PDA

View Full Version : Vrv Safety Concerns



ralph feria
09-10-2004, 12:44 PM
The Usa Is Just Beginning To See Vrv Sales And Installation. A Concern Was Raised About Vrv Systems Using A Rather Large Amount Of Refrigerant That Could Be Potentially Discharged Into A Space During A Coil Failure And Thereby Displacing The Oxygen In That Space . Our Application Is For A Nursing Home. We Are Concerned That We Could Be Creating A Life Threatening Situation For The Invalid Patients. Does Anyone Have Any Experince In Similar Applications?

chemi-cool
09-10-2004, 12:53 PM
Hi Ralph.

If it worries you and there is a point in what you say, then the why not use a water chiller with fan coils for that area.

The worse scenario is water leak.

Chemi :)

ralph feria
09-10-2004, 01:08 PM
Thanks For The Reply. Do You Know Of Any Instances That A Rupture Or Leak Has Caused A Problem? I Have Been Told That Since Europe Has The Longest Exposure To Vrv Systems It Is The Place To Ask The Questions.

Latte
09-10-2004, 05:11 PM
Hi Ralph,

While in therory it is possible to have an oxygen depletion due to a gas leak in practice the risk is so small that no one really wories about it.
take into consideration,
1) the system should be strenght/pressure tested so if the system holds this pressure then chances of a leak are small.
2) nursing homes are not air tight therefore if there is a leak there will still be air moving about.
3) If there is that big a leak then providing the safty systems are working ok it should still cut out.
4) If you are that worried about it fit gas alarm sensors although personally i dont see the point.

Why are you fitting a vrv system, how many indoor units, are you fitting in all rooms inc bedrooms or just in the larger meeting rooms.

VRV technology is all very good but unless you are fitting lots of indoor units i would also consider splits.


regards

Fatbot

chillyhamster
09-10-2004, 09:38 PM
We in europe are lucky ?, to have impending legislation, namely f-gas and H&S refrigerant in enclosed spaces which will mean the installation of refrigerant detction systems in any areas which can be classified as an enclosed space with non trained occupation or access. HC air conditioning allready has limits to the potential HC / air ratio's which limits their application.

ralph feria
09-10-2004, 10:56 PM
Thanks For The Reply. Do You Have "murphys Law" In Gb? It Says "anything That Can Go Wrong Will". Remember They Told The Neighboring Residents At Chernobyl And Three Mile Island That There Were Multiple Redundant Systems To Keep Them Safe. That "they Had Nothing To Worry About" On Another Reply To This Thread It Was Written That Europe Has Regulations That Will Require Gas "sensing". Is This In Respose To A Fatality? Government Is Rarely Proactive.

ralph feria
09-10-2004, 11:02 PM
DEAR CHILLY HAMSTER,
I AM NOT GETTING A WARM FUZZY FEELING AS I READ THE REPLYS ON VRV TECHNOLOGY. IN FACT IT IS RAISING A LOT OF CONCERNS. DO YOU KNOW OF ANY FATALITIES CAUSED BY VRV SYSTEMS? CAN YOU POINT ME TO COPIES OF "F GAS" AND "H&S"?

THANKS FOR HELPING!!


We in europe are lucky ?, to have impending legislation, namely f-gas and H&S refrigerant in enclosed spaces which will mean the installation of refrigerant detction systems in any areas which can be classified as an enclosed space with non trained occupation or access. HC air conditioning allready has limits to the potential HC / air ratio's which limits their application.

Latte
09-10-2004, 11:47 PM
Hi Guys,
The problems at TMI & Chernobyl were caused by a sequence of events, equipment malfunction, design problems and operator errors. At TMI for instance when an electrical problem with cooling pumps failed causing the reactor to overheat and a blow off valve that should have reset didn't.

Chernobyl was caused by untrained engineers tring to restart a reactor after going below its minimum power setting.

Either way, we in our industry are not facing the kind of casatrophic conciquenses of a system failure.
TMI OFFICIALLY :confused: no one suffered from long term problems to radioactivity unfortunatly Chernobyl thousands of people wern't so lucky.

I Think since these problems, companies are far more aware of litigation and systems these days are tested almost to distruction before being released to the market. remember there if far more OPEN regulation in our industry and more is known about the workings of a VRV sytem then will ever be in the nuclear industry.

Regards

Fatboy

chillyhamster
09-10-2004, 11:48 PM
Not goverment. EU.

Coolie
18-10-2004, 10:21 PM
I agree with all of the replies!
Although I've only been in the industry for 5 years now, First installing and now i've made the move to service, but I've never seen nor heard of such a problem as you mention.
If you are worried, contact Daikin themselves for a safety report!
As far as I'm aware such info should be freely available. I know that they do leak detectors and many safety paraphernalia to go along with it all. After all they have to sell a product that is safe enough for everybody otherwise they would not be in business.

As long is the install is of high quality there should not be a problem!!!

ralph feria
22-10-2004, 02:53 PM
Dear All,
On This Side Of The Atlantic We Live, For Better Or Worse, In A Highly Litigious Society. In The Unlikely Event That An Installed System, Vrv Or Otherwise, Were To Injure Or Kill Someone, Is A Major Issue. We As Contractors Are Entrusted By Our Customers To Do Everything Possible To Ensure That Our Work Will Not Harm Them.
Here You Could Install Vrv For 10 Years. Install Tens Of Thousands Of Systems Without A Problem. But The Day That The Inevitable, Unlikely, Accident Happens.you Have A Major Legal Problem On Your Hands. The Whole Distribution, Sales And Installation Chain Will Be Sued. The End Result, In Addition To Monetary Compensation For The Loss, Could Be That Every System Might Have To Be Repurchased Or Every Room On Each System Would Have To Be Refitted With A Leak Alarm System That Automatically Dials For Help And Vents The Room.

The Last Thing Any Industry Should Do, Is Consult A Manufacturer About Serious Safety Concerns And Expect Anything As An Answer Other Than A Self Serving Reply.

Thanks For Your Comments,

Ralph Feria

FreezerGeezer
22-10-2004, 05:13 PM
Ralph, why are all your words capitalised???? :confused:
If you think about a standard supermarket install, there can be several hundered kilos of refrigerant in the system (I once had to put 20-odd large bottles of R22 into a pack after a leak just to get the L.P. to stay in! It took a lot more to get the pack running right.). No-one has ever died due to a refrigerant leak in a supermarket, to the best of my knowlege, and I'd expect an A/C VRV system to have a lot less refrigerant than any old - style Tesco or Sainsbury pack system?
On the other hand, if you need to cover yourself for any possible legal action, then with all the safety gear that's going to be one HUGE sale ! :D :D

rbartlett
22-10-2004, 05:51 PM
Ralph, why are all your words capitalised????
If you think about a standard supermarket install, there can be several hundered kilos of refrigerant in the system (I once had to put 20-odd large bottles of R22 into a pack after a leak just to get the L.P. to stay in! It took a lot more to get the pack running right.). No-one has ever died due to a refrigerant leak in a supoermarket, to the best of my knowlege. I'd expect an A/C VRV system to have a lot less refrigerant than any old - style Tesco or Sainsbury pack system.
On the other hand, if you need to cover yourself for any possible legal action - then that's going to be one HUGE sale with all the safety gear! :-D

I remember a westward engineer in a supermarket due to a refrigeration leak..he was working on a freezer well when he was overcome by oxygen starvation (R22)
can't find any info but will post to fridgeman as i know ex-westward guys/gal post there


secondly I also remember back in '99 that we had regulations of this very thing as we had to put vents in the doors to overcome the % mix of refrigerant/air
I wasn't involved with the job but i remember hearing about it..again I can't find any details

I'm trying to dig out some info :-/

cheers

richard

ralph feria
22-10-2004, 08:58 PM
Dear Richard,
My Concern Is Oxygen Displacement. Children In Cribs And People In Situations Like Nursing Homes Are At Greatest Risk. I Have A Hard Time Understanding How Such A Huge Risk Is Taken So Lightly.

My Key Board Is Locked In Caps.

Ralph

rbartlett
22-10-2004, 09:28 PM
You would need to be in quite a sealed enviroment in order to get the symptoms you fear..

Recently I was working at a place which had a fairly major leak and when I was in the coldroom looking I found that I was going quite giddy and got both me and my assistant out..

(However I did note that he was far less aware and hence concerned than I and thought iId over reacted.However when he was feeling whoozy he understood why i got us both out )


In non refrigeration area i have never heard of any incidents of this happening...

Cheers

Richard

chemi-cool
22-10-2004, 09:34 PM
Hi Ralph.

I think you are over worried.

If it was so dangerous, your government would come out with new strict regulations of how to protect people in such environment.

I warm my house with 4 mini splits all winter and all the windows are closed and just like me are hundreds of thousands people in this country and millions others all over the world. I never heard of any problems. Did you?

Chemi :)

Brian_UK
22-10-2004, 11:49 PM
I seem to remember that the installation and design literature supplied with VRV/VRF systems mentions the requirement to be aware of the dangers following a leak in the system.

The manufacturers have taken notice of the fact and have passed it on to the designer/installer to ensure a safe system.

The use of door/wall ventilators, ventilation systems etc to dilute any leak are generally what is needed.

Check the size of the smallest room and calculate to contamination; ask yourself does it need ventilation ?

As as been mentioned before most leaks tend to be small in A/C internal units and the chance of a really dangerous buildup of refrigeration I would think to be unlikely. I accept that if it can go wrong then it probably will so always look on the worst case scenario.

ralph feria
23-10-2004, 12:01 PM
Dear Brian,
I Have Read The F-gas Regulatory Proposal. Hopefully The Final Draft Will Address My Safety Concerns. I Agree That A Small Leak, As Is Usually The Case, Is Not Of Great Concern. In 35 Years In The Business I Have Only Seen Three Ruptured Evaporators That Caused A Rapid Complete Dump Of The System Refrigerant Charge. I Saw One In An R-22 System More Than Twenty Years Ago. This Year I Have Seen Two. Both Were In R-410a Systems. Maybe The New Refrigerants And The Higher Working Pressures Have Something To Do With It.

Can You Tell Me More Of What It Says On The Installation Instructions? Sounds Like "cya".

Ralph

rbartlett
23-10-2004, 12:39 PM
bugger

i've been looking all over for that -and i find you had it all along!

cheers

richard

lin
24-10-2004, 03:58 AM
ASHRAE has a standard about safety in mechanical refrigeration. standard 135???
i have the 1994 version, there maybe a 2002? version on its website now.
in my unsure memory of that, nursing building is a more critical case in that standard.

if you want a copy of that, give me a email.

ralph feria
24-10-2004, 01:25 PM
Dear Marc,
Thanks For The Copy Of Bsen-378. Do You Know How Long Ago This Was Written? I Believe R-410a Is An Anesthetic And Is Heavier Than Air. The Lower Half Of The Room Could See Higher Concentrations Of Gas Than The Upper Part. I Dont Think These Two Points Were Addressed When The Standard Was Written. It Assumes A Homogenous Mix Of Air And Gas In The Space. Can We Keep This Thread Going Until We Reach A Conclusion??

Ralph

rbartlett
24-10-2004, 02:58 PM
the whole of R22 is heavier than air and will suffocate you due to oxygen displacement.

the 'conclusion' on this side of the pond is that VRV's have been used here since the early eighties and no recorded incidents thus far..

whilst this in itself in not a g.tee -what is??

Iwhere do you actually want the conclusion to end??

cheers

richard

ralph feria
24-10-2004, 03:37 PM
Dear Richard,
This Is A Dangerous Misapplied Technology. It May Be Good For Commercial/freezer Application But It Has No Place In The Bedroom.time Will Tell How It Will End. Be Patient.

Ralph

rbartlett
24-10-2004, 03:57 PM
As I thought -you have already made up your mind long before you came here..you seem to have a closed mind, which is a pity

basically you don't want to hear anything other than 'its dangerous' even though we have been using it since 1985 and the japanese even earlier

how 'patient' should we be??

there are already giudelines in place on the application for VRVs
virtually evey air conditioned hotel complex in the UK uses VRV systems..

eventually maybe possibly an accident may occur..but-


-------------------------------------------------

*lifted from a health and safety report*


First the bad news in this year’s report,which is based on 1999 data: the toll of accidents caused by tea cozies was up again, with a national estimate of 37 teacosy injuries, compared with 20 the previous year.


------------------------------------------------------
get over it-you either listen to what those who have had experience with these -all round the world- or you don't

either way this is the last on this from me..

stick to wind and tin central air..you can't help some people ;-)

cheers

richard

Latte
24-10-2004, 06:13 PM
Hi Guys,

How about this idea for all you system designers out there.

Make up a gas lead detector that can be wired to a (or pair) of llsv's so that if it picks up a leak it automaticly shuts off the gas to the unit.

Personally, i think there would not be enough of a market for it.
Like many others, the risk of a big leak on indoors units and big enough to cause oxygen depletion is so low that i couldn't see the point.

i am sure we could all come up with extra safty features to fit on units but you have to stop somewhere.

If anyone finds out a case where people have been injured by a leaking indoor unit i would like to hear about it. I however think it is mostly just people who worry about anything who panic about this.

Just do the job right on the install, pressure/strength test the system and get on with it

Regards

Fatboy

frank
24-10-2004, 07:05 PM
Make up a gas lead detector that can be wired to a (or pair) of llsv's so that if it picks up a leak it automaticly shuts off the gas to the unit.

Would that be a LLSV for each indoor unit then Raymond?

The whole point about refrigerant leaks into an occupied space with a VRV unit is that, as the system can hold large amounts of gas (we've been repairing one with 68KG's) and a leak anywhere on the system can that can dump the whole charge in a very short time, depending on how large the leak is must be monitored. EN378 requires that any system that can dump it's charge into a space and exceed the safety limit for concentration of refrigerant gas must have a monitoring and alarm system installed. Anything else and it does'nt conform to the regulations

Latte
24-10-2004, 09:36 PM
Hi Frank,

My idea was only for indoor units in small enclosed spaces (Bedrooms) i certainly wouldn't put one in hall, hallways.

Don't get me wrong, i don't see the point of fitting them, but i was just trying t come up with a solution for the guys that seem to panic all the time about gas leaks.

Regards

Raymond

ralph feria
25-10-2004, 04:50 AM
THE VOICE OF REASON APPEARS!!





Would that be a LLSV for each indoor unit then Raymond?

The whole point about refrigerant leaks into an occupied space with a VRV unit is that, as the system can hold large amounts of gas (we've been repairing one with 68KG's) and a leak anywhere on the system can that can dump the whole charge in a very short time, depending on how large the leak is must be monitored. EN378 requires that any system that can dump it's charge into a space and exceed the safety limit for concentration of refrigerant gas must have a monitoring and alarm system installed. Anything else and it does'nt conform to the regulations

Brian_UK
25-10-2004, 07:00 PM
THE VOICE OF REASON APPEARS!!
We have already given the requirements when dealing with these systems and Frank is simply reiterating that fact :confused:

FreezerGeezer
25-10-2004, 07:37 PM
I stick with my earlier post - this looks like a good opportunity to sell the client on the most advanced possible solution that meets their & the law's needs. I'm seeing an increasing number of our clients asking us to install fixed leak detectors in enclosed plant rooms, just in case. My philosphy is that it's always best to install the most advanced system that the client can afford. After all, how many times have we heard 'The air conditioning doesn't work like it should AND it's costing a fortune to run!' and the answer we'd like to give is 'If you'd spent the money we told you was required on a proper system, it would work like you wanted. Instead, you got a basic split system!' ;-)

ralph feria
25-10-2004, 08:49 PM
To All Who Have Participated In This String,

I Was One Of The Original Contributors To Daikins Vrv Design Project From 1980 To 1986. These Are Highly Engineered Very Vesatile Systems. I Spent 6 Months In Osaka Japan And Daikins Neighboring Factorys Of Shiga, Rinkai, And Kanaoka.as A Result I Know These Systems Quite Well. Maybe Even Better Than Any Of You. I Know What The Concerns Were Then And What They Are Now. Twenty Years Ago The Marketing Guys Were Very Concerned About The Installed Costs Vs Safety Issues. Bottom Line Is That Once You Incorporate The Leak Detectors And The Venting That Should Be In Small Rooms And In Rooms With People That May Not Be Able To Get Themselves Out In The Event Of A Discharge The Installed Cost Is Unworkable When Compared To Other Available Technology. I Am Glad To Hear From All Of You That No One Has Been Hurt By These Systems.hopefully No One Will. I Will Be Making Sure That The Proper Measures Are Taken Here To Safeguard The Occupants Where These Systems Are Installed.

Best Regards,
Ralph Feria

Thom101
09-12-2004, 05:05 PM
just going back to maximum concentrations of R410a in a room in the event of a leak.
i have a CIBSE document that states

" the maximum concentration levels that could reasonably be expected to occur if the system was subject to a catastrophic leak would be 0.44kg/m3 (R410a) or 0.31kg/m3 (R407c)"

to me this sounds like a guide, not a legal statement.

does anyone have definitive maximum concentration values for varying refrigerants?

PS
have designed and installed dozens of Daikin VRV's including the first VRVII in the UK. as far as im concerned they are fabulous systems, the only problems we get include unhappy clients getting on the phone because there system isnt heating! every single time this happens its always the defrost cycle of the condensers. find a way to stop the defrost cycle and then they will be god!

Peter_1
09-12-2004, 08:29 PM
.....Maybe Even Better Than Any Of You. .....
Ralph Feria
Oh yes?????? :confused: :( :mad:
You must be a very smart boy.
As said in a previous post, a VRV or VRF is nothing more than a pack we install in a supermarket with that very big difference that we have to calculate it all ourselves and that every plant has to be re-designed.
Sometimes different evaporating temperatures, frequency controlled compressors, heat reclaim, hot gas defrost.....
Can't be said for a VRV.
Even a plumber - I have nothing against a plumber - with a 1 day course and no previous refrigeration knowledge can install it.
Can he install after a 1 day course a pack with all his components? No.
Murco (Ireland) has developed a low-cost gas detector, special for such applications like VRV or packs where lots of gas can escape in rooms which are occupied

BritCit_Juve
10-12-2004, 12:39 AM
While it should be unlikely that a leak would occur in the systems that are installed and tested to the highest standards by well trained and motivated contientious engineers, what with pressure testing and vacuum holding they do unfortunately occur on occasion. If the room is small then the gas concentration can be excessive when a 20kg+ charge is dumped into it.
Toshiba are currently recommending the use of Refrigerant leak detectors in rooms that if the full system charge was decanted into it reached a level of 0.3kg/m3 or greater.
If the room is critical then you could fit shut off valves in both the gas and liquid lines, shut by the leak detector when a leak is detected.
Most HVAC supppliers have available room leak detectors and Toshiba even supply one.

BritCit_Juve

Peter_1
10-12-2004, 09:52 AM
PS......they are fabulous systems, the only problems we get include unhappy clients getting on the phone because there system isnt heating! every single time this happens its always the defrost cycle of the condensers. find a way to stop the defrost cycle and then they will be god!
So, they aren't that fabulous at all... especially in these days when you need the heat.
I mentioned this already in this forum...we installed one - it was a VRF from Mitsu but that doesn't change anything - in our own offices and even after 1 year, we placed an additional gas burner, installed duct heaters bewteen the ducts, fed with the hot water from the gas heater and use the VRF only for cooling.The comfort level was too low, running costs too high,...

In my own house, I installed 15 years ago an air/water HP, ...after 2 years, we replaced the HP for a gas heater. The running costs were too high. I know what I'm doing so it was easy for me to modificate certain items but even then, it was not worth to let it run.

Thom101
10-12-2004, 11:39 AM
Sounds to me like someone made a miscalculation in sizing the system! gas burners and ducts shouldnt be needed, surely?!
Did you get the electric heaters with the indoor units?
it is reconmended when you buy Mitsi.

Peter_1
10-12-2004, 12:10 PM
Sounds to me like someone made a miscalculation in sizing the system! gas burners and ducts shouldn't be needed, surely?!
Did you get the electric heaters with the indoor units?
it is reconmended when you buy Mitsi.

There was no miscalculation at all - they warmed the offices very well - and regarding to your answer, you don't see what's my point and have not enough experience with these units:

1. it were duct units so we needed ducts.

2. It's a VRF systems, so there are no heaters in the indoor units. They even can't be purchased with heaters.

3. In the other Mitsu (Mr Slim) units, there are heaters inserted but when this units defrosts - let's say a 5 kW unit - the electrical heater is somewhat 1,5 kW and far too less in capacity to compensate the cold of the indoor unit when defrosting. You always feel a cold falling out of the unit. Sometimes the fan then runs on a very low speed and adds to the cold feeling when the unit defrost.
We heard this complaints already more than 100 times and experienced it now ourselves.

4. If the unit should have a heater equal to the cooling capacity of the coil, ever thought what a defrost cycle then should cost?

My point was: we calculated it correct - we did already jobs with 8 VRF-R2 and more than 40 indoor units, we make our own packs, so whe know what we're doing - but it's the running cost of all these systems.
They run with a very bad COP despite the figures you find in the catalog's (recalculate once for yourselves the COP with a given cooling capacity and the needed power supply on that moment)
In these figures, they even haven't included the defrosting cycles (which occurs every 30 to 40 minutes and last some minutes) The COP then drops dramatically below the given figures.
Recalculate once for an outdoor temperature of 0°C and indoor 22°C the COP.

With the electricty cost we have here in Belgium (+/- 0,175 €/kWh), as soon outside temperatures drops below 5°C, it's not economical anymore to let run a heatpump. That's my opinion and were also my measurements.

chemi-cool
10-12-2004, 03:24 PM
Hi Peter.

How come you pay per KW 2.5 times then us?
Your government is cheating on you.

If you work out the voltage drop on an electric cable 3800km long, I can sell you cheap electricity. :D

Chemi :)

Thom101
10-12-2004, 04:45 PM
fair enough peter. good point well made.

Peter_1
10-12-2004, 09:49 PM
Hi Peter.

How come you pay per KW 2.5 times then us?
Your government is cheating on you.

If you work out the voltage drop on an electric cable 3800km long, I can sell you cheap electricity. :D

Chemi :)
The company who generates, delivers and send the invoices is a very big private owned company here (a lot of the stocks are in the hands of French peoples), Electrabel.
Due to new EU regulations, they were forced to allow others to sell also electricity who then could use (or hire) the installations (high tension lines, transformers, ..)
So, what did Electrabel: other companies came but if you looked to the roots, it still remained Electrabel.
Some others came but they had to hire the lines at very high prices.
France companies even tried to deliver electricity to Belgium via the existing high tension lines but the lines along the French border weren't calculated for this additional power and it should take years to install new ones or bigger ones,.. so.. France couldn't deliver electricity.

There is no competition here, same for the phone, train, public transport, water delivery, gas delivery, television distribution,...
No competition means high prices and mostly a bad service.

If you need information, you only can call a paying number (+/- 0.5 €/minute) It take mostly 10 to 15 minuets before you reach the right person.

You contact the phone company: all our employees are busy for the moment, you're number 6 in the cue, please hold the line. It can take 30 minutes before someone picks up the phone.
Shutting down the line wont help, if you retry you get the same message.

If a new factory wants to start here with a new plant, then after you filled in the necessary papers, it will take even then 4 months before they will deliver electricity.
You have to count +/- 25.000€ for a high tension transformer and you hire then afterwords the transformer..
Electricity is then also a lot cheaper as long as you stay a big consumer: something around 0.05 €

Same for water: 2 to 3 months waiting.

Only the mobile phones, where we have 3 competitors.

A few years ago, the phone company got also some competition because the cable distribution installed a new system whereby it was possible to make calls along their television lines.

frank
10-12-2004, 10:12 PM
We always think that the grass is greener on the other side but it appears that it's just the same no matter where you live :)

PobodysNerfect
10-12-2004, 11:43 PM
We always think that the grass is greener on the other side but it appears that it's just the same no matter where you live :)

Humm, you also pay less than 0,04 euro for a liter of petrol?

Peter_1
11-12-2004, 09:28 AM
We pay +/- 0.4 €/l for petrol for heating purposes (they color it here red because the added taxes are not that high than the petrol for automotive applications) and +/- 1 € for automibile applications (not colored)
Fuel lead and unlead = +/- 1.2 €/l.

windy
24-04-2006, 10:44 PM
I have a copy of a Daikin extract of BSEN378 that lays down maximum exposure/room volumes it is 1.08mb so I cant post it but will email if it helps
Rgds
Windy

ralph feria
25-04-2006, 03:13 AM
DEAR WINDY,

THANKS FOR YOUR REPLY. PLEASE EMAIL THE EXTRACT TO ME AT RALPHF@MULTIAQUA.COM. DAIKIN HAS COME OUT WITH A VERSION III (3) THAT IS SUPPOSED TO ADDRESS THE MECHANICAL SAFETY CODE ISSUES BY PUTTING REFRIGERANT SENSORS IN ALL THE FANCOILS. WHEN TRIGGERED IT IS SUPPOSED TO SHUT A SOLENOID VALVE AT THE FANCOIL AND PUMP ALL THE REFRIGERANT IN THE SYSTEM BACK TO THE CONDENSING UNIT.

THANKS AGAIN.

RALPH

rbartlett
25-04-2006, 06:22 AM
still got that dodgy keyboard eh? still Good to see you back Ralph -stay and post

cheers

richard

krychek
12-06-2006, 07:43 PM
Hi Ralph,

We have within the UK a directive from the EU called EN378, which highlights the need or negates the need for leak detection within occupied space particulary whilst the occupant is sleeping, perhaps if you could get your hands on a copy of this and maybe put these parameters in place as 'good pratice' before you go spending a load of dollars on expensive leak detection systems