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Thanks for the video but please no background music or if you do don't make it dynamic to your voice where it gets louder when you don't speak.

Great video again. Background music edited in a strange way, getting louder in speech breaks. (Usually use -28 - 30db throughout)

Thank you so much. Your short video summarised everything I have learned over the last 2 years since my heat pump was installed. You have clearly explained everything I have been doing wrong, and why my SCOP is only 2.2. I might even ask my wife to watch the video!

Thank you so much for this video. Just turned my weather compensation on after it being set to a flat 40 flow temp by the installers 4 years ago. I didn't dare touch it until watching this. Hopefully the on/off cycling will cut down considerably. I have a very low cost 1.30am to 6.30am tariff so actually 'charge' up my floor slab during these hours which normally means the heat pump doesn't kick back in until about 2pm when it's cold outside. It seems to work well solar and home battery usually meaning I don't have to use any high rate electric at all. Might not be the most efficient but it's definitely the cheapest and also gives me a lovely warm floor first thing in the morning :)

I really appreciate your videos man ! Tones of important knowledge!

Very good explanation which confirms what some others have been telling me. Did a test of WC and then constant 45c flow temp but only over a couple of days and no diff on energy consumed or cop but need to check over a longer period, especially as temps always diff. Please, please, please drop the music background though, it is very distracting when trying to concentrate. Thanks!

Good vid, very well explained... “3rd party control strangling the heat pump” - love that!

Wow! Thank you so much for your informative videos. I wish i had seen them a year ago. I had a heat pump installed in June, along with wall insulation, new radiators and solar panels. This was all under the ECO4 scheme, and when the company first came he said that an ASHP would definitely save me money. I live in rural Scotland and was using oiul for heating. The work took two months to complete, and afterwards the house was very comfortable. In September my electric bill rose to £139, which was bearable, but in October it rose to £283! Now I am really worried that the colder months will cost a lot more, and this indicates that the new system will not be saving me money after all. Having watched this video and checked some settings, I now know that the ASHP is not set to weather compensation and they have also given me two zones, each with an external thermostat. I have thermometers in each downstairs room, and the temperatures recorded are not good, with one room as low as 12 degrees, even though the zone thermostat is set to 17 degrees. None of the rooms are recording 17 degrees (15 degrees is the highest). The thermostats do change at different times of the day, and I now believe this could be an important issue, so I plan to change the unit to weather compensation and change the thermoststs to a static temperature all day. I hope this will make us more comfortable and reduce the costs. If not, I will be forced to look at other solutions, as I am a pensioner and cannot afford extremely large electric bills. Maybe I should have only got the solar panels and insulation. Maybe my oil bills and my electric bills will have both reduced.

Really useful - I now understand all the graphs for my Worcester CDI system boiler & Wave / EasyControl Weather Compensation 👍

Great video. Because of the info found here and other Heat Geek videos I fined tuned my system, quit zoning, no setback temps. My setup is Vaillant turbotec plus combi boiler, 12 year old, 28 KW (non condensing), 8 rads (3 - 1200x400; 4 - 1400x600; 1 -1600x600), 22 type +1 towel rail, in a single series loop, controlled by Tado thermostat with all functions active, connected and configured for ebus protocol. I`ve got a detached 70`s old brick build, 125 m2, thick walls, 450-500mm, concrete floors covered with timber board, both uninsulated; loft has 200mm mineral wool insulation, except a room; double glazing doors and windows. I heat 24/7 at 22,7 C, no setback temp, no zoning, all TRV`s are fully open. I consumed 18 mc3/day, 10 EUR/8.6 GBP (10.01.), with an average outside temp of -3C throughout the full day. Tado modulates the flow of the boiler at somewhat low temperatures 42-52C, for the example above, (the boiler does cycle) and when it`s slightly warmer (0 to 5 C outside) between 38 -46C flow; on a sunny day 36-44C flow. Considering this operation mode do you think I could switch to a condensing boiler or save it for a major renovation I am planning in 2-3 years’ time (full insulation, underfloor heating, may be a heat pump)? Thank you and i hope you extend your heat geeks network outside UK, in the future. Love your work. Greetings from Romania

Well done mate, great video👍👍

Absolutely brilliant explanation. Thank you

Great and clear video! How I wished to have such simple system :) When you add two floors, wooden flooring(limit temp to 40C max), undergrounf water heating and Nest control of one zone, do not know what degree is needed to balance the system ..

I have used an outdoor reset control on my five builds , and they work quite well , except when the wind comes up.

Fantastic video. I appreciated the idea of lower flow temperature for your ASHP equals better efficiency. But I hadn’t understood the logic behind it - balancing heat demand to heat loss whilst keeping your room at a comfortable temperature. Brilliant explanation. I will be sharing the video and testing the logic with my ASHP. Thank you

Thank you very much for providing this information. I recently moved into a new home with GSHP and had no idea how to utilise it effectively. With this knowledge, I intend to operate a more efficient system. One thing I don't understand is the degree minute setting. Currently, it is set to -60DM. Every 60 minutes, the compressor appears to cycle off and on. The compressor appears to heat up more than the projected flow temperature. Current configurations Current Value 100DM Start Compressor -60DM diff. between additional steps 100DM

Blooming great information as usual, and lovely to hear the talk about removing setback as much as possible. Would love to spend some time with you on understanding zoning. Our advice to customer is that zoning (when done correctly) allows for the comfort in each room to be controlled, i.e. your bedrooms can be controlled lower than living areas, under the number 1 rule of continual operating conditions. (mainly talking UFH but does apply to rad's as well). This can also help protect against solar gain a little in south-facing areas. But if removing demand affects the COP, we want to make sure the advice is spot on and harmonious with the rest of the industry.

Great vid. Well explained, looking forward to some colder weather (?) To try adjusting the heat curve...

Brilliant. Thank you. I'll search through your videos on the Vaillant Expanded WC now. I think that could be the next stage for us. Running at a SCOP of 3.7 for combined DHW and UF heating.

Great video as usual. I don't (yet) have a heat pump, waiting for some retrofit work to be carried out before I seriously look at that. I have a total of ten temp sensors feeding into Home Assistant -> influx, so still at data gathering stage. But have been running Viessman gas boiler at 50 flow temp for a couple of months now, have set all TRVs to max, and increased overnight temp from 15 to 17, but only since it's got warmer. I haven't tried adjusting radiators. The house is on the whole as comfortable as it was before I turned flow temp down from 60 to 50 - which is to say when we had a few cold and windy days last month(?) the living room failed to reach target temperature all day, but is pretty much ok on cold still days. I can clearly see where radiators are too big and too small (or set up incorrectly). I've checked that my Vitodens W110 is wired to allow OpenTherm communication, but I don't have weather compensation installed. I use Hive to schedule heating and I'm monitoring Hive boiler on/off data in Home Assistant as well. I also know Hive doesn't talk OpenTherm. My question is : if I get weather compensation, will it work with Hive or will Hive cancel out the weather compensation? I asked the gas engineer who serviced the boiler and he didn't seem to know although he was willing to install a weather compensation unit.

Great video, well explained!

I had homeserve fit my Worcester 4000 the fitters left the boiler in the highest settings thank god for heat geek thank you now I have cheaper bills and a warmer home 👍

Great video.

Brilliant!!! Thanks so much

Another great video. Am a huge fan. Do you have a physics degree? I do, and the way you approach the physics and the way you handle more subtle concepts (like the not turning off of the rads in less important rooms) is very familiar. If you don't have one, I'd suggest you consider it, not for vocational purposes, just because I think you would enjoy it. One one small point, and not a disagreement, but rather to add a (possible in rare circumstances) caveat: you describe (accurately) the importance of heating as many of the in-envelope rooms as possible, thus increasing emitter output and hence lowering the CH temp needed to get the total power required. And I agree with this... except for if you have a strange house! I do have a strange house and we do have a region which is poorly insulated (drafty as hell) and which we don't use in the winter. While it is 'inside' the house, we are able to block it off reasonably well, with very well sealed doors and curtains and so on. We do have enough emitters in the rest of the property to keep the central heating temp pretty low and still maintain the temp well. So anyway, I would have started with "it depends" but I think that would be misleading - I suspect your point stands in at least 90% of scenarios, so perhaps "it depends a little bit in rare occasions, maybe...". Hope that makes sense. I could go into far more detail, and I did do some very tedious calcs and really don't want to get into in-depth maths discussions (for which youtube is just the worst!) but they tipped the scales just in my circumstance, to turn off the rads in "the cold wing" of the house. It did assume I had very little leakage from the main bulk of the house into that region and I think I have achieved that. Anyway, love the channel, I use the points you make regularly with visitors who just LOVE to bemoan my heatpump when they see it, this especially includes a couple of old plumbers I know (children's friend's parents), who absolutely enjoy heat pump bashing for some reason!

Thanks for another great video

Great video and information. Struggling with the compression on the audio though

VERY informative videos, thank you for taking the time to present. I have a Daikin ASHP and I also have Fan Coil Units. You focus on Rads in your video but do you have any recommendations for settings for FCUs, am I right in thinking they will be different needs than Rads? I am specifically looking to find the LWT for achieving room temps of 21 degC in the daytime. Thank you in advance

Excellent video - our ASHP is going in next week and now I know how to go about setting the temperatures etc! Superb stuff, thanks.

Background music on auto gain is a no no, so distracting. Information is great and on point, spoilt by background music. It's really not needed unless you are in a lift.

All very important! Daikin use weather comp, if you use our room thermostat it combines this with room comp and you can even have water comp....

Brilliant clear and simple explanation. Should you set the weather compensation curve before balancing or vice versa? Thank you

I have to set my curve at about 1.1 in the winter for required temp, but that doesn't do enough when the temp out side is about 14/15 in the spring and autumn, then I need a higher curve of about 1.5-1.7 to get the rads affecting the temp enough to heat the house up to 20. Something ain't quite right with our set up but we fudge it

Awesome how you explain these matters. Question; can I use a fi Viessmann advanced controler with a Grant oil boiler?

I have an Ecodan system that works fairly well (except Mitsubishi think that it is OK for it to totally ice up for 20 minutes before a 2 minutes defrost cycle) and is reporting a SCOP of 5.0 in a very old house. My cunning plan varied the compensation curve every two weeks, plotting the amount of time the system ran against daily average outside temp. I kept dropping the curve until the system ran between 80 and 95 percent of the time. I have trialled fitting low speed computer fans under the two or three layer rads to compensate for the lack of convection at low temps and this has worked very well, with the particular rad turning off more often. These use about 5W total for a 1.5m triple layer rad, and are controlled by a cheap programmable temperature sensor, and I reckon that I will be able to drop the temp by about 2 degrees when I roll them out through the house. A commercial system reports 20% higher output with fans, but those were expensive, and the small high speed fans made the fins in the rads sing. I am also trying polycarbonate secondary glazing to reduce heat loss, and also allow lower delivery temps, with our 200 year old windows. Not that I am obsessed of course.

8 degrees outside today.Temp set to 23 degrees.Flow temp is 16 degrees.Vaillant system.

With weather comp, do you have to buy the sensor that goes outside separately or does it usually come with the boiler? Looking at a bosch 8000. Also, do they need to be hard wired to the boiler itself? Thanks for all the helpful info. 👍

What a brilliant informative video I didn't even know that ashp and some boilers had heating curves unfortunately our options are oil or electric heating as we are off the grid i think that all system condensing boilers should have heating curves

Great advice here, and presented well. We need more of this sort of stuff. The only thought I would like to add for any Ecodan owners (and others) is that I think 'Room Target' , (with no outside sensing) can be better than weather comp option, for many situations. In simple terms, this tries to achieve the desired room temp with the lowest flow temperure. I have always like weather comp, but old 'heavy' buildings behave differently to light ones, so it can be tricky to set right.

Really helpful video for a new customer in the air source heat pump market. We will definitely be looking for a Heat Geek backed installation having watched your videos but I have a technical question: in a well-insulated house (EPC - B) with a lot of glass and passive solar gain, what is the best way for the engineer to make use of weather compensation to take into account the additional passive solar gain in some, but not all, rooms ? I’m assuming, in part, the answer will be about the location of sensors that communicate with the heat pump. I’m hoping this does not mean the heat pump has to be located in the place of greatest solar gain - the front of the property is south facing (for aesthetic reasons).

I was surprised you don’t touch on Opentherm. My boiler manufacturer (Ideal, S15 Vogue) advised that Opentherm is better than Weather Compensation. I run an Evohome with UFH and boiler efficiency’s currently at 89% and increasing. I also have 2 x “air to air system” that I run spring and autumn, and obviously cooling in the summer when required

Any of your videos cover heating controls? Particularly when it comes to controlling lots of different systems together. Are there any master controllers out there to smartly select which is the best heat source to select at any one time, for example, on a time of use electricity tariff, and gas, which is cheaper/cleaner at any one time? Is there a controller that can work this stuff out and fully optimise? Maybe even learn and evolve it's algorithms as it goes along?

Very annoying background music at the start. Totally worth it though, because the information in the video is amazingly good! 👍

Does the same theory apply to my Vaillant Ecotec Plus gas boiler? It has all the necessary controls. Also, if you have multiple zones do you balance them all at once? I can set the curve for each zone! Thanks for taking the time to read and respond to all the messages on here!

Is it possible to use weather compensation with 2 zones upstairs and downstairs controlled by a hive? Most evenings I use a wood burner downstairs, would this confuse the system? I have a Daikin 3 H HT with buffer and have had quite a few issues.

Is it cheaper to run a modulating system boiler and a separate water heating cylinder/heat battery or a condensing combi boiler

Great video, for a Passivhaus with UFH, where the heat pump is going to be oversized, what would you do? Size the emitter as big as possible anyway to still run the HP at as low flow temp as possible and use the floor like one big buffer / storage heater, charging the extra thick 150mm slab once or twice a day? Would that still avoid short cycling and work with weather comp?

How does this work when the heat pump has an incorporated tank? How do you set the temperature to the tank vs room?

Very informative, great job! Going to watch it over a few times though, lots of info! 😅

For my vaillant boiler what weather compensation do you recomand?

Surely one's energy bills have the info needed to calculate a house's insulation performance. I use them to work out how much energy our house uses across the year. Mine needs improving before I can consider a heat pump as an alternative to gas boiler. What I will need is to know how to work out the best way to improve it. In my opinion, this specialist expertise is what will be most needed before 2030. The right answers for my house are not obvious.

Can I use weather compensation feature if I have buffer tank?

I have read somewhere that for every 3degrees F. That you lower the heating water there is a 1% fuel savings , does this work with a heat pump air towater.

Great video, on the VRC700 when room temp mod is set to none will the controller take into consideration the set back temp of 18 I have chosen overnight or will it continue to heat the house to 20 which the current curve does in day time

I’m currently testing my heat pump system for the correct heat curve. Bad installation (long story) and I have to set the temperature sensor to water only. The main controller is in a bad location as it’s in a Utility room with a clothes dryer so using the air sensor is not an option. Would you advise moving the controller so to avail of the air sensor also? No matter what heat curve set points I choose, the unit is spitting out heat and house is too warm!!

Do you know how Ideal combi esp1 weather compensation working?

Good information and well discussed. I did find it irritating that the camera angle and range is always changing. I know this is done to keep the brain involved but it just gave me a headache...same with music.

Great vid, thanks! 19:27 does anyone has actual sources on this? I haven't seen any information yet going against advice for frequent L cycles

I set my boiler flow for 80’c and my house can’t get passed 20.5’c. If I try 65’c I can’t get past 19’c.

For the Vaillant, to run without the thermostat switching the heating off, do you set ‘Room temp. Mod.’ To ‘None’ or ‘Temp. Mod.’ ? Thanks

After setting weather comp, you still need to use a house thermostat because the house loses much more heat in a strong freezing wind compared to a still freezing night. If you measure the kW hrs used turning the ASHP off at night, it is considerably less than running it 24 hrs per day even with set back.

Hello, Thank You so much for an in depth explanation ; I have a Midea M thermal heat pump that has option on the wired controller between desired water flow temp and desired room temp - does that have anything to do with the weather compensation - meaning if i set the desired water flow temperature the pump will always try to hit that value ? Thank You for your help !

Thank you for a really clear explanation. As someone who currently has a 10 year old condensing gas boiler, would the steps you suggest still be worth implementing, as I thought that the efficiency of the boiler drops off if it isn't on the eco setting?

Hi...Briliant Video.....just one question regarding initial preperation for setting the WC......when we put all the TRV's on Maximum should we also open up all the lockshield valves as well??

Having watched all your videos over the last few weeks I think I understand how each individual aspect works, such as weather compensation, modulation, achieving better condensing. But I'm struggling to understand how it all fits together into an ideal package. So how does having a weather compensating boiler fit with having Smart TRVs or UFH. If you have a weather compensating boiler like a Veissman 200 do you even need the Smart TRVs?

Awesome video, thank you! How long would it take to max all your internal controls, turn the heat pump on and set the compensation curve? A few hours? How long does it take a house to reach equilibrium before you can decide to tweak the curve?

Having watched the video I am a bit confused about the target temperature when re-installing the system. The instructions are to put the thermostat and the TRVs to maximum and then adjust the compensation until the target temperature is reached. Where is the system getting the target temperature from.

We are still on gas (rented) but I have done everything I can to make it efficient. I would love to hear your thoughts on my setup. We don't however use weather compensation as it's and open loop modifier and requires fettling and likely to never get it right. We have a veisman boiler which supports opentherm. Which means I can control the rad circuit temp. Wax TRV suck. Being on the radiator they do not measure (and thus control) room temperature they measure the temperature of the rad. What I have is, In each room I measure the temperature of the air on the opposite wall to where the radiator is. I also measure the temperature of the radiator. I then have underfloor heating actuators on the rad. The whole sense and control is done on a raspberry pi. It looks at the room temperature and uses a PID loop to decide what the radiator temperature needs to be. This set point is used for 2 things, as an input to a 2nd PID loop that controls the actuator on the radiator to control rad temp directly and 2nd to set the flow temperature of the boiler. The system takes all rad set points from all radiators in the house and picks the highest one for the flow temp. What this means is that one of the actuators will be on with the flow temp at exactly what that radiator needs to keep the room warm with the other rads being controls downwards. Overnight the room set points in all rooms drops, then slowly ramps up to the morning when we get up. The angle of this ramp is set fairly shallow so the boiler isn't running flat out to bring the room temps up. The colder it is outside the more the room temp drops so the boiler effectively cuts in earlier. We also have presence awareness so the system knows when we are out and drops the set points and attempts to predict when we will be back and ramps the set points up in a similar way to the day/night does. This system controls the room temp to well under 0.5c often better than 0.1c depending how much the squishy humans open doors! It's running on a raspberry pi running node-red. Boiler controlled with an Arduino mini with an opentherm adapter and graphing done using graphana. The initial setup and tuning of the PID loops took a while to get right. But now it loops after itself. Only thing I do is drop the set points at the end of the spring to stop it heating for an hour on cooler mornings

125 square meter floor plan.EPC score D what size heat pump ball park guess.How is a punter supposed to know if the installers fitted the wrong size pump when they can’t get a simple answer.If you can help great thank you, great channel like it

Can you tell me your thoughts on thermodynamics and do you think it’s better than solar thermal vacuum tubes.

Wow! Does this work for oil boilers (Grant) who offer a weather compensation add-on but not mentioned by the installer. 😡

Shouldnt be the flow temperature being adjusted to inside temperature than outside? In particular, to the room with the weakest radiator (that needs the highest temperature to get the required heating power)?

i divert the return water from my rads to a coil in a cylinder containing cold domestic water ,This preheated water is feed to the indirect tank cold taping. .Result indirect is feed with warm water and the boiler return water is at a lower temperature thus fuel savings,

I was wondering, are there optimal radiator designs for flow rate? Ie does a two column radiator flow better than a four column rad? or is there some other design altogether?

Hiya, question: my understanding is that the mitsubisi ecodan system (mine is 11kw) does auto weather ompensation when set to use the portable room stat - is this correct? so should i even bother trying to use the curve setting?

Great video again. I have a Vailliant Arotherm 7kw, UFH in new build extension (150mm insulation and screed), and oversized triple columns rads in the older part of the house (all single storey bungalow) without TRVs, all set to maximum. Existing floors insulated with 100mm mineral wool, cavities filled, and 200mm loft insulation. I am struggling to get a COP of above 2.7 looking at the controls. Currently have a single zone, with one thermostat set at 17 degrees, and 16 degrees overnight. Thanks to your videos i realized the installers set my hot water tank to 55 degrees... Ive now lowered this to 46-48 degrees (but still have the weekly legionella cycle left on). Weather compensation was set at 0.9, so have reduced slightly to 0.8. This video (correct me if i misunderstood) suggests raising the thermostat 1 degree (so in my case 18degrees), but then reducing weather compensation down so it only reaches 17 degrees? will this not just keep the heat pump on constantly, as the thermostat is calling for heat continuously?

How does an ashp such as the Vaillant arotherm plus physically change the flow temperature is it done by throttling back the flow temperature by a valve and does ashp need a buffer tank

This is unbelievably helpful and have shared with other friends with ASHPs. Thank you! Am looking for some advice on our system. All help appreciated.... We have UFH downstairs and Rads upstairs. We have two heating circuits on our Stiebel Eltron WPC10 GSHP but have been advised to run both circuits on the same heat curve because “the rads will come on with the ufh” and “the system only delivers one heating flow and return output feeding both rads & ufh so not practical to have 2 different heat curves”. I feel like we maybe losing the potential efficiency gains of having ufh running at a lower heat curve because we have rads that need a higher curve. Why have two circuits but only one output? Also, there has been mention of a ‘blending valve’ so that the ufh never goes over a particular temp - is this potentially reducing efficiency gains also? I’m in the process of ‘dialling in’ our lowest heat curve over a series of days and feel like I’m getting close, but would like to be able to drop the curve for the ufh. Thanks again for the fantastic content Heat Geek!

Weather compensation system works terrible in my air conditioning system. It completely ignores the thermal mass and isolation properties of the building. Sometimes it is comfortably chilly outside around 15 degrees, but inside it is still hot at around 25 due to the sun warming all the walls all day and the AC will just work as a fan because it thinks that the heat will radiate instead of doing what I am asking that is to remove as much heat as possible from inside the building.

Is there any chance you could consider making future videos without the background music? I'm not sure why you use it, but I personally don't think it adds anything, and I find it really distracting - especially when the volume auto-increases between your sentences. Otherwise, this is a great series. Thanks!

Just a question about weather compensation.. What happens if you were to go on holiday and want to turn off the central heating (empty house)... When you get back the house will be cold and you will switch the CH on.. With weather compensation it'll only lazily warm up rather than quickly attaining a setpoint (as the radiators won't be that hot). Is there any way around this? Other than modulating using load compensation... Or do some boilers have a weather compensation bypass for this scenario.

There's a lot of articles debunking the myth that you should turn off your heating rather than keeping it on low when you're not in the house. It sounds like for heat pumps this doesn't exactly ring true, assuming your not out of the house for days at a time. I'd assume if you are at work on a chilly winter's day you would want to be falling back to your set back temperature rather than having your heating completely off for those hours?

If it takes 8 hours to reach the comfort level e.g. 20oC from 18oC night setback - you need to increase the flow or the flow temperature?

I am currently having a strange situation. The Vaillant air to water heatpump flow temperature didn't increase to the targeted temperature( 41 C targeted vs 37 C on the flow to radiator). Seems this is causing the heatpump part of flow temperature gets very high to near 60 degrees C. The electricity consumption also increased by a factor of 3 when this happened. Any idea how to optimize it? Or it could be a problem with the system?

Am i correct in saying that everytime the system switches to hot water mode, the weather compensation program is interrupted and the supply temperature goes back up to 50C.

What if I'm away from the property for 3/4 days? What threshold does it make sense to turn the system off?

My house goes down to 6’c with heating off when it was snowing 2 weeks ago. Apart from loft insulation, what else can I do.

Can that viesmann boiler still condensate at 85 degrees when the outside temperatures are -30 although I doubt this would happen in the uk also I can't understand why all gas and oil condensing system boilers don't have this energy saving devise as it surety it wouldn't take much knowledge to replace the potentiometer with a circuit board with different resistances linked to an outside sensor

How does this work if the daytime temp is say 29 and the evening drops to 10? Can a heat pump adjust to these timescales?

Hi have you done anything on opentherm

Thank you so much for your efforts! I have one question regarding the ambiSENSE smart thermostatic radiator valve. What are the best settings for it to work properly? paired with an Ecovit 255 and VRC700? 1. Should I set Adaptive heat curve? 2. ‘Room temp. Mod. should be set to ‘None’ or ‘Temp. Mod.’ 3. It is absolutely important to have a VR71 to make work properly the VRC700? 4. I don't have any three-way valve - is it bad for the circuit? After HW is ready all radiators get suddenly ultra-hot. The circuit consists of the Ecovit with one zone and VIHR 150. What should I do to stop this effect? The Vaillant instructions are so unclear and no installer knows here hot Ambisense nor VRC700 works. Thank you in advance!

Question 1. What should I set my stat to if the house reaches below a certain temp what should I put?

Seems many houses in UK has bad insulation and non low temperature heating systems. LWT 40-50 when -5 - -10 outside OMG. My LWT is 36 when outside temperature is -25 :D And even this result can be improved.

So does advanced weather control just not work with intelligent trv and thermometers, like Tado?

Just had installed ,5 out of 7 rads could at bottom and cold returns would balancing fix this

Condensing boiler without weather compensation here. My understanding was that for maximum efficiency, my flow temp should be 57 degrees apx. Will going lower bring more efficiency?

Is there any rule of thumb about how much extra electricity is needed for the increased water flow needed for lower flow temperatures? If lowering the flow temperature of a gas boiler to a level where efficiency and comfort are ideal causes water in your radiators to flow constantly through the night (and perhaps all day as well in winters), I'm thinking that would cause some increase in electricity consumption - likely to be lower than the saving in gas consumption, but still would be good to know how to estimate this.

Dump the background music but otherwise a very good and informative vlog :-)

I wish I understood this technical info but I don't. I have had an ASHP installed and my radiators are not working well. Work done on the ECO4 scheme. Nothing was explained to me before or after installation. I have emailed the installer who is not interested and doesn't respond to my emails. System is eating up my electric and I am cold in most of the rooms in the house and a few radiators are not coming on. Can anyone suggest who I can approach to get an engineer related to this ECO4 grant scheme to check out the technical side and whether the size of pipes is correct etc? All advice welcome. Thanks