My geothermal heating system experience

jlptheman

shane0007 wrote: »

Just read this properly. A 1C drop. What a load of nonsense! The flow rates will have to be set to absolute max. Ideal UFH delta T is 11C not 1C.

I really dont know and have no way of checking but this is what I was told by my supplier and since the rest of your information (DWH and UFH temps) is out of date then I suspect you might be out of date here too. Maybe the newer systems are configured differently. You should give Brian a buzz to discuss.

Condenser and Tommyboy08 seem to know what they are talking about so maybe one of them can clarify.

shane0007

jlptheman wrote: »

I really dont know and have no way of checking but this is what I was told by my supplier and since the rest of your information (DWH and UFH temps) is out of date then I suspect you might be out of date here too. Maybe the newer systems are configured differently. You should give Brian a buzz to discuss.

Condenser and Tommyboy08 seem to know what they are talking about so maybe one of them can clarify.

Lol, if you say so....

jlptheman

corkgsxr wrote: »

Showers are also the worst thing for transmission of legionnaires.

I know that legionnaires is a very real and dangerous threat but I'm putting my faith in technology. My DHW tank is top of the range and has been set to this temp by my supplier as per the manufacturers spec.

Fingers crossed I'll have no problems.

TPM

jlptheman wrote: »

I know that legionnaires is a very real and dangerous threat but I'm putting my faith in technology. My DHW tank is top of the range and has been set to this temp by my supplier as per the manufacturers spec.

Fingers crossed I'll have no problems.

The quality or spec of cylinder has little to do with preventing legionnaires it is a very robust bacteria, even UV cant kill it completely. The temperature range your cylinder is maintaining the water at is exactly where you dont want it.

70 to 80 °C : Disinfection range
66 °C : Legionellae die within 2 minutes
60 °C : They die within 32 minutes
55 °C : They die within 5 to 6 hours
above 50 °C : They can survive but do not multiply
35 to 46 °C : Ideal growth range
20 to 50 °C : Growth range
Below 20 °C : They can survive but are dormant

In alot of cases it is the movement of water that prevents/slows the multiplication of legionnaires and a lot of people are lucky enough to use enough hot water that it prevents the bacteria reaching dangerous levels, but this is just luck and should not be relied on

jlptheman

TPM wrote: »

The quality or spec of cylinder has little to do with preventing legionnaires it is a very robust bacteria, even UV cant kill it completely. The temperature range your cylinder is maintaining the water at is exactly where you dont want it.

70 to 80 °C : Disinfection range
66 °C : Legionellae die within 2 minutes
60 °C : They die within 32 minutes
55 °C : They die within 5 to 6 hours
above 50 °C : They can survive but do not multiply
35 to 46 °C : Ideal growth range
20 to 50 °C : Growth range
Below 20 °C : They can survive but are dormant

In alot of cases it is the movement of water that prevents/slows the multiplication of legionnaires and a lot of people are lucky enough to use enough hot water that it prevents the bacteria reaching dangerous levels, but this is just luck and should not be relied on

Some good info there cheers.

I understand what you are saying about my temp range but what I mean is that these fresh water tanks were designed to run at these temps (at least I'm lead to believe they were) so I'm hoping that this would have all been tested in a lab somewhere otherwise they would be unfit for the purpose.

I'm curious now though, I will do some investigating...

TPM

jlptheman wrote: »

Some good info there cheers.

I understand what you are saying about my temp range but what I mean is that these fresh water tanks were designed to run at these temps (at least I'm lead to believe they were) so I'm hoping that this would have all been tested in a lab somewhere otherwise they would be unfit for the purpose.

I'm curious now though, I will do some investigating...

I always seem to be over fussy about things like this. Basically if the water isnt moving and between 20-50 oC it will multiply and the longer it is in this state the more it multiplies.

If I understand your system it heats the cold fresh water almost instantaneously and this in turn minimises the volume of water maintained at the temperature and in turn reduces the risk, My concern about this type of design is that in the event bacteria do multiply to high levels the water temperature never gets high enough to kill them off and/or sterilise the pipework and components.

And as always has to be mentioned all components and systems will only do what they are designed to do if they are installed correctly and for some reason this country always seems to have issues in this area with attitudes like "sur it will be alright" "you dont really need to do all that" all too common in the past. although the attitude of doing things right is slowly working its way into the irish mentality recently

Condenser

TPM wrote: »

I always seem to be over fussy about things like this. Basically if the water isnt moving and between 20-50 oC it will multiply and the longer it is in this state the more it multiplies.

If I understand your system it heats the cold fresh water almost instantaneously and this in turn minimises the volume of water maintained at the temperature and in turn reduces the risk, My concern about this type of design is that in the event bacteria do multiply to high levels the water temperature never gets high enough to kill them off and/or sterilise the pipework and components.

And as always has to be mentioned all components and systems will only do what they are designed to do if they are installed correctly and for some reason this country always seems to have issues in this area with attitudes like "sur it will be alright" "you dont really need to do all that" all too common in the past. although the attitude of doing things right is slowly working its way into the irish mentality recently

German systems, variants of which are installed in millions of homes across europe, so the "sur it will be alright" assumption doesn't stack up. The water isn't stored so theres no issue.

shane0007

Condenser wrote: »

German systems, variants of which are installed in millions of homes across europe, so the "sur it will be alright" assumption doesn't stack up.

In Germany, they have building control. In Germany, they actually check works. In Germany, they have standards that are actually adhered to.

Condenser wrote: »

The water isn't stored so theres no issue.

So where does the water in the coil of the cylinder go to if it is not stored? This is a miniature storage cylinder, is it not?

Condenser

shane0007 wrote: »

In Germany, they have building control. In Germany, they actually check works. In Germany, they have standards that are actually adhered to.



So where does the water in the coil of the cylinder go to if it is not stored? This is a miniature storage cylinder, is it not?

Whats that got to do with anything. The system works the same regardless of what country its installed in.

You've pretty much proven yourself clueless throughout this whole thread so maybe you should go away and educate yourself besides coming on attacking technology in which you're completely out of your depth and tone done the sneering because you have a dislike of the product.

shane0007

Condenser wrote: »

Whats that got to do with anything. The system works the same regardless of what country its installed in.

You've pretty much proven yourself clueless throughout this whole thread so maybe you should go away and educate yourself besides coming on attacking technology in which you're completely out of your depth and tone done the sneering because you have a dislike of the product.

Mind now, you might take somebody's eye out throwing those toys out of that pram! Think safety first.
The reason I mentioned Germany standards is because TPM mentioned standards you replied; well in Germany.....
I never sneered, just gave my two pence worth which some will agree with & some will disagree with. I also never knocked a technology but highlight certain safety issues. If that technology is been used, IMHO the water temperature should be brought to 60C at least once per week to eliminate Legionaires. This can be done with a simple immersion & timeclock. Dealing with continuous low temperatures for DHW has proven to be fatal to both young & old & a simple best practice should be adhered.

Condenser

shane0007 wrote: »

Mind now, you might take somebody's eye out throwing those toys out of that pram! Think safety first.
The reason I mentioned Germany standards is because TPM mentioned standards you replied; well in Germany.....
I never sneered, just gave my two pence worth which some will agree with & some will disagree with. I also never knocked a technology but highlight certain safety issues. If that technology is been used, IMHO the water temperature should be brought to 60C at least once per week to eliminate Legionaires. This can be done with a simple immersion & timeclock. Dealing with continuous low temperatures for DHW has proven to be fatal to both young & old & a simple best practice should be adhered.

You've been proven wrong on umpteen occasions in this thread and when you've finished beating one dead horse you move to the next.

Regarding the sneering, that was refering to your comment where JLP said that both myself and Tommy08 knew our stuff and you replied "LOL if you say so". God forbid that anyone else might be seen as more informed than you. I've seen your form on many threads.

A Domestic fresh water system was designed to eliminate the need to heat water above 60C and yet you advocate the need to?? Maybe you should spend more time researching whats actually out there rather than spreading your perceived wisdom in an area you know nothing about. You might actually discover how a fresh water system works and that somehow ufh can operate at temps below 45C despite what your suppliers say. There's a great big world out there beyond gas boilers.

Condenser

Condenser wrote: »

German systems, variants of which are installed in millions of homes across europe, so the "sur it will be alright" assumption doesn't stack up. The water isn't stored so theres no issue.

If the unit is not used for long periods of time doesn't the water in the coil become stored?

shane0007

jlptheman wrote: »

since the rest of your information (DWH and UFH temps) is out of date then I suspect you might be out of date here too. Maybe the newer systems are configured differently.

My comment was referring to this.

shane0007

Condenser wrote: »

I've seen your form on many threads.

Please expand on this comment.

shane0007

shane0007 wrote: »

So where does the water in the coil of the cylinder go to if it is not stored? This is a miniature storage cylinder, is it not?

You also seem to completely ignore my question. As you can see, by the aid of question marks, it was a question asked of you which you still have not answered but you prefer to try & insult me.

You can also see that others also question your belief of this & also show concern but you seem to think I am attacking you on this & revert to other thread comments.

Condenser

gary71 wrote: »

If the unit is not used for long periods of time doesn't the water in the coil become stored?

How long? 2-3 weeks?? Legionaires has an incubation period of at least 10 days, after that it needs to multiply. Most systems are running in a band where the bacteria is dormant. A simple flick of the kitchen tap will run the coil clear if you're gone for weeks on end but you face the same problem with a standard system thats been sitting for weeks. Its not going to be above 60 and has spent more than a few days in the breeding zone. Legionella can live in shower heads on standard system just by feeding off the heat of water passing the branch its sitting in.

Fresh water systems have been proven safe all over europe and are becoming more popular as more and more manufacturers recognise the benefits.

Tommyboy08

shane0007 wrote: »

You also seem to completely ignore my question. As you can see, by the aid of question marks, it was a question asked of you which you still have not answered but you prefer to try & insult me.

You can also see that others also question your belief of this & also show concern but you seem to think I am attacking you on this & revert to other thread comments.

Shane you and a few others still can't seem to understand the idea of a fresh water system, the water inside the storage tank passes through the heat exchanger heating the fresh cold water instantly but the water you wash with never touches the stored water in the tank, stainless steel plates seperate them, the water in the tank could contain legionnaires, chlamydia, gonorrhoea, hepatitis, herpes and it wouldn't make a blind bit of difference as and I'll stress this again, they never come into contact!!!!!
Also don't make me laugh with the 11degree temp drop in the underfloor , never mind your 45 degree flow temps, it's systems designed like that that have ruined heat pumps in this backward country,

shane0007

Condenser wrote: »

How long? 2-3 weeks?? Legionaires has an incubation period of at least 10 days, after that it needs to multiply. Most systems are running in a band where the bacteria is dormant. A simple flick of the kitchen tap will run the coil clear if you're gone for weeks on end but you face the same problem with a standard system thats been sitting for weeks. Its not going to be above 60 and has spent more than a few days in the breeding zone. Legionella can live in shower heads on standard system just by feeding off the heat of water passing the branch its sitting in.

Fresh water systems have been proven safe all over europe and are becoming more popular as more and more manufacturers recognise the benefits.

Thank you. At last a reasonable non-attacking reply.
I have no problem with being proven wrong if I am wrong. Where I still disagree & I am entitled to disagree is the water stored within the COIL not the thermal store is also at the same temp as the water in the store. IMHO it can encourage Legionaires as it is in the realms of ideals for it. I do fully understand that this risk is low.
Traditional systems are always generally brought to 60C. After long periods, you are not going to stand under a cold shower. You will heat the cylinder first & then use the hot water.
Clean water washing through the coil of a the thermal store does not sterilise the coil so bacteria can still potentially live & infect the water around it. Again, I understand the risks are low, but if there is genuinely a risk, why not eliminate that risk?

Condenser

shane0007 wrote: »

Thank you. At last a reasonable non-attacking reply.
I have no problem with being proven wrong if I am wrong. Where I still disagree & I am entitled to disagree is the water stored within the COIL not the thermal store is also at the same temp as the water in the store. IMHO it can encourage Legionaires as it is in the realms of ideals for it. I do fully understand that this risk is low.
Traditional systems are always generally brought to 60C. After long periods, you are not going to stand under a cold shower. You will heat the cylinder first & then use the hot water.
Clean water washing through the coil of a the thermal store does not sterilise the coil so bacteria can still potentially live & infect the water around it. Again, I understand the risks are low, but if there is genuinely a risk, why not eliminate that risk?

Lets not get into the he said she said. Your questions have been fairly adversarial. You can just as easily ask me how it works. Anyway.

The risk is not small its infantesimal. You have more chance of problems with dead legs in a high temp system than you do from a FHWS. Legionella nearly always presents itself in poorly maintained cooling towers, reduntant shower heads that become used for some reason. Legionella has never been an issue in fresh water systems and they have been in use all over europe since the 80's. They are designed to eliminate the possibilty of legionella and they do it very well and allow heat pumps operate without immersions which is key.

Condenser

Condenser wrote: »

How long? 2-3 weeks?? Legionaires has an incubation period of at least 10 days, after that it needs to multiply. Most systems are running in a band where the bacteria is dormant. A simple flick of the kitchen tap will run the coil clear if you're gone for weeks on end but you face the same problem with a standard system thats been sitting for weeks. Its not going to be above 60 and has spent more than a few days in the breeding zone. Legionella can live in shower heads on standard system just by feeding off the heat of water passing the branch its sitting in.

Fresh water systems have been proven safe all over europe and are becoming more popular as more and more manufacturers recognise the benefits.

I have no experience with fresh water systems, I do come across unvented cylinders that have been left dormant for over a year and I was wondering what the considerations were in that situation, especially if the customer had a bath first.

Tommyboy08 wrote: »

Shane you and a few others still can't seem to understand the idea of a fresh water system,

I would say its more to do with communicating by text as judging by your answer you didn't get the question.



The way Legionnaires is being looked at is changing in the unvented Cylinder world, the discussions now are about which is the biggest threat scolding or legionnaires, statics are showing scolding is a bigger threat.

oikster

i have used FHWS on my last two installs and they have proved very efficient. One owner even uses the fresh hot water to fill his kettle,even more energy savings.

oikster

oikster wrote: »

i have used FHWS on my last two installs and they have proved very efficient. One owner even uses the fresh hot water to fill his kettle,even more energy savings.

What are you fitting?

oikster

gary71 wrote: »

What are you fitting?

Bespoke thermal stores with external DHW heat exchangers

jlptheman

jlptheman wrote: »

Condenser wrote: »

The inlet manifold for my UFH demands heat when the temp falls below 20degrees and stops demanding heat when it gets up to 24 or 25 degrees. My installer said that his aim was a temperature drop of 1 degree for each loop. This is why loop length and screed depth had to be precise AFAIK.

My DHW tank demands heat when it drops below 35 or 36 degrees and stops demanding heat when it reaches 44 degrees.

Lads, for the sake of accuracy then I want to make a correction to something I said earlier. I had a look at the heat pump last night and my target temps are:
DHW: 43
UFH: 28

and the trigger points seem to be:
DHW: 36
UFH: 21 (not really sure about this)

DoneDL

I have never heard of Legionnaires posing a risk from a main water supply. In order for it to breed or colonise it needs temperature and nutrition. Badly designed and maintained systems are always to blame but high temperatures are only required for stored water.
Link http://www.hse.gov.uk/legionnaires/

shane0007

DoneDL wrote: »

I have never heard of Legionnaires posing a risk from a main water supply. In order for it to breed or colonise it needs temperature and nutrition. Badly designed and maintained systems are always to blame but high temperatures are only required for stored water.
Link http://www.hse.gov.uk/legionnaires/

Nobody said it did!!!!!
If the mains water is sitting in the coil surrounded by water in the thermal store at a temperature of average 35 - 45C, this is the ideal temp for Legionaires. Bacteria does not distinguish between varying sources of water.

KoolKid

I think this has run its course.