Reducing Energy Consumption in a Large Home: A Step-by-Step Guide

#vaillant #PDHW #costofliving
In this video, I show you how I convert a highly inefficient and oversized gas boiler system into what is called a weather-compensated Domestic Hot Water Priority system and save the owners of this house an absolute fortune in their heating bills.
This job involved:
- heat loss calculations (18.50kW) and new system design
- removal of one 24kW system boiler (not needed!)
- removal of one of 300L unvented cylinders (not needed, unless there is 15 of you!)
- rewiring of the system
- supply and installation of weather compensated controls - Vaillant Senso Comfort
- integration of existing controls (12 zones) into Vaillant Senso Comfort set up
- removal of low loss header and system pump (not needed!)
- improvements to hot water performance
All those changes should save this family up to 40% on their energy use.

[@andrewmillwardwatford9410]

You have no hydraulic seperation for a system with ufh and radiators on low temperature controls. This will cause underflow in the ufh circuits when in operation. The llh needs to be refitted and a separate pump used for the radiator circuit from the distribution header. This is standard Vailant and Viessmann design. Hydraulic seperation has rules for when and when not it is required. This design you have done is subject of many of my design videos and causes regular winter call outs for me. It's very easy to rectify the issue. Ask Vilizar at Vailant to do a system schematic for you. This is as much of a hydronic no no as ccts at the ufh manifold.

[@UrbanPlumbers]

Well, we do disagree here. I’d rather have CCT on manifolds than LLH here. If I have made a mistake I want to learn from it and go back and rectify. I appreciate your experience but I would like to test it myself and go back if needed. I have seen the discussion with you and Adam re CCT and I am aware of it. I will report back

[@andrewmillwardwatford9410]

@@UrbanPlumbers it can all be proved mathematically with what you have learned from the heat geek course. I worry about credible sources giving out ideas with mistaken design principles. This leaves installers and customers vulnerable to system issues. Happy to discuss the issues with you.

[@UrbanPlumbers]

@@andrewmillwardwatford9410 sure! I would love to meet and have it all explained!

[@UrbanPlumbers]

How do I find your number mate?

[@andrewmillwardwatford9410]

@@UrbanPlumbers I message you on messenger before

[@avivscrewvalla]

What is truly amazing is that Urban Plumbers took on such a massive job and did not force the client to buy a whole bunch of new equipment to solve their issue. Instead, he deleted inefficient kit, redesigned and rewired the system and invested only time. Syzmon is the highest caliber of professional! Well done!

[@TheWebstaff]

I can't wait to see the update and note from Andrew. It was a bit of an experiment and lessons might have to be learnt. It's good to see people's working out though!

[@ogi22]

Well, i have to agree that this is amazing and a great show of high class specialist. However if they had double what they needed, i would just leave those redundant parts as a spare. Such heater is not worth a couple pennies... I have a similar sityation at my home - exchanging coal heating for gas. And i still want to leave old stove just in case, work on it a little and have an emergency heat source able to use coal, wood, chips, pellet... Hard times are coming and relying only on one source of energy is very risky.

[@edc1569]

Breath of fresh air, so tiring seeing trades just scrap perfectly serviceable equipment, incredibly wasteful.

[@chriswev]

Never met a plumber/ heating guy with half the knowledge, and ability of this guy, unreal 👍

[@microcolonel]

Finally a heating plumber who puts into his job more thought than I put into my hobbies.

[@billmarsh1971]

With these levels of competency and professionalism you should be running the entire country. Absolutely fantastic Mr Urban

[@UrbanPlumbers]

naaah - the current lot are doing great, aren't they? 😄

[@nigelsears7191]

raw talent and whats even better is you do really go above and beyond to try to make your customers systems as efficient as possible , well done Simon

[@smithleon]

Wow, what a difference. Plumbing and heating genius. As a DIY'er i'm in complete awe :)

[@silvervanmanfly]

As a plumber myself I am also in awe. A credit to the profession.

[@Umski]

I would happily endorse your ability as a real engineer unlike many of the so-called gas/boiler fitters that like to think they are! Well done on a) taking on the job, b) being tenacious and knowledgeable enough to fault find it and c) resolve it without resorting to a ‘rip it out and start from scratch’ attitude 👍

[@Umski]

@James Clerk Maxwell I have a Blue Peter badge 🤪

[@billmarsh1971]

@@Umski this is by far the most magnificent comeback I've ever seen on the internet, very well played!

[@burropoco]

Hopefully young apprentices are watching this channel and seeing a great example of what professionalism and skill looks like. It will certainly help them in their future careers.

[@tonyb3629]

It seems you have to be as much an electrician, plumber and boiler engineer - all at the same time. This is a huge, complex job that could completely fry your brain. Hat's off to you.

[@boomish69]

Love to see the original plumbers face who obviously thinks he’s the bees knees over designing such a complex system. Awesome job!

[@fredflintstone1428]

I love your channel. Your style of presenting is really natural as opposed to some on KZbin. Your knowledge is excellent and your problem solving skills really creative. Well done.

[@theamanbaby82]

Brilliant video as always. As a heating engineer myself, I can appreciate what an amazing standard you work to 👌 Keep up the good work & keep the awesome vids coming 👍

[@Flashg19811]

You are a master of your craft and I’m addicted to watching vids now about plumbing and heating…😂😂

[@UrbanPlumbers]

👍

[@Brian77766]

You are a heating genius that can simplify overcomplex systems and remove all that's not needed leaving the heating system more efficient and the customer very pleased.

[@justjacqueline2004]

I have not a clue but am fascinated by the skill of Mr Urban and his unique approach to home heating that really effects us now.

[@gheorghiuvasile266]

We can summarize that in order to save a fortune on heating costs we should call a competent and knowledgeable plumber :D very good video I quite enjoyed it, thanks for sharing!

[@davidbrotherson933]

Another great video of your work.. your depth of knowledge is incredible. I don't know how you learned all that but your customers are lucky to have such a top professional on the job.

[@delilahlynch324]

He's done the heat geek training course, best resource in the country

[@otw5974]

Your work ethic is fantastic, as others have commented. Fine tuning and efficiency - simplifying and optimising powered by thought, not excess and compensation powered by laziness and incompetence. Re the softened water thing - base exchange softened water does indeed dissolve scale deposits, you're right. However when this occurs on a large build-up, sludge can form in lower-flowing areas, or restrictions, such as strainers, filters, and aerator fittings at the end of taps, so something to look out for in a situation like this. It can also dissolve 'cleanly' over time though and eventually pass through to drain without much issue.

[@michaelhales501]

Your knowledge is incredible. You were certainly born to do this job!

[@TomNook.]

You are an artist and this heating system is a work of art

[@petehefferon8192]

It’s mental how much knowledge you keep stored in your brain. Incredible

[@xbullshet]

No idea or understanding , but it is amazing to see someone so professional and easy to understand, that he knows what he is doing and also, takes some risks to test himself. Thanks for your knowledge!

[@wilteduk007]

It's a rarity to find someone so knowledgeable.

[@willmorgan6867]

Big respect, I'm a techie not a plumber but appreciated the erasure of stuff that wasn't adding anything valuable to the system. Goes to show that there's plenty of scope to reduce energy usage and waste. Please keep making more of these, and hope you aren't kidnapped :)

[@wakayama1991]

really excellent video! Everything explained so a layperson like me can understand, delivered with humility and a sense of humour too! You sound like a true professional, not some blagging shyster (can you tell I've had a couple of those in the past?) Your customers are lucky to have you. Subscribed, and please keep the videos coming!

[@MichaelPickles]

You should open that bottle of champagne to celebrate a job well done

[@careykaeding4542]

They hired you for a reason. Tons of houses out there like this. Keep up the good work

[@UrbanPlumbers]

Thanks 👍

[@john-qq4ym]

You're amazing, managing to sort out all that wiring. I was impressed with the condition of the hot water cylinders, no limescale at all. After seeing that I went and bought an industrial water softener to fill my 4,000 litre buffer tank. I'm planning on linking an annexe and have some insulated underground water pipe, it's 32mm so I'm going to thread 16mm through to get my flow rate correct. It's only a 10 mtr. run so I think it should be fine. I'm leaving the hot water on Economy 7 as long as my contract allows. I find with a properly insulated large tank there's very little loss over the day. Some people complain about heat loss from a store but what I've found is you have to make sure there's no parasitic convection going on. Another thing I don't think people realise is that their heat store isn't fully up to temperature to start with. I can see heat stores will be very useful when smart grid pricing comes along. John.

[@johnsmith-ik8il]

I watch these videos even though I have no idea what he's talking about. What a guy.

[@stephengreen6338]

And to think I had trouble wiring a Y plan, with cylinder, and room stat, you my friend are on a higher plain, enjoy the content, well done Simone

[@Colin82ish]

Wow, so many wiring centres, my mind is blown. What a superb job you've done there, most impressive!

[@richardhalliday6469]

Chanced upon one of your videos, I was impressed by the content, presentation and professionalism - now a subscriber - excellent job my friend.

[@kenbone4535]

I love wiring heating controls, looking to be working with you soon.

[@Chris-js4yq]

Fantastic really enjoyed this as a gas engineer thank you

[@UrbanPlumbers]

Glad you enjoyed it

[@asmerom3025]

Brilliant ! Mesmerising watching a true professional at work..

[@ashplumb1]

You pal are a very clever chap. Mind is blown again

[@thomassheridan4252]

Excellent video, don't think most electricians could have worked that out.

[@spikespike9430]

Just found your channel and really impressed. You may still have a bit to learn but could be the time to ease of on the tools and make your fortune in consulting. ie How to do a proper job or correct what 'heating engineers ' have botched up and over charged on. ( only applies to some, you know who you are ) Your knowledge for your age far exceeds what an average guy knows and your videos and knowledge is truly inspirational. Well done and keep the videos coming.

[@adobo6905]

You are doing an excellent explanation with the limited time and complex installation that you have. You did not tell us if the boilers were set up to fire properly to maintain the needed space and hot water temp. You stated that energy consumption was high with not enough heating but you did not share your findings as to what caused the situation of the high energy bill. Good luck.

[@MrMattlock]

You didn't explain what you had to do to that wiring centre, but my head had exploded already by then! Why do installers make things so unnecessarily complicated? It's a lovely big house, but I've worked in 50 room hotels with simpler control systems! Well done for improving things so much for the client with minimum outlay.

[@makgou9148]

Simon strikes again. As always covers every detail as it should have been in the first place.

[@lincslegend6936]

Knowledge and skill off the scale. 👏

[@SuperMcgenius]

I like that you tried without knowing it would work. Glad it did, smart work.

[@davejohnston5158]

I have always thought commercial heating engineers have been lured by over complexity for technical one-upmanship. It appears that the clients budget usually determines the system size. In a house of this size I would expect a second boiler to be in position just to prevent inconvenient heat failure. I am amazed that all those zones work on one built-in boiler pump.

[@Lee.Willcox]

I love their choice in the heating system, I love how you have rationalised it all (BRILLIANT) and I really love their choice in paint 🤭 Farrow & Ball, they are superior producers of paint with a wonderful palette of rich colours (no I don't work for them). Such an daunting job you have taken on and you achieved it 😎

[@stephen3654]

They're not short, they can even afford Andrex.

[@Lee.Willcox]

​@@stephen3654 😄😆😅🤣I shop at LIDL and their bog roll chafes 😩 If only I could afford ALDI or ASDA bog paper, let alone Waitrose 😤😥

[@stephen3654]

@@Lee.Willcox I use my hand and rinse it in the flush

[@dglcomputers1498]

I will say the Vailant/Gloworm ebus stuff is quite handy, we had a new glowworm compact fitted at the place we are renting and no controller or even a room thermostat was fitted (the previous boiler being an ultracom with the built in programmer). Absolute pain to turn the heating on/off so ended up getting a ClimaPro2. Installed in seconds using the plug under the boiler and so much easier than having to take the front cover off to wire something internally.

[@k20aa]

I love it when a plan comes together 👍👍👍

[@schrodingerscat1863]

Guarantee the original installer looked at the house and thought, they have plenty of money, then over-specified the original system massively to make it a much bigger job than actually needed. You could run the place as a hotel on that original system, 50kW, total overkill.

[@waqasahmed939]

I've got a 29KwH boiled when realistically, I need half that. My house theoretically uses 10,000 KwH of gas a year

[@Bertie_Ahern]

Of course. Sad but true, it's only about money for most plumbers.

[@samposton9101]

Lovely work mate. What a massive difference that will make to their gas bills this year!

[@UrbanPlumbers]

There is more to it than I was able to show on the video. They had 600L of stored water and never enough hot water - 2nd circulation was constantly depleting the cylinders with 2 x boilers constantly trying to recharge them! This should make a massive improvement to energy consumption

[@samposton9101]

@@UrbanPlumbers crazy!! I suppose that’s why the secondary return should be lagged so well to stop that. At the new gas price that’s over 2.5k per year in saving!!

[@UrbanPlumbers]

@@samposton9101 yes, you can easily cost you that much with insane 600L and 50kW of boilers cycling all day

[@singlendhot8628]

@@UrbanPlumbers Reminds me of that mixing episode you did earlier in the year. Well done!

[@psi10001]

I can't wait to see the results in a year!

[@UrbanPlumbers]

I think I will go back in Jan 2023 once we have data for at least 2-3 colder months.

[@VietecHeating]

Not sure I agree with removing the LLH for such a system, however, real world testing is the best way to find out if it works, we can have all the theories we want and all the mathematical equations and all the manufacturers test rigs in test conditions, but these do not prove real working of an actual system, it’s great that you have a client willing to undergo a trial for a different approach and it will be very interesting to see how it turns out, I look forward to the follow up video with interest, it could prove a lot of theories wrong

[@UrbanPlumbers]

yes, it would be nice to keep it in, but that would require re-piping of hot water and radiator circuits so that the take-off for DHW is before the header, additional 2 pumps - one for CH rads and one for DHW plus replacement of mixing valves on 2 manifolds. It may still happen. We will know soon.

[@NickLaslett]

Great explanation of the system and the changes you made.

[@fastestmilkman3840]

Amazing work, loved how you have worked everything out first and problem-solve - wish you are closer to us in (Bath) as it is a pain to find a good plumber to install a new boiler for us at the moment!

[@andyhodchild8]

Very good video, for 30 years I fit weather compensator, the old honeywell AQ6000 was a fab weather compensator controller with optimum on and optimum off. If HMG wanted to improve efficiency they could get rid of bimetallic stats, thermistors are so much better.

[@pradhpatle]

It will succeed 👍. Have no doubt about it. I hate low loss headers when they are not needed. If in doubt I would put small buffer with buffer sensors wired to vr 71 instead.

[@mikeh6206]

I'm a Viessmann guy and have often used the boiler pump to handle full radiator loads but only when the pump is operating within its curve. The DHW 3 way valve is handled internally in the boiler so there is no question of having the wrong temp going to the tank. I can understand why the LLH is in place and if the DHW was sent to the tank bypassing the LLH, you would still have the benefit of the LLH for flow control through the secondary circuits.

[@plumbertime]

Very nice job. Sadly too many surveyors only look at what you already have and quote rather than asking what you need and would like to achieve and then quote. Sadly too many unskilled people don’t know how to work out what’s required so so just do a like for like swap. There’s plenty of big well named companies fitting systems like it’s the 90’s! And sadly customers love it because the rads get hot.

[@hogey74]

Great video thanks and salient in late 2022 in Europe. Also good seeing you discussing theory and practice in the comments.

[@andyleggatt1846]

maybe you could see if vaillant will sponsor an Arotherm addition for the property next year! ;) would have been interesting to know more about the wiring, though I appreciate the brain frying nature of boiler wiring!

[@steveeggleton876]

Yes a softener will slowly remove existing scale build up in any water using system or appliance

[@UrbanPlumbers]

I heard that before, but this is the first time I was actually able to confrim it!

[@hansv.d.p.8679]

Well..Simon..you have nailed it... bravo and keep on going...greetings from Rotterdam ..thanks for sharing .

[@gino2465]

Now that's a real nice home

[@serraios1989]

Well done for taking on the challenge!!! Could you not have salvaged the second water cylinder with an endoscope camera? Remove the heating element and stick the scope in. Less time and effort consuming. Still many thanks for the video

[@andynicolson1057]

Awesome, you're clearly the Davie504 of the plumbing world....Epic.....Slap!

[@UrbanPlumbers]

Slappers !

[@valentinmirauta7059]

Knowledgeable at its best, very good video for who is in the game and not only. Thanks

[@richardharries5551]

But of a misleading clickbait, no normal family lives like this. The owner was oversold heating cap acity and equipment. I am impressed with both your enthusiasm and knowledge as I am a retired Marine Engineer and used to large systems. Hopefully the owner gave you that bottle of champagne in appreciation.

[@UrbanPlumbers]

come on - it KZbin - it has to be a bit of a clickbait 😉 Thanks for the comment.

[@jeanjacques9980]

Fascinating video, bit mind blowing for a domestic installation, imagine a hospital!

[@Fractal227]

I need this dude to come and look at my house, if just i was not so far away xD

[@scott19087]

I always take my time to write numbers and rooms on the corresponding wires, plus I write it on a piece of paper and leave that on the boiler/heat pump. Sometimes it feels useless but seeing how much time it takes you figuring out, I’ll continue doing it lol

[@UrbanPlumbers]

I take pictures of the notes and file them under the project in Evernote. I do that for all jobs Justin case I have to trouble shoot it in the future

[@ReferenceFidelityComponents]

Decent looking boilers those. They look similar to the range topping Ideal Vogue or System boilers inside and out. Not cheap!

[@GSXRRizla]

I wish you were closer to Shropshire. I'd happily have you review and upgrade my system. If you have any recommendations for like minded installers, please share. Keep up the great work...

[@ItsFriscoBaby]

Base exchange water softeners (salt) both stop the buildup of limescale and strip the existing scale from the pipework and cylinders. It takes months or years depending on the level of existing buildup but what you had here is no surprise.

[@DJ-uk5mm]

Blimey this guy is a plumbing genius we’ll done

[@deanchapple1]

Thanks for taking the time!!

[@user-te1le7ck6b]

Mate I’m a computer science teacher and even I struggled to keep up with your Boolean logic , your simply one of a kind , I had a similar issue and still do , 38kw boiler when all I needed was 24kw at most , took years for me to be told and modulation set as best as it could , even now it’s not great but seems better. Anything else I can do bar swap the boiler ? Congrats I hope to use you when I’m back in the UK 👍👍👍

[@RayMondElec]

Hi G please explain modulation set as best as it could. . Thanks

[@user-te1le7ck6b]

@@RayMondElec engineer set the boiler to modulate down quicker so it uses less power as it doesn’t need it

[@RayMondElec]

@@user-te1le7ck6b thank you. I think that means your boiler was range rated. I may be wrong. I think the boiler in the video is a vallient 837. Mine is a vallient 937 ( in built storage tanks) . Valliant service the boiler. My total rads KW is 18. So I set it to 18kw. Valliant engineer said it is best to leave it on auto mode and switched it back🙄. He also said to leave the pump speed in Auto. Set my flow to 55C and hot water to 50C. So much conflicting info online one never really knows what to set in order to save gas and run an efficient system. 🤔

[@user-te1le7ck6b]

@@RayMondElec mine is 38kw so needed to set it down to help as best as it could

[@dontuno]

I'm always fascinated by your videos and despite what is being said by some, your knowledge way surpasses any plumber I have ever met! I'm particularly interested to note that a 24 kw boiler can provide all the heat on a 4000 square foot property given that my 1800 ish property with 11 trv'd rads and 1 hw tank struggles on a 18kw boiler even when 4 rads are isolated and the respective room doors are closed. The only suggestion I have had from a plumber is to increase the boiler to 24 kw. BTW, double glazed and copious roof insulation.

[@UrbanPlumbers]

you probably only need 10kW then. Google 'heat geek map' and hire a heat geek elite member - bigger chance to get someone who will be actually able to help you

[@dontuno]

@@UrbanPlumbers Many thanks and I will give that a go.

[@richwaight]

Brilliant work! Super interesting and well explained 🙌

[@ram64man]

The owner of the property, please post if you now have a full working 300 litre hot water tank providing all your needs or if you still experience an issue of lack enough hot water

[@AidanSkoyles]

cool; makes me appreciate simple American plumbing systems.

[@henrybartlett1986]

Well done. These are great to watch.

[@Matt.ffgmatHexPulseChain]

Brilliant job!!! 👍👍👍👍

[@SJR275]

Amazing work as always. Wish you were up in the North East so that I could get you to fix this little bungalow haha.

[@davidfellowes1628]

The overall complexity of this system and the various parts raises a question in my mind. Hotels don’t create these inter related and inter dependent systems. They work much more on a room by room basis for all variable services. Why wouldn’t something similar work better and cost less here as well, because large parts of that house aren’t used every day. Individual room or area type systems can be activated when in use and only public areas on permanently. Also the thermal envelope of this property can’t be very efficient either based on your energy consumption stats.

[@loving-plumbing]

Another well explained interesting video. Great stuff

[@Skeletoncrew46and2]

Head acratcher, pulled it off, by the looks of it. Just shows again how oversized our heating system are. Perfect example of over engineering. Nice work!

[@UrbanPlumbers]

my head still hurts from tracing all those wires!

[@Skeletoncrew46and2]

@@UrbanPlumbers oh man that's a massive detective job. Well done.

[@SisterAbdullahX]

Awesome job as ever. Got to be honest, I wouldn’t have tackled that job, far too much thinking for my brain to deal with! Have you done any formal electrical training or did you just learn as you went along?

[@UrbanPlumbers]

I only had basic electrical training

[@krissybufton]

I absolutely love your videos man!! I keep watching with a view of trying to work out why my heating system is so inefficient ! I live down near Portsmouth, would you travel this far to try and help me make my system work better ? I have a highly disabled daughter who requires constant temperature consistency and I struggle to keep everything working nicely for her! I have a Worcester Bosch life system boiler with an unvented 250l cylinder and underfloor heating in areas throughout the downstairs with a scope of extending this underfloor heating when works are done. I’m constantly wrestling with it to try and keep my bills down!!

[@UrbanPlumbers]

Google ‘heat geek map’ for a better chance of finding an engineer who understands efficient heating systems

[@krissybufton]

@@UrbanPlumbers oooh I’ll look into it ! Thanks

[@MrSunnyBhoy]

You should be teaching at a university mate. You are that good.

[@chrispychan4547]

Awesome plumbing man. Would love to understand the electronics side to your level one day.

[@nedloh17]

A heating engineer Wizard !!

[@johndevlin980]

That’s amazing mate, good work 👍

[@deanchapple1]

Well done! Phenomenal knowledge and courage to take on such a can of worms!! Elite engineer!! 💪🏼😊👍🏼 Although I think Andrew Millward may have a point and his words may come to haunt you?….. 👍🏼

[@euroasiabtlimited3208]

Great work . Thanks for sharing all that valuable information .

[@hansgroenewegen6910]

You.are.a.good.plummer! Very good video. Thank you!

[@chrisillingworth7967]

Fantastic and informative video. Ain’t the main reason for a llh where there is multiple pumps with ufh? To stop them influencing flow rates outside of the international pump flow? Hydronic separation, Not just for when you have two boilers together.

[@UrbanPlumbers]

Yes that is correct. However even with LLH in you still have a system pump influencing 2 manifolds pumps. I had a 2 hour discussion on how to address this with Andrew Millward today. I would just use CCT on manifolds as per Adam from HeatvGeek but Andrew is set against it and says it is as bad as no separation. I think I may put LLH back but without the system pump and just add 1 pump for rad circuit. I think this was a consensus we reached with Andrew. There is going to be a follow up on this soon. Another solution would be to use one boiler for rads and cylinders and separate the system with 2nd boiler just doing UFH on low temp. Unfortunately all those option add a cost to the install

[@LocostR1]

@@UrbanPlumbers Andrew's solution for my Vaillant install would probably work well, using electronic mixing valves or mixing groups controlled by the VR71 to supply WC controlled heat curves to each emitter type kzbin.info/www/bejne/bYmYhYWVmpV9gK8

[@johnmit]

It's a fantastic example that complexity does not automatically give you better efficiency, control or cost savings - and it can do the very opposite. I wonder how much all those extra thermostats (and the perceived extra control) actually saves them when compared to a simpler well balanced system. My guess is not as much as they think. And also why use underfloor heating manifolds with cheaper actuators when you can make you own out of hundreds of tees and individual zone valves... The labour time alone on all that soldering....

[@jackman19911]

Just taking that cylinder out is going to save a lot of money. Issue I find in installations with llh is how the circuits are run, dhw should be before the header/heat ex on priority so then all heating circuits can freely modulate

[@UrbanPlumbers]

Exactly! Thank you.

[@Thedar561]

Is running a 2000 LTR buffer tank with an UFH system a good idea in relation to efficiency ??

[@stigkrakpants3052]

Does this video and his amazing work fill me with confidence that there are good tradesmen out there - who are honest and demand the best for client; or does this video worry the hell out of me that i will only find a poor or below par tradesman, who will rip me off and leave me with a crappy short lived system...?

[@offgridwanabe]

Brilliant the outdoor sensor is the weak point imho at least if your weather changes fast.