. Gas boilers arent as efficient as there are alot of factors like people arent servicing them correctly, heat exchangers inside are full of alloy oxide, so the heat is hitting dirt rather than coils. If its cleaned out at set intervals, your gonna get better transfer of heat straight away and getting better efficiency. I know you are all for heat pumps, but not everyone is as thorough as you and no one is wanting to pay big money especially in these hard times. My honest opinion is hydrogen is there to be used, it was used in town gas back in the day, but technology was nowhere near as advanced as it is now. People need to realise the carbon aspect, but considering we produce 1 percent of worlds carbon, its not the end of the world, its just a headline to try and be the first at being net zero. Plus if we made these factories, think of the jobs it could create for people in UK. It could kickstart the economic growth for all we know. These are just my views on heating aspects.
Keeping the plate (condenser) clean will be important. Soon as this get contaminated like on a combi the efficiencies will fall hugely. Compressors will have to work harder then to compensate. These can’t just be easily removed and cleaned like on a combi boiler either.
Go and watch the RU-vid info (Fully Charged) on hydrogen for heating homes. 3 main reasons against the idea stick with me. The COP would be something closer to 0.3 (not 3.0+). Nitrous Oxide production is very high because of the high temperatures involved. Finally having commissioned and worked on the hydrogen production facility myself, and seen the safety risks involved in managing hydrogen, there is no way hydrogen will getting into my home. In a carefully controlled site with all of the safety requirements, it's fine, but not a domestic situation. The technology has a long way to go before this is a viable solution.
And there was I thinking its because the electricity used to power the heat pump is turned into heat and moved inside the building along with the heat harvested
@@zlmdragon. That's true. But there are warm regions of liquid and cold regions of vapour. The phrase "When the refrigerant is warm it is in a vapour state" is not universally true. Peter Lawton 2 months ago
EVM will brag about his 5kw ASHP giving him 500% when using it to heat his home in winter between 1-5 am when the big bad frost is out there, i'm not anti heat pumps, but we know yes they work at -5, BUT how many times does the device need to cycle per 1hr at these temps. if the heat pump will be used only in the window 1-5am i would guess at a 200% max efficiency. i have a air con unit 12,000 btu as you said the same tech and yes it operates between in heat mode, at 10 outside at 1200w but at -5 you ain't going to get much heat, and in the past i did have a ASHP which operated at 13amps and delivered upto 5kw of heat, but the unit was left on 24/7 and the home was nice a toasty, leaving the efficiency of the heat pump now, i'm an electrician if heat pumps are what the say they are why the hell are most small pumps require a 16a mcb and large one's 32amp mcb.
It is like using your refrigerator to heat your house. Your claim about it being 500% efficient is saying it is a perpetual motion machine, all our problems are solved.
Heat pump principle is efficient, however nothing is free. So whilst they are efficient the down side is duration of run time. Watch a new gas boiler heat a cylinder from 20 to 60’c, takes 30/40 mins, watch a heat pump do it, takes much much longer! So end of the day you want it 60’c they both cost you. These videos are obsessed with COP.
@@darrenr1995 they also want everyone to use electricity so they can control it or shut it off. Also keep you broke. I heat with wood, I mean biofuel, natures energy battery.
If it was 'making' 5kw of heat from 1kw then yes this would be your perpetual machine and yes this is impossible! But it's not making heat - its moving heat - or pumping heat - clue is in the name! So it's using 1kw of energy to move 5kw from outside to inside.
@@TC-V8 so if you daisy chained five of these together then you could drive a steam generator that would power the units and the city you live in. Hook ten together and you could power the country.
A heat pump is not more that 100% efficient!!!!! A petrol tanker moves 30 tones of diesel from the refinery to to to petrol pumps in your town for say 0.5 tonnes of diesel. Does that make a diesel tanker 6000% efficient? If you have a machine which is more than 100% efficiency you have "over unity" and welcome to the "free energy" world. I expected better of you at heat geeks. Seems you just make false claims like all the reat which is a shame because what you promote, if you where to do do honestly, will contribute to a better, greener, future.
If you don't like the term efficiency, which is used here for convenience, then use the term coefficient of performance. The term here is simply used to determine the ratio of the heat moved against the input energy thats consumed. If you don't believe heat can be moved then please explain to me how your refrigerator works.
@@edc1569 It's not that I don't like the term efficiency, it's that it is false to claim a heat pump is more than 100% efficient. Use the correct term (COP) or just state that it is collecting x% more energy than it takes to run.
@@nickwinn7812 and yet the vast majority of normal non technical people understand it more when you say its XXX% more efficient than what they are most likely using such as a Gas boiler etc the common example of 1kwh put into a 1kwh electric radiator gives 1kwh of heat, an ASHP using 1kwh of power gives the more than just 1kwh of equivalent heat out (around 3kwh) but the COP is different at different temps and times of year
In 2014 it was announced that 3 trillion tonnes of coal had been discovered under the North sea. This coal was accessible using existing technology and would be enough to power the UK reliably for about 2000 years. We need to ditch the green energy eco madness and use this resource, only economically viable green technology should be used and only by those willing to pay the full cost themselves.
So once we’ve burnt this coal recovered by scuba miners to produce electricity, you can use it in your resistive heater and get one unit of heat or run a heat pump and got four units of heat? Or are you suggesting we all install coal fired boilers, get the wagon round with the coal every Thursday? My take is you’re pro heat pumps as they make heating from burning sub-sea recovered coal more viable - or maybe I’ve got it wrong?
The use of the word "efficiency" is annoying as it sounds like a SCAM which there are MANY so this is a bad choice of words as we WANT people to know that things can only have a less than 100% efficiency and so this is bad for PUBLIC understanding of science.