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“Just be very careful…” (Legionella and solar)

Filed under: Latest News

Solar panels   – Solar water heating safety –   Solar heating installations safety – Solar Legionella   – Solar L8 – Best solar prices

Solar news 6 October 2009. Two years ago, in response to us providing him with hard evidence that Solartwin’s solar heating systems are safer than most, David Matthews, the Solar Trade Association’s Chief Executive sent us an email saying (these are his words):

“The legionella issue is best left alone… Just be very careful… Any mention of potentially negative perceptions that are unjustified such as… legionella that is just not happening and I will take action…”

Before looking at the context of these threats, here is some guidance which I hope will be useful.

Just be very careful if you plan to buy solar heating using a conventional twin coil solar cylinder (or “hot top” pr dedicated solar volume in space (dsvS) installations). The best solar heating installations, in terms of safety may be of other designs altogether, such as:

  • heat-to-the-base systems, also known as “hot base” installations or “dedicated solar volume in time” dsvT installations, (types 2-4 below)
  • or thermal stores (type 5 below)

These two are probably the ideal solar water heating plumbing methods. Both are used by Solartwin.

Just be very careful but please don’t panic, if you already have a twin coil solar cylinder. But first, do you actually have a twin coil cylinder? Read the label – it will usually say twin coil cylinder   – and it may also say how many litres it has as dedicated solar volume (in space).

How do I risk assess for Legionella if I already have solar thermal? Here are five options to reduce Legionella infection risk for existing twin coil cylinder solar water heating users against the levels which meet with HSE guidance. The first option is free but inconvenient. Prices of options 2-5 rise incrementally. They are suggested prices and they are only approximate!

1 – Zero cost and immediate: The simplest is just stay clear of hot and tepid water spray. Take baths, not showers. Contemplate while you are relaxing in the bath what you plan to do next: of 2-5 below. Why take a bath? This will stop you inhaling water droplets which might possibly be contaminated. If you actually disconnect all hot or warm sprays, the home may well comply with L8 which is the HSE guidance on Legionella.

2 – Cheap and cheerful (under £100 DIY, £200 otherwise) . If you can, buy and fit a long immersion heater which runs the full length of the cylinder from the top and which will reach to the bottom. You may already have one at the bottom. This is fine. Time the immersion to come on at the end of the day to heat the whole cylinder to 60C for one hour. Why? This will heat the cylinder daily to the bottom and complies with L8. Pros. Good if you can buy cheap rate electricity. You may need to change to a tariff which gave cheap leccy from say 1800H to 2000H. Cons. Not all cylinders will have a suitable top entry hole in the cylinder for the immersion heater. I am not sure if long immersion heaters are available for all solar cylinders since these tend to be taller. Heaters may not   fit – they may touch or get stuck on the heat exchangers inside. If they touch they may “spot-overheat” and fail too soon. Peak rate electricity is costly and is 2-3 times as carbon intensive per unit of energy than mains gas. So your net carbon savings from having solar may fall, possibly even to zero.

3 – Medium cost. Requiring a plumber and electrician and keeping the cylinder: (£200-£500). Have the twin coil cylinder fitted with a mains powered destratification pump which comes on: every day / holding water for one hour at 60C / in the early evening / at the same time as the water heating is turned on whether immersion or other water heater. Why? This will heat the cylinder daily to the bottom and complies with L8. Pros, medium cost. Cons, cost money to run. Uses electricity. Reduces carbon savings.

4 – Higher cost. Requires a plumber only: replacing the cylinder with a safer open vented cylinder: (£500-£1000) Replace the twin coil cylinder with another twin coil cylinder which has BOTH heat exchangers (solar and backup) at the bottom. Also time the backup heating to come on in the evening as we do. Why? Again this will heat the cylinder daily to the bottom and complies with L8. Pros: greener in that you don’t need to run an extra mains pump. Cons: arguably less green in that you are throwing stuff away. More costly than a shunt pump.

5 – Highest cost. Requires a plumber only: replacing the cylinder with a thermal store: (about £1000-£1500) Replace the twin coil cylinder with thermal store which has BOTH heat exchangers (solar and backup) at the bottom. Also time the backup heating to come on in the evening as we do. Why? Again this will heat the cylinder daily to the bottom and complies with L8. Pros: greener in that you don’t need to run an extra mains pump. Gives high pressure hot water. Gets rid of the header tank. Nice whooshy invigorating showers. Probably the legionella-safest in that the stored potable volume is the smallest and its turnover the most frequent. Cons: arguably less green in that you are again throwing stuff away. Make sure you get a large heat exchanger inside. Slightly higher store temperatures may mean you need more backup heat. Much more costly than a shunt pump. You will need to redesign your hot water system so all outlets are OK for high pressure water. For example showers need both inlets (hot and cold) to be high pessure.

Just be very careful if, as an existing or potential solar consumer, you are given safety advice on solar installations from the Solar Trade Association. A second opinion may differ – in contrast to the upbeat STA position on Legionella safety of the most common “twin coil solar cylinder” installations (also known as “hot top” installations and “dedicated solar volume in space” dsvS installations). Because a report on solar and Legionella by Dr Makin of Liverpool University Hospitals says that some conventional solar water heating installations are highly likely to be creating a risk. No wonder the solar industry stopped the report from being published, forcing us to acquire it under Freedom of Information legislation. For the record, we did not commission Dr Makin’s report, which was independently written for the Water Regulations Advisory Board. A separate report (which we ourselves commissioned from the consultants Legionella Control International) described conventional solar installations as having a “serious flaw in design“. So there is a potential problem. To discuss it is not “unjustified”.

Just be very careful if you install solar heating. Are you, as a plumber or solar installer actually insured? Let’s look at our analysis of one solar installer policy which we cannot name at present for reasons of confidentality. We are investigating the question of whether solar installers have insurance cover for dsvS installations which are specified by MCS.   I have suggested that government and its (quasi-)regulators such as MCS might want to do the same. To this end, I have been examining a particular plumbers and builders policy document which I understand is bought by thousands of plumbers. One interpretation seems to be that unsuitable installations which do not comply with HSE guidance are being promoted by DECC via illegal MCS documentation in preference to ones which do comply. Based on the interpretation that Dr Makin is correct in his assessment that conventional solar installations are “highly likely” to be creating a Legionella risk, here are six comments – on this particular insurance policy.

In Public Liability for installers:

1 – “Accidental injury” cover is excluded. A legionella risk has been foreseen as being highly likely. If or when an infection happens, it will not be unexpected, nor will it be an accidental injury. To be insurable the event should not have been foreseeable. So no cover here.

2 –   “Defective work” cover is excluded in this circumstance. So product recall / make good costs are not covered. So who will foot the bill for making good?

(And how on earth can any defective installation remain eligible for any future new state subsidy scheme?)

In Products Liability for installers:

3 – “Accidental injury” cover is excluded because as before – if or when a Legionella infection happens, and still I hope that one never does, it will not be unexpected, nor will it be an accidental injury. To be insurable the event should not have been foreseeable.   So no cover, as with Public Liability.

4 – The liability insurance excludes cover for unsuitable and defective products anyway so again there is no cover.

5 – Regarding “pollution or contamination”. Would any contamination of water by Legionella fit the acceptance criteria of being “sudden, identifiable, unintended and unexpected”? It would not be unexpected. Instead it would eventually be expected to happen. So again no cover.

6 – Regarding two key laws, the Health and Safety at Work AND the Consumer Protection Act 1987. Cover is not available where any “deliberate act or omission”… “could be reasonably have been expected to constitute a breach of applicable legislation having regard to the nature and circumstances of such act or omission”. This seems to remove cover for legal costs defending criminal proceedings.   There has been repeated deliberate omission of installing a required safety feature: a shunt pump. So no cover for legal defence costs under this Act either.

In summary, there appears to be no insurance cover at all for solar water heating installers who fit for twin coil cylinders without shunt pumps. If you are thinking about installing solar water heating and if you get a solar installation quote, ask the solar installer to speak with their insurers about cover? What did they say? If all seems OK, is it in writing?

Just be careful if as a solar water heating installer, you refer to third party excuses for continuing to install twin coil solar cylinders. They may not stack up. A supposed 50% performance drop if you don’t install solar water heating in an acknowledged legionella-risky way is claimed by four of the leading experts in the European solar industry. Our calculations show that this 50% figure is a huge exaggeration. But even when faced with these figures, the industry experts will not justfy this 50% or so figure.   I have asked all four from CEN (The European parent of the BSI) to justify this 50% but none are prepared to do so. Their high status myth is officially published.   Therefore it is unchallengable. The fact is that their exalted credentials mean that their near-holy pronouncements are so perfect mean that any challenge from unbelievers can be ignored. Who are these deities anyway?

Switzerland – Dr Jean-Marc Suter, Suter Consulting, Swiss delegate to CEN Solar Thermal Technical Committee TC312. Readers will be impressed to know that Dr Suter was polite enough to write back formally on behalf of CEN to say he would not be replying. The other three did not reply, despite reminders to do so. Thank you Jean-Marc.

Denmark – Mr Jan Erik Nielsen, SolarKey Int. God of the European Solar Thermal Industries Thermal Industries Federation and the only solar technical consultant to ESTIF named on the ESTIF website, Technical Consultant, Danish delegate to TC312.

Germany – Dr Harald Drück, ITW, German delegate to TC312., Dr Harald Drueck is the Chairman of the Solar Keymark Network.

UK – Dr Chris Laughton, FRIDPHEE (Fellow of the Royal Institute of Domestic Heating Plumbers and Environmental Engineers), UK delegate to TC312, Also consultant to BRE, author of numerous solar treatises containing outlandish myths such as “best practice is defined as conventional solar.”   Dr Laughton  is an ex-STA Chairman and a nationally acknowledged (and almost unquestionable – see below) UK solar expert witness, lobbyist, regulations writer and well, expert.

Just be very careful if, regarding Dr Laughton if you publish – particularly in the same article:

  1. His own claim of being”Frequently engaged with lobbying government, media and NGOs on solar water heating” and his being listed as the only solar thermal regulations consultant in a UK overseas trade directory.
  2. He has written, sometimes for payment, for leading NGOs such as the Energy Saving Trust and the Chartered Institute of Building Services Engineers, and the British Plumbing Education Council who produce UK’s leading state funded solar installer training materials, some of whose documents are referred to in the UK solar regulatory scene.
  3. The Lord Truscott case was unusual. It showed that combining both activities (lobbying and actual regulations writing) even if only one of these activities may actually be fee paying, is only rarely regarded as unacceptable, and is nearly always 100% legal in the technical sense.
  4. Dr Laughton is an extremely important and exceptionally busy solar expert. So busy that he can be unquestionable. Indeed he has repeatedly refused to meet us to discuss his technical encyclicals. Despite being so busy, Dr Laughton still manages to find the time to blog “inaccuracies” in order to educate the wider public. For example in one blog he pretended not to have written a document which in fact he himself had written, while pointing the public towards its link, nonetheless. This was one of the documents which defined old solar as best practice. One is forced to conclude that it was modesty, perhaps at having written so many such documents which led him not to admit authorship.
  5. With a great sense of public duty (and usually starting off by writing about his elevated status at STA, or BSI or whatever) Dr Laughton has repeatedly written inaccuracies about our solar innovation to potential major customers, and even to some regulators in UK (Trading Standards, HSE etc), inaccuracies which were of course accepted by the recipients as having no substance – but only after a lot of time was wasted.
  6. Again, keen on public duty, he freely (I must presume it was unpaid) gave impartial and independent “technical input” to the £250k Sungain solar installation project in Nottingham. In the Supply Tender he contributed “invaluable assistance in analysing suppliers answers” and he helpfully “evaluated the tender”. His involvement in and board membership of the Solar Trade Association (STA) along with the fact that both contract winners were board members demonstrates his greatness. Some STA board member companies did not win this independently evaluated contract. Given that Dr Laughton has been a contractor to one contract winner (as an independent technical writer of the market limiting BPEC solar installers manual and of its predecessors) this serves only further underline his integrity, honour and rugged capability to be totally impartial in areas where some   people (but not us) might sniff a potential conflict of interest and dare to suggest a need to stand aside, albeit hesitantly and deferentially.

Just be very careful if you write stuff like this because you will need to back up all of your claims with evidence. These facts have been merely published to demonstrate the uncontendable and all-pervasive greatness of our Dear Leader Dr Chris Laughton (long may he reign over us).

Just be very careful, whoever you are, if you dare to upset the STA. Don’t ruffle their feathers. They control much of the solar thermal market in UK. The STA will will pluck you if you don’t fly exactly where they demand. Deliberate action is now being taken by STA to damage Solar Twin Ltd for speaking out. STA have banned us from attending their annual conference so we cannot speak face to face with their members. STA are also trying to silence our voice in the UK regulatory and safety scene. Why? Because we seek to be open about the industry’s dirty laundry.

Just be very careful if you quote people out of context. People rightly don’t like being quoted out of context so, for the record, the full wording of David Matthews “just be very careful” email is below. I have added the bold for emphasis:

Barry, First of all, I am applying the arrangements to all and there are several members who are about to asked to change their websites/literature so please understand that I am not singling anyone out for special or extra treatment. I am also happy to discuss what is fair and unfair (after a suitable forum such as an MGAS meeting) but also please note that the issues here are not vague but clear cut. Side-by-side discussed the benefits of PV powered pumping and whilst I don’t want to hear about you putting down another product, I thinking it is more than fair that you promote the benefits of PV powered pumping over mains powered pumping. However, if you choose this option and other members choose to highlight some advantages of high flow mains powered systems, this is also legitimate. There is quotable info on the benefits of high flow systems. It all comes down to some common sense and using objective rather than undermining statements. The legionella issue is best left alone (for all members) as any mention of legionella and solar brings customer concerns out that are unjustified. There has never been a case of legionella anywhere in EU on a system with storage as low as 50C and any mention of legionella will reduce total sales. Ultra low flow systems losing less energy from this route, I would need to see measured evidence. Lower volume pipes equals less energy loss but bigger surface area to volume and lower flow rate equals higher energy loss. It needs to be measured not using conjecture. And it is such a minor issue compared to the big issue of energy from collector to store. Most solar systems do not have mechanical valves (if you mean 2 ports here) and sealed systems can be argued to be more reliable then open systems. I am not saying they are, just that it is open to discussion. Low voltage wires can be mistaken by an electrical installer. Anyway, I do not want to see any mention of safety issues raising any unnecessary concerns with customers No UK domestic systems are covered by the PED directive and I was looking at it carefully last year.

Barry, just be very careful. I will act if I see any evidence of mal practice on any front from any member. I don’t want to ever implement any actions against members. Just stick to measured data like side-by-side and even if you do this, sell your benefits rather than put down the opposition. By selling the benefits, we increase the total market for all. Any mention of potentially negative perceptions that are unjustified such as electrical safety or legionella that is just not happening and I will take action. I want step changes from everyone in the industry. Please try to help me realise these step changes. Thanks, David

Ps .. I am happy to look at comments in the BPEC manual (which I haven’t seen yet) and ask for revision as appropriate. I might not get it but I can ask if it is misleading. Please keep your comments on any subject such as BPEC short so I can manage the process with ease.

Just be very careful when you read the STA email. Is any part of the STA position on Legionella untenable? Is this risk really so clear cut but tiny as to best be left alone? Perhaps, instead, it is potentially too big a risk to ignore? The fact is that tepid water in Europe produces thousands of Legionella cases a year. This fact is not acknowledged above. Nor is the likelihoood that Legionella infection is under-recorded by a factor of about ten because most of it is probably lumped in with as pneumonia rather than being reduced to an individual bacterial species diagnosis. The STA, as the solar industry’s opinion formers, need to pull their head out of the sand – now!

I hope this is interesting. Nobody wants solar to cause Legionella, but we all need to look at the safety facts, at least those facts that are available – without   coercion. And if the great and the good such as Dr Laughton or David Matthews of STA come up with claims, surely they are big enough to justify and debate them without bluster and censorship (in the STA’s case) or plain refusal to supply information (in Dr Laughton’s). It’s a pity that we have had to go public with publishing material like this but the thrust of some (but not all) in the solar thermal industry is to delay, ignore and censor this debate while shooting at rather (than thanking) its messenger. You heard it first from Solartwin, the innovators!

“Just be very careful… I will take action.” Said the Solar Trade Association in 2007. And they did take action. Plenty.


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