Thanks - I am very pleased you are having a new look. I ended up spending many hours becoming knowledgable on heat pumps. Sadly a lot of installers knew less than me so I got rid of those and eventually found a few that were good. Don't hesitate to ask more questions - I would be very happy to help further. Best of luck.
I do think the Vaillant is a nice looking machine. It looks well built too. There are some others that I've seen that I really think will be looking rather beat up after 7 to 10 years outside in the wet British weather.
Thanks for sharing - I move soon and have received a guesstimate from Octopus. 3 months before I can get a survey and then 5 months before I can get an install. Reflection on where the market is. British Gas confirmed they are not operating in my area. Regards Mike
I did have to work hard to find an installer with decent pricing and also a reasonable lead time. The installer I chose visited very promptly and installed the heat pump within 6 weeks. A friend had a similar lead time from them. When I was struggling to find installer I contacted Vaillant and asked them to provide some more details and that is how I eventually found the installer
Very interesting thanks for sharing. That makes me feel very pleased indeed with my setup which is similar using 8mm microbore but with hydraulic separation using a small low loss header. I got COP (heating & hot water combined) of 3.4 at -2degC average across the four days 15th to 18th Jan, and for the 6 months from Oct'23-Mar'24 combined COP was 4.2, although it has been an exceptionally mild winter.
That is great news. Make sure all the sceptics know. They are excellent COP figures. My figures are based on the open energy system. The Vaillant data gives significantly higher COP figures. Either way it is excellent.
Really interesting stuff. Thanks very much for taking the time to share your findings. I’ve recently insulated my roof and am pondering my next move into either solar/battery or a heat pump. I have a large house with 10mm microbore also, but I run my Vaillant boiler on a weather compensating control which tends to keep a flow/return of about 50 / 42 degrees if I keep the house at around 19 degrees day and night. I think therefore the heat pump will work for me without too much modification - perhaps one or two larger rads (I’ve 22 in total- it’s a big system). I’m just concerned about install cost though.. I reckon on an install bill of about £15k, reduced to 7.5k after the grant - would you agree / is this about right?
Thanks for your comment. What external temperature results in the 50C flow rate? My installation (September 2023) was in the region of £12k before the grant and for that I added 6 new type 22 radiators and moved two others. (More details on my installation are in the first video we did on my system “400% efficient microbore heat pump”) I built myself a little cost model as it is possible to find the prices of the major components such as the heat pump, controller, radiators and tank. (Midsummer Wholesale is a good place to look at prices.) 50C is well within the capability of the Vaillant heat pump but the lower you can take the flow temperature the better from a cost and efficiency point of view. The two ways of reducing the required flow temperature are house insulation and the size of your radiators. If your radiators, in the core of the house, are not type 22 I would recommend updating them. It is a very simple job to change them and will allow you to save some money.
Very informative and thanks for posting. Do you have annual maintenance contract for the heat pump? Just wondering what the indicative costs for that might be to cover potential breakdowns etc
Very interested on how you have integrated EvoHome with Vaillant SensoHome. Are you just driving smart radiators valves with the EvoHome rather than also controlling the heat pump with EvoHome?
Yes - the sensocomfort controls the heat pump and Evohome just switches the radiators on and off in the bedrooms and other peripheral areas. It works very well as the heat pump is running most of the time. I have found I need to allow longer for the bedrooms to come up to temperature if they have not been ocuupied for a bit.
@@hughrattray9354 That's great to know as most people usually ditch their EvoHome/Tado/Wiser once heat pump is installed, but sounds like its a good idea to keep it just to limit when bedrooms are heated up and to what level even though it's not controlling the heat pump directly. Think I will follow suit. Thank you.
The COP guys focus too much on that number, saying things like don't have 3rd party controls or zones or whatever. But surely the best efficiency is NOT to heat things that don't need the heat?... So bedrooms overnight, rooms with lots of solar gain, times when lots people are in, or when a big meal is cooking are all times you want room-level control. Basically I'm saying *I* decide where and when I need heat, not the pump itself or the engineers aiming for unnaturally high COP. I bet it's more efficient overall (£) to follow a good control strategy rather than chase COP.
@@TheBadoctopus Generally I agree with you but with the caveat that you need to ensure the heat pump always has enough radiators open so it can maintain the flow rate it needs. In warmer weather you can stop the heat pump from cycling by turning more radiators on until the cycling stops. Your COP will improve but the energy and cost will go up. To me the key thing is to be comfortable and use as little energy as possible. I am very happy with my system with the core area radiators always on and then separate control of other areas
@@hughrattray9354 yes, we're on the same page. I guess the challenge for us - and the industry - is now to handle this "home heat loss is below minimum heat pump modulation" situation... If the house needs 300W to maintain equilibrium, and the ASHP can't go below 600W, for example, then cycling is just a fact of life. I get that cycling lowers COP (and increasing emitter area can partly mitigate that) but honestly, does it even matter if you need less heat that the unit can provide? Clearly not. So it's a complex multidimensional problem that likely has several strategies that are good, but no guaranteed "best" because no house, weather, family and lifestyle is exactly alike.
Really good video. My house is the same 22c backbone and microbes everywhere else. 19000 kwhr gas (tank) at 19.5c but that’s a tad cool for my wife!! What temp do you run the house at for your figures. Some of us want 20-21c. Etc. Have you thought of running a cold month at 21c just to see how much more energy is used . ?? Also having free solar is actually a 15p cost due to lost export.
Thanks for the comments. I run the house at 20C most of the time with a setback in the middle of the day (when we are often out). I find that we are comfortable with a lower temperature than when we had gas because we never get cold and so don't need a big heat up. Good suggestion on the 21C I can look for a cold period to do that. I did wonder how to account for the solar value and giving it a 15p value is one of the approaches I considered. The truth is it is quite difficult to seperate the financial impact of each component of my system.
I have HR92 controllers (allowing adjustments from the room) - Having said that I have had to disable local adjustment in many rooms as the grandchildren love to fiddle with the knobs! I think I would choose the HR91 now.
That's a problem, those pesky grand kids. I'll probably get the HR91 then as will probably have grandkids, too, in the not too distant future. Thanks for your videos, very informative 👍
I have been in a dilemma about installing a heat pump since the generous RHI was running but trying to get an installer / company to even show up was impossible before the scheme finished. I have a large bungalow with micro-bore but I have no idea what the other pipe sizes are or even where they are (I suspect under the floors) so I'm not sure a heat pump is going to work or an installation be affordable. If you don't mind sharing, can you advise how much you installation cost and which company did the work? My biggest issue is the amount of investment and getting a good installation for all that money.
P..S. This probably isn't too scientific but I took your example of 8th January where you used 69kWh of heat which cost £3.20 in electric. If I used the same amount of kerosene in my existing system, based on my fuel costs (purchased last June), it would have cost me £3.66 for that same day or using 69kWh of heat. Now as I say. this is crude math, I don't know if I would use more, less or an equal amount of 69kWh of heat in this scenario but with a price difference of £0.46p for the day, if a typical heat pump installation costs £10k, if I divide £10k by £0.46, there are 21,739, divide that by 365, thats 59.5 years before I break even, I'm pretty sure my math must be flawed because that can't be right LOL
@@healeydave but that day is worst case for the heat pump. As the temperatures rise there's more heat that can be extracted more easily from the atmosphere. So heat pumps get more efficient as they get to that sweet spot where they can run at lowest power output with no cycling... Instead of a day's COP of, say, 3 (300% more heat out than energy in), in spring you'll be near 5. Then there's hot water too, and the ability to use solar and batteries to further reduce costs. Electrification is a set of strategies that add together to make each a better investment. Not to mention the reduction in pollution both locally (no kerosene burning out fumes), and globally thanks to less co2.
@@TheBadoctopus I'm all for the Eco side of things and I love the technology but it's got to be affordable and at least get close to some form of economic sense. What I mean by that is as far as I can tell there is virtually no situation where-by ripping out a working system will make economical sense. If you have a system that is actually broke, you can start factoring in the cost differential between technologies. If your current system is working (albeit not as efficient) the cost benefits are only that of the difference in running costs which will be pence per day and thats when it becomes difficult to validate (especially if your middle aged or older) unless your wealthy enough to install a system for someone else's future benefit or simply not interested in the costs and just want to do the right things Eco wise.
@@healeydave just pointing out the maths is better than you originally said... But I'm 100% with you... I've got a situation where my gas bill on my 80s bungalow is only £600-700 for a year since I've insulated, and I've still got things I can do to lower it further. So if I add a heat pump to my solar and battery setup I might save a further £100-200 a year. Not really worth it right now Vs getting an EV which will save £700-1000 per year and probably similar co2. But when gas starts getting more expensive (or electricity gets cheaper) these numbers will change pretty quickly.
There is a 3 way valve, like a gas boiler would have, this sends the hot water to either the radiators or the hot water tank as required. In the summer it is just sent to the hot water tank as no heating is required. I hope that answers your question, if not let me know.
@hughrattray9354 Thanks, tell me else do you have gravity system of your system is connected to main pipe? I do like your videos,very helpfull🫡 My system is fitted with 8mm pipes next to radiators, then 22mm ,and 28mm as yours.Do you think it would work with heat pump? Regards
Excellent. I also jave microbore and had given up on a A2W heat pump. However, after your vids, it looks like the most viable option now!
Thanks - I am very pleased you are having a new look. I ended up spending many hours becoming knowledgable on heat pumps. Sadly a lot of installers knew less than me so I got rid of those and eventually found a few that were good.
Don't hesitate to ask more questions - I would be very happy to help further.
Best of luck.
Your videos have a great format with the chat between the owner and an interested onlooker. Excellent.
Amen! We share the same experience! More comfortable, less expensive to run and not mentioning the significant carbon savings too!
Thank you for sharing. I am also planning the same with microbore pipe connected radiator. It is good to see that your system is working well.
Thanks for the comment - I am keen to dispel the myth that microbore needs to be ripped out, at huge expense, in every case. Help spread the wor!
I do think the Vaillant is a nice looking machine. It looks well built too. There are some others that I've seen that I really think will be looking rather beat up after 7 to 10 years outside in the wet British weather.
Very nice
Thanks for sharing - I move soon and have received a guesstimate from Octopus. 3 months before I can get a survey and then 5 months before I can get an install. Reflection on where the market is. British Gas confirmed they are not operating in my area. Regards Mike
I did have to work hard to find an installer with decent pricing and also a reasonable lead time.
The installer I chose visited very promptly and installed the heat pump within 6 weeks. A friend had a similar lead time from them.
When I was struggling to find installer I contacted Vaillant and asked them to provide some more details and that is how I eventually found the installer
Really helpful as we are a few weeks away from ours being fitted, we have solar and battery but may need another battery or two !
I am getting quotes for another battery - I think that would have a good return..
Very interesting thanks for sharing. That makes me feel very pleased indeed with my setup which is similar using 8mm microbore but with hydraulic separation using a small low loss header. I got COP (heating & hot water combined) of 3.4 at -2degC average across the four days 15th to 18th Jan, and for the 6 months from Oct'23-Mar'24 combined COP was 4.2, although it has been an exceptionally mild winter.
That is great news. Make sure all the sceptics know. They are excellent COP figures.
My figures are based on the open energy system. The Vaillant data gives significantly higher COP figures. Either way it is excellent.
Really interesting stuff. Thanks very much for taking the time to share your findings. I’ve recently insulated my roof and am pondering my next move into either solar/battery or a heat pump. I have a large house with 10mm microbore also, but I run my Vaillant boiler on a weather compensating control which tends to keep a flow/return of about 50 / 42 degrees if I keep the house at around 19 degrees day and night. I think therefore the heat pump will work for me without too much modification - perhaps one or two larger rads (I’ve 22 in total- it’s a big system). I’m just concerned about install cost though.. I reckon on an install bill of about £15k, reduced to 7.5k after the grant - would you agree / is this about right?
Thanks for your comment.
What external temperature results in the 50C flow rate?
My installation (September 2023) was in the region of £12k before the grant and for that I added 6 new type 22 radiators and moved two others. (More details on my installation are in the first video we did on my system “400% efficient microbore heat pump”)
I built myself a little cost model as it is possible to find the prices of the major components such as the heat pump, controller, radiators and tank. (Midsummer Wholesale is a good place to look at prices.)
50C is well within the capability of the Vaillant heat pump but the lower you can take the flow temperature the better from a cost and efficiency point of view. The two ways of reducing the required flow temperature are house insulation and the size of your radiators. If your radiators, in the core of the house, are not type 22 I would recommend updating them. It is a very simple job to change them and will allow you to save some money.
Hugh - would you consider investing in a second Powerwall to avoid using daytime electricity? (and thanks for the interesting set of videos)
Yes - I am getting quotes for a second Powerwall now - Great news tha VAT is removed from home batteries now.
Very informative and thanks for posting. Do you have annual maintenance contract for the heat pump? Just wondering what the indicative costs for that might be to cover potential breakdowns etc
Yes, I do have annual maintenance and the cost for the year just completed was £230 - it is a significant cost
Very interested on how you have integrated EvoHome with Vaillant SensoHome. Are you just driving smart radiators valves with the EvoHome rather than also controlling the heat pump with EvoHome?
Yes - the sensocomfort controls the heat pump and Evohome just switches the radiators on and off in the bedrooms and other peripheral areas. It works very well as the heat pump is running most of the time. I have found I need to allow longer for the bedrooms to come up to temperature if they have not been ocuupied for a bit.
@@hughrattray9354 That's great to know as most people usually ditch their EvoHome/Tado/Wiser once heat pump is installed, but sounds like its a good idea to keep it just to limit when bedrooms are heated up and to what level even though it's not controlling the heat pump directly. Think I will follow suit. Thank you.
The COP guys focus too much on that number, saying things like don't have 3rd party controls or zones or whatever. But surely the best efficiency is NOT to heat things that don't need the heat?... So bedrooms overnight, rooms with lots of solar gain, times when lots people are in, or when a big meal is cooking are all times you want room-level control.
Basically I'm saying *I* decide where and when I need heat, not the pump itself or the engineers aiming for unnaturally high COP. I bet it's more efficient overall (£) to follow a good control strategy rather than chase COP.
@@TheBadoctopus Generally I agree with you but with the caveat that you need to ensure the heat pump always has enough radiators open so it can maintain the flow rate it needs.
In warmer weather you can stop the heat pump from cycling by turning more radiators on until the cycling stops. Your COP will improve but the energy and cost will go up.
To me the key thing is to be comfortable and use as little energy as possible.
I am very happy with my system with the core area radiators always on and then separate control of other areas
@@hughrattray9354 yes, we're on the same page. I guess the challenge for us - and the industry - is now to handle this "home heat loss is below minimum heat pump modulation" situation...
If the house needs 300W to maintain equilibrium, and the ASHP can't go below 600W, for example, then cycling is just a fact of life. I get that cycling lowers COP (and increasing emitter area can partly mitigate that) but honestly, does it even matter if you need less heat that the unit can provide? Clearly not.
So it's a complex multidimensional problem that likely has several strategies that are good, but no guaranteed "best" because no house, weather, family and lifestyle is exactly alike.
Really good video. My house is the same 22c backbone and microbes everywhere else. 19000 kwhr gas (tank) at 19.5c but that’s a tad cool for my wife!! What temp do you run the house at for your figures. Some of us want 20-21c. Etc. Have you thought of running a cold month at 21c just to see how much more energy is used . ?? Also having free solar is actually a 15p cost due to lost export.
Thanks for the comments.
I run the house at 20C most of the time with a setback in the middle of the day (when we are often out). I find that we are comfortable with a lower temperature than when we had gas because we never get cold and so don't need a big heat up.
Good suggestion on the 21C I can look for a cold period to do that.
I did wonder how to account for the solar value and giving it a 15p value is one of the approaches I considered. The truth is it is quite difficult to seperate the financial impact of each component of my system.
Do you use the HR91 or HR92 radiator controllers? I'm assuming they do the same job, but the 92 has a digital display.
I have HR92 controllers (allowing adjustments from the room) - Having said that I have had to disable local adjustment in many rooms as the grandchildren love to fiddle with the knobs!
I think I would choose the HR91 now.
That's a problem, those pesky grand kids. I'll probably get the HR91 then as will probably have grandkids, too, in the not too distant future. Thanks for your videos, very informative 👍
I have been in a dilemma about installing a heat pump since the generous RHI was running but trying to get an installer / company to even show up was impossible before the scheme finished. I have a large bungalow with micro-bore but I have no idea what the other pipe sizes are or even where they are (I suspect under the floors) so I'm not sure a heat pump is going to work or an installation be affordable. If you don't mind sharing, can you advise how much you installation cost and which company did the work?
My biggest issue is the amount of investment and getting a good installation for all that money.
P..S. This probably isn't too scientific but I took your example of 8th January where you used 69kWh of heat which cost £3.20 in electric. If I used the same amount of kerosene in my existing system, based on my fuel costs (purchased last June), it would have cost me £3.66 for that same day or using 69kWh of heat. Now as I say. this is crude math, I don't know if I would use more, less or an equal amount of 69kWh of heat in this scenario but with a price difference of £0.46p for the day, if a typical heat pump installation costs £10k, if I divide £10k by £0.46, there are 21,739, divide that by 365, thats 59.5 years before I break even, I'm pretty sure my math must be flawed because that can't be right LOL
@@healeydave but that day is worst case for the heat pump. As the temperatures rise there's more heat that can be extracted more easily from the atmosphere. So heat pumps get more efficient as they get to that sweet spot where they can run at lowest power output with no cycling...
Instead of a day's COP of, say, 3 (300% more heat out than energy in), in spring you'll be near 5. Then there's hot water too, and the ability to use solar and batteries to further reduce costs.
Electrification is a set of strategies that add together to make each a better investment. Not to mention the reduction in pollution both locally (no kerosene burning out fumes), and globally thanks to less co2.
@@TheBadoctopus I'm all for the Eco side of things and I love the technology but it's got to be affordable and at least get close to some form of economic sense. What I mean by that is as far as I can tell there is virtually no situation where-by ripping out a working system will make economical sense. If you have a system that is actually broke, you can start factoring in the cost differential between technologies. If your current system is working (albeit not as efficient) the cost benefits are only that of the difference in running costs which will be pence per day and thats when it becomes difficult to validate (especially if your middle aged or older) unless your wealthy enough to install a system for someone else's future benefit or simply not interested in the costs and just want to do the right things Eco wise.
@@healeydave just pointing out the maths is better than you originally said... But I'm 100% with you...
I've got a situation where my gas bill on my 80s bungalow is only £600-700 for a year since I've insulated, and I've still got things I can do to lower it further. So if I add a heat pump to my solar and battery setup I might save a further £100-200 a year. Not really worth it right now Vs getting an EV which will save £700-1000 per year and probably similar co2.
But when gas starts getting more expensive (or electricity gets cheaper) these numbers will change pretty quickly.
How do you set up your heat pump in summer if there is no valve and buffer?
There is a 3 way valve, like a gas boiler would have, this sends the hot water to either the radiators or the hot water tank as required. In the summer it is just sent to the hot water tank as no heating is required.
I hope that answers your question, if not let me know.
@hughrattray9354 Thanks, tell me else do you have gravity system of your system is connected to main pipe?
I do like your videos,very helpfull🫡
My system is fitted with 8mm pipes next to radiators, then 22mm ,and 28mm as yours.Do you think it would work with heat pump?
Regards