I tried to post this last night, but it appears to have gone into the abyss. If it's out there and doubled up let me know and I'll delete one, but I can't find it.
Anyway......I don't believe this would be common knowledge to people and I shudder to think of the different circumstances this could have been - i.e. me asleep and not having any warning. I don't know whether this info is contained in the manuals as i had difficulty bringing it up online at the time it was happening and I am now away from my van in a hotel room to be able to check.......but if you smell ammonia in your van/MH and you have a 3 way fridge....get the heck out.
My fridge began to lose chill the other day so I organised to tow it 40klm to meet with the repairer (Luckily mine, as I'm part way into crossing the nullabor via Hyden too!!). Long story short...when I got to where I was going to meet him, I opened the van and was hit with a strong whiff I couldn't identify for a second - I then recognosed it as ammonia....wondered what in earth I could have on board with that in....commenced searching for hair dye etc in case something was leaking and having a reaction. So I was breathing this all along. I left and googled 'refridgerant odour' which came back as 'freon (used in compressor fridges only) and that it was odourless. So I commenced searching again, wondering what on earth could go wrong next. Still no luck - realised the smell was worse in the cupboards around the fridge (still breathing it in). Retreated to Google more specifically 3 way fridge gas and bingo!! Ammonia!!! Very dangerous stuff. I still have a headache. I wasn't allowed to sleep in the van last night and possibly tonight if it hasn't gone. I don't know what you'd do if you were out in the bush. And shudder, like I said asleep!!!!!
So moral off the story is....keep in mind that's what a fridge leaking smells like. I had no idea and I consider myself fairly switched on at most things caravan. I'm sure there would be a lot of people out there that don't know this, nor how dangerous it is.
Hope today's better - I was robbed that day to - I was just about to call it quits and move to a nursing home lol
cheers
grob
iana said
11:57 AM Oct 13, 2016
An interesting comment, but I consider ammonia to be one of the safer gases used as a refridgerant. The main reason for this is the fact you can smell it, and the human bodies tolerance to the smell is so low, that one cannot stay in the area, even though the air ammonia concentration is nowhere near fatal.
On the other hand Freon is odourless, as so you can be there and the atmosphere is becoming poisonus and you wouldn't be aware.
To die because of ammonia, you would have to be trapped in a space.
I've had some pretty good doses, and I am still here.
Aus-Kiwi said
12:16 PM Oct 13, 2016
Yes you have to be aware of many things . Like you I think I'm tech enough to work things out or Atleast know to leave to someone who does ., But even with new equipment., You STILL need to keep servicing things .. Like there's plenty of service centres in Nullabor !! Best part is removing it out of van !! The door is often smaller than fridge .. Ahh through window !
macka17 said
12:35 PM Oct 13, 2016
Compressor fridges only.
There's no comparison.
I have yet to figure out why caravans have these huge Household size fridges in them.
2 people.Travelling.
Has anybody stopped to think how much a full, Full sized fridge can weigh??.
And so many whinging about being near max and over weight.
Makes you think.
I never have more than the stock 90ltr size. along with the Waeco in ute.
We last a week comfortably on them. with minimal weight.
and the Waeco. if used as freezer. Is good for a coupla months volume.
easy.
Grubbygypsy said
12:50 PM Oct 13, 2016
Well....I'm asthmatic so it's maybe a bit worse for me (although I had no asthma symptoms from it). I just wonder what would happen though when you're asleep? (Due to the fact you can't smell in your sleep - hence how people die in their sleep in house fires). I reckon you'd be pretty crook if you took it in for an extended period.
Glad to know I won't be carking yet. I phoned poisons info - as I was also concerned for food in surrounding cupboards, in case it leaves a residue. No one seemed to know, including the MSDS, a lot of unknowns on there.
What service is required with a fridge AUS-Kiwi? I must have missed something somewhere.
Yes....it has to come out through the window. It still stinks this morning now I'm back from the hotel, so unless it's removed today, I'll have to go back to the hotel. I'm still waiting on this mornings update.
Explorer said
01:19 PM Oct 13, 2016
Grubbygypsy wrote:
Well....I'm asthmatic so it's maybe a bit worse for me (although I had no asthma symptoms from it). I just wonder what would happen though when you're asleep? (Due to the fact you can't smell in your sleep - hence how people die in their sleep in house fires). I reckon you'd be pretty crook if you took it in for an extended period. Glad to know I won't be carking yet. I phoned poisons info - as I was also concerned for food in surrounding cupboards, in case it leaves a residue. No one seemed to know, including the MSDS, a lot of unknowns on there. What service is required with a fridge AUS-Kiwi? I must have missed something somewhere. Yes....it has to come out through the window. It still stinks this morning now I'm back from the hotel, so unless it's removed today, I'll have to go back to the hotel. I'm still waiting on this mornings update.
Ammonia has a low boiling point, water has a much higher boiling point so neither are suitable as a refrigerant. Combine the two and You have the ideal refrigerant, the only problem is that the water can rust the pipes & cause a leak.In a lot of cases the pipes can be repaired whilst still in the van or removed & repaired/replaced without removing the fridge. A specialist absorbtion refrigeration Tec won,t have a problem with a repair like that.
At the worst He/She will move the fridge into the floorspace, rotate it & work on it in the doorway.
Mike.
-- Edited by Explorer on Thursday 13th of October 2016 01:24:07 PM
Brenda and Alan said
08:29 PM Oct 13, 2016
Ammonia on its own is an excellent refrigerant and was used for many years in compressor type refrigeration. It was replaced by the newer cloroflouro hydrocarbons because of the danger when leaks occurred in large refrigeration plants like cool rrooms and meat works.
Absorption fridges work on an entirely different principle and can use a mixture of water and ammonia as the refrigerant, however internal rusting is not a problem as there is no oxygen present in the mixture. Iron needs both oxygen and water to rust and will not rust in the presence of only one. So any breach in the piping of an absorption fridge is either a crack from stress or external rusting.
Alan
Aus-Kiwi said
08:59 PM Oct 13, 2016
H2O sorry to be a nark lol . I assume water doesn't evaporate ?
-- Edited by Aus-Kiwi on Thursday 13th of October 2016 09:00:26 PM
Brenda and Alan said
08:22 AM Oct 14, 2016
Graeme the water doesn't evaporate the ammonia does. The heating element drives the ammonia out of solution in the water and it is the ammonia that goes through the refrigeration cycle and is then reabsorbed into the water away from the heat source. convection then carries the ammonia rich solution to the heat source and the cycle is continuous. All early domestic fridges used this system aka kerosene fridges.
Alan
Grubbygypsy said
09:44 AM Oct 14, 2016
I hardly see what the size of the fridge has to do with anything. Not sure I even mentioned it. I'm not an SAS (Saturday and Sundays) traveller, so I have as larger fridge as *I* (WOW and there's only ME) to travel for the durations *I* want. On second thoughts.....I'm listing my van for sale and going to hunt down my old L300 seeing Macka thinks it's a better way for me to be travelling.
I also don't overly care about how the fridge works or how good they are.
The point of my post was - if you smell ammonia in your van/MH - don't stay around breathing it in thinking you've got something else leaking. It's your fridge. I hope someone is aided by the knowledge of what a 3 way fridge smells like when it goes off. Had I known I woulda got out of there sooner, rather than looking for other offenders.
Hope someone got my point!!!
iana said
10:39 AM Oct 14, 2016
Thankyou Grubbygypsy for posting the warning. I now know how a 3 way works, which I didn't before now.
Grubbygypsy said
11:49 AM Oct 14, 2016
Onya iana. That was all I was trying to do. Maybe I should have known before and found the intricacies of the fridge out. But out of three vans and many years of travelling, I didn't know. So I'm betting there are 1000s of people out there that don't know.
vince56 said
02:09 PM Oct 14, 2016
Hey Macka,
90 liltre in your van, Waeco in the cute, mate sounds like YOU carry a fair bit anyway!
Compressor fridge may suit you, like your beloved Patrol, but what suits you may not suit everyone.
Dickodownunder said
09:03 PM Oct 14, 2016
Thank you for the warning and the description Grubbygypsy.
Do you know how old your fridge is?
Reason I ask is that I am wondering if new 3 way fridges still use ammonia?
Maybe someone will know.
woofta and precious said
09:17 PM Oct 14, 2016
Vince56
Yep, I like ice cream, ice cubes, frozen meals (weight watchers of course) bread and meat I can get cheaper before I leave on a trip to freeze. And then there is the BEER, SPIRITS, MILK I like on my cereal, soft drink, Fruit and Vegies, fruit juice, yoghurt, cheese, butter etc.etc. We used to travel with just a car fridge, but now have a van with a 218 litre fridge AND a car fridge! We now just get by....
Grubbygypsy
Even though we have compressor fridges, it is very handy information in case someone else has a problem that we know or camp with.
Tony Bev said
10:06 PM Oct 14, 2016
Yes Grubbygypsy I got your point, and thanks for posting the info
DeBe said
10:36 PM Oct 14, 2016
All 3 way fridges use ammonia.
NeilandRaine said
11:01 PM Oct 15, 2016
Just an aside, 3 way fridges only freeze to minus 12, for ice cream to stay hard you need minus 18. Or so I have been told.
I know Ice cream is always soft in our 3 way
And thanks for the warning.
A good friend of mine lost two grand children because of this, He was visiting and the kids wanted to sleep in the van, they swapped beds
and the rest is history.
Grubbygypsy said
12:50 PM Oct 21, 2016
Dickodownunder wrote:
Thank you for the warning and the description Grubbygypsy.
Do you know how old your fridge is?
Reason I ask is that I am wondering if new 3 way fridges still use ammonia?
Maybe someone will know.
Sorry for my delay.....I've just had the fortnight from hell....including the death of a granddog that I got the blame for......
The fridge was as old as the van - 5.5 years. It was the AES Dometic. I called Dometic over the safety of the rest of the food ie does the ammonia have a residual, and he sounded genuinely surprised that the fridge had blown up to be honest.
Its now finally replaced and I'm just restocking to hit the road again. I'm unsure if they still have this....I'm assuming yes, as it's how they work...ie 'gas conversion'.
I was also robbed in this period.....so I'll take all the prayers I can get, that when I hit the road tomorrow, I don't get T boned by a roadtrain....
Grubbygypsy said
12:56 PM Oct 21, 2016
NeilandRaine wrote:
Just an aside, 3 way fridges only freeze to minus 12, for ice cream to stay hard you need minus 18. Or so I have been told. I know Ice cream is always soft in our 3 way And thanks for the warning. A good friend of mine lost two grand children because of this, He was visiting and the kids wanted to sleep in the van, they swapped beds and the rest is history.
OMG!!!! That is horrific!!
see.......I knew I was concerned about the smell of it (I was ill for 1.5 days just from the hit I got) and being around it during sleep. Hence my warning.
I am so sorry for your friend.
I am not feeling quite as bad about my little granddog after reading that!!!! (It was in no way my fault, but they've chosen to blame me).
Gee...life can be cruel.....
Bill B said
08:05 AM Oct 22, 2016
NeilandRaine wrote:
Just an aside, 3 way fridges only freeze to minus 12,
Don't tar all 3 way fridges with the same brush.
Yours may only get to -12c but mine and many others get much colder than that and have no trouble keeping ice cream hard.
laurieoz said
08:27 AM Oct 22, 2016
Mine has been minus 24 0C many times - I now use a thermometer in the freezer and one in the fridge compartment that transmits temperatures to a receiver so I know the temperatures and can adjust the temperature
Hylife said
05:11 PM Oct 22, 2016
Sorry but this story is just so much "old wife's tale". (read that as bullsh!t).
The quantity of ammonia in an absorption (3way) fridge is so very small. The human nose can detect the smell of ammonia as small as a 5 parts per million. To us humans it has a VERY strong smell. Strong ammonia smells are used to wake faint victims. If your fridge is leaking slowly the smell seems to linger for a long period. Even in instances where the leak is large and the escape is very quick, in no way would it pose a threat to your health unless you stuck your nostrils right up to a hole in the pipework and at the exact moment you pierced the pipe you inhaled all the expelled gases or stuck your eye in front of the expelling gases.
Liquid ammonia expands to 850 times it volume under 1 atmosphere pressure. The amount of pure liquefied ammonia in a 90 litre 3way fridge is approx. quarter of a litre (250ml). On release this expands to 213 litres. An amount of gas equal to only approx. 2.5 times the interior size of your fridge. Anhydrous (no water) Ammonia gas has a tremendous affinity for water and reacts immediately with humidity in the air and becomes hydrous ammonia which is heavier than air and will remain close to the ground. The Ammonia in your fridge is already hydrous. Ammonia leaking from your fridge will remain mostly at floor level and disperse out your van door safety vents. If released all at once in a 16 foot van it would result in approx. 1 inches (25mm) of hydrous ammonia gas on the floor of your van and yes it will have you coughing and spluttering but within a few minutes would have poured out the safety vents in the van door. A slow leak in your fridge over a few hours may result in an extended strong smell of ammonia but the concentrations are tiny and within a couple of hours your fridge's pressurised system would have equalised and no longer be leaking.
Your first pee in the morning smells strong because of ammonia. On a cold morning a standing man will inhale more ammonia from his pee than you would get from your average slow leaking fridge. Ammonia based fertiliser known as Urea, gets its name from Urine. In US conducted safety tests, some individuals exposed to 50 parts per million (ppm) over 10 minutes have experienced mild respiratory irritation, but it takes 500 ppm over 30 minutes to alter your respiratory rate, 1700ppm to induce coughing, and 6000ppm over 2 hours can produce burning in the eyes, nose and mouth and produce progressive cyanosis (lack of oxygenated blood) and eventually death. The maximum recommended safe exposure is 50ppm over an 8 hour period.
Ammonia is used in a myriad of household products that we use every day with no detrimental effects (unless you misuse the product such as prolonged sniffing of detergents such as Domestos or Handy-Andy).
For those that have ever wondered how an absorption fridge works I'll try and explain their operation in layman's terms. Purists please excuse my over-simplification.
During manufacture the system is first reduced to an almost complete vacuum and then the system is filled with mostly pressurised hydrogen and water and a quite small amount of pure liquid ammonia. The hydrogen pressure is set to the point where ammonia boils, based on the maximum ambient temperature the fridge must operate in. Ammonia normally boils from liquid to a gas at minus 33 degrees Celsius. For a 'tropical' rated fridge, at plus 35 degrees Celsius (maximum ambient temp), the dew point of ammonia (the point where it changes form from a liquid to a gas or back to a liquid) is at a pressure of approx. 200psi or around 14 atmospheres of pressure. The electric heating element (12V or 230V) or the gas pilot flame, is located at the bottom of the pipework and heats the 3 ingredients to a temperature greater than the 35 Celsius ambient (the dew point of the ammonia) and it changes to a gas, bubbles out of the water, up the pipe work and increases the system pressure. As the hot gas passes over the pipework at the top that looks like a radiator (condenser) it cools (condenses) back to a liquid and the pressure drops. Just like you have experienced on the outside of your gas bottles when they run low, when the pressure drops it gets cold. The colder liquid ammonia flows downward it passes through pipework inside the fridge and absorbs heat from inside the fridge as it goes (this is why it is called an absorption fridge). Cold doesn't radiate coldness, heat radiates heat, cold absorbs heat. It then re-mixes further down the pipework with the water and flows back to the heating area and the cycle repeats.
Roving-Dutchy said
05:37 PM Oct 22, 2016
Hylife
Thank you for such an informative and interesting post, I just hope that anyone who has been alarmed reading so much incorrect information, can now sleep easy at night after reading your post
Cheers
David
Grubbygypsy said
12:03 PM Oct 29, 2016
Unsure which part you're calling bull**** on? The fact that myself, my son in law and the repairer all suffered headaches for over 24 hours once this fridge went or the fact that some kids died.
FFS......I'll restate it for those that have difficulty with comprehension.....IF you smell ammonia in your van and you have a 3 way (most)...the refrigerant has let go. Try not to breathe it.......
I am so sick of NOCs on forums such as this. I just tried to warn people who might not know this is the smell of a fridge. Didn't expect to be called a bull****ter.
iana said
05:55 PM Oct 29, 2016
What Hylife has written is perfectly correct, re the ammonia. His statement just extends what I wrote in the second post. The simple fact is that if you smell ammonia in the RV, then its a leaking fridge. Because the human tolerance to the smell is so low you will want to get out of there.
I have only heard of one person dying because of ammonia, and that person was trapped in the room. I have worked with, and copped some very heavy concentrations of ammonia, and what happens is that you cannot breath in, the only way to be able to breathe is by forcing oneself to exhale no matter what state you are in, then breath in.
I worked in a large winery and I looked after 5 ammonia fridge plants, each having a 1 or 2 tonne tanks of liquid ammonia. I am still here.
There is probably more ammonia smell when women dye their hair, which I find amazing how they put up with it with out complaining.
mredge said
11:52 AM Jan 29, 2020
I think ammonia is a real concern for those of us that have older appliances. When I read the article about Wedge Island camping deaths this week (7news.com.au/news/wa/father-son-killed-by-fridge-gas-leak-in-wedge-island-camping-tragedy-c-668770) I immediately thought about previous reports of camping fridges letting go. This one might have been LPG. It is yet to be confirmed.
This article about ammonia seems to state the seriousness of exposure: resusreview.com/2014/ammonia-inhalation-injury/
Keep your fridges serviced folks, and don't mess about if there's external rust that might lead to a leak. My circa 1970's fridge has always been stored well and is in seemingly great condition but I'm having serious thoughts about getting rid of it.
I tried to post this last night, but it appears to have gone into the abyss. If it's out there and doubled up let me know and I'll delete one, but I can't find it.
Anyway......I don't believe this would be common knowledge to people and I shudder to think of the different circumstances this could have been - i.e. me asleep and not having any warning. I don't know whether this info is contained in the manuals as i had difficulty bringing it up online at the time it was happening and I am now away from my van in a hotel room to be able to check.......but if you smell ammonia in your van/MH and you have a 3 way fridge....get the heck out.
My fridge began to lose chill the other day so I organised to tow it 40klm to meet with the repairer (Luckily mine, as I'm part way into crossing the nullabor via Hyden too!!). Long story short...when I got to where I was going to meet him, I opened the van and was hit with a strong whiff I couldn't identify for a second - I then recognosed it as ammonia....wondered what in earth I could have on board with that in....commenced searching for hair dye etc in case something was leaking and having a reaction. So I was breathing this all along. I left and googled 'refridgerant odour' which came back as 'freon (used in compressor fridges only) and that it was odourless. So I commenced searching again, wondering what on earth could go wrong next. Still no luck - realised the smell was worse in the cupboards around the fridge (still breathing it in). Retreated to Google more specifically 3 way fridge gas and bingo!! Ammonia!!! Very dangerous stuff. I still have a headache. I wasn't allowed to sleep in the van last night and possibly tonight if it hasn't gone. I don't know what you'd do if you were out in the bush. And shudder, like I said asleep!!!!!
So moral off the story is....keep in mind that's what a fridge leaking smells like. I had no idea and I consider myself fairly switched on at most things caravan. I'm sure there would be a lot of people out there that don't know this, nor how dangerous it is.
Hope today's better - I was robbed that day to - I was just about to call it quits and move to a nursing home lol
cheers
grob
On the other hand Freon is odourless, as so you can be there and the atmosphere is becoming poisonus and you wouldn't be aware.
To die because of ammonia, you would have to be trapped in a space.
I've had some pretty good doses, and I am still here.
There's no comparison.
I have yet to figure out why caravans have these huge Household size fridges in them.
2 people.Travelling.
Has anybody stopped to think how much a full, Full sized fridge can weigh??.
And so many whinging about being near max and over weight.
Makes you think.
I never have more than the stock 90ltr size. along with the Waeco in ute.
We last a week comfortably on them. with minimal weight.
and the Waeco. if used as freezer. Is good for a coupla months volume.
easy.
Glad to know I won't be carking yet. I phoned poisons info - as I was also concerned for food in surrounding cupboards, in case it leaves a residue. No one seemed to know, including the MSDS, a lot of unknowns on there.
What service is required with a fridge AUS-Kiwi? I must have missed something somewhere.
Yes....it has to come out through the window. It still stinks this morning now I'm back from the hotel, so unless it's removed today, I'll have to go back to the hotel. I'm still waiting on this mornings update.
Ammonia has a low boiling point, water has a much higher boiling point so neither are suitable as a refrigerant. Combine the two and You have the ideal refrigerant, the only problem is that the water can rust the pipes & cause a leak.In a lot of cases the pipes can be repaired whilst still in the van or removed & repaired/replaced without removing the fridge. A specialist absorbtion refrigeration Tec won,t have a problem with a repair like that.
At the worst He/She will move the fridge into the floorspace, rotate it & work on it in the doorway.
Mike.
-- Edited by Explorer on Thursday 13th of October 2016 01:24:07 PM
Ammonia on its own is an excellent refrigerant and was used for many years in compressor type refrigeration. It was replaced by the newer cloroflouro hydrocarbons because of the danger when leaks occurred in large refrigeration plants like cool rrooms and meat works.
Absorption fridges work on an entirely different principle and can use a mixture of water and ammonia as the refrigerant, however internal rusting is not a problem as there is no oxygen present in the mixture. Iron needs both oxygen and water to rust and will not rust in the presence of only one. So any breach in the piping of an absorption fridge is either a crack from stress or external rusting.
Alan
H2O sorry to be a nark lol . I assume water doesn't evaporate ?
-- Edited by Aus-Kiwi on Thursday 13th of October 2016 09:00:26 PM
Graeme the water doesn't evaporate the ammonia does. The heating element drives the ammonia out of solution in the water and it is the ammonia that goes through the refrigeration cycle and is then reabsorbed into the water away from the heat source. convection then carries the ammonia rich solution to the heat source and the cycle is continuous. All early domestic fridges used this system aka kerosene fridges.
Alan
I also don't overly care about how the fridge works or how good they are.
The point of my post was - if you smell ammonia in your van/MH - don't stay around breathing it in thinking you've got something else leaking. It's your fridge. I hope someone is aided by the knowledge of what a 3 way fridge smells like when it goes off. Had I known I woulda got out of there sooner, rather than looking for other offenders.
Hope someone got my point!!!
90 liltre in your van, Waeco in the cute, mate sounds like YOU carry a fair bit anyway!
Compressor fridge may suit you, like your beloved Patrol, but what suits you may not suit everyone.
Do you know how old your fridge is?
Reason I ask is that I am wondering if new 3 way fridges still use ammonia?
Maybe someone will know.
Yep, I like ice cream, ice cubes, frozen meals (weight watchers of course) bread and meat I can get cheaper before I leave on a trip to freeze. And then there is the BEER, SPIRITS, MILK I like on my cereal, soft drink, Fruit and Vegies, fruit juice, yoghurt, cheese, butter etc.etc. We used to travel with just a car fridge, but now have a van with a 218 litre fridge AND a car fridge! We now just get by....
Grubbygypsy
Even though we have compressor fridges, it is very handy information in case someone else has a problem that we know or camp with.
I know Ice cream is always soft in our 3 way
And thanks for the warning.
A good friend of mine lost two grand children because of this, He was visiting and the kids wanted to sleep in the van, they swapped beds
and the rest is history.
Sorry for my delay.....I've just had the fortnight from hell....including the death of a granddog that I got the blame for......
The fridge was as old as the van - 5.5 years. It was the AES Dometic. I called Dometic over the safety of the rest of the food ie does the ammonia have a residual, and he sounded genuinely surprised that the fridge had blown up to be honest.
Its now finally replaced and I'm just restocking to hit the road again. I'm unsure if they still have this....I'm assuming yes, as it's how they work...ie 'gas conversion'.
I was also robbed in this period.....so I'll take all the prayers I can get, that when I hit the road tomorrow, I don't get T boned by a roadtrain....
OMG!!!! That is horrific!!
see.......I knew I was concerned about the smell of it (I was ill for 1.5 days just from the hit I got) and being around it during sleep. Hence my warning.
I am so sorry for your friend.
I am not feeling quite as bad about my little granddog after reading that!!!! (It was in no way my fault, but they've chosen to blame me).
Gee...life can be cruel.....
Don't tar all 3 way fridges with the same brush.
Yours may only get to -12c but mine and many others get much colder than that and have no trouble keeping ice cream hard.
Mine has been minus 24 0C many times - I now use a thermometer in the freezer and one in the fridge compartment that transmits temperatures to a receiver so I know the temperatures and can adjust the temperature
Sorry but this story is just so much "old wife's tale". (read that as bullsh!t).
The quantity of ammonia in an absorption (3way) fridge is so very small.
The human nose can detect the smell of ammonia as small as a 5 parts per million. To us humans it has a VERY strong smell. Strong ammonia smells are used to wake faint victims.
If your fridge is leaking slowly the smell seems to linger for a long period. Even in instances where the leak is large and the escape is very quick, in no way would it pose a threat to your health unless you stuck your nostrils right up to a hole in the pipework and at the exact moment you pierced the pipe you inhaled all the expelled gases or stuck your eye in front of the expelling gases.
Liquid ammonia expands to 850 times it volume under 1 atmosphere pressure.
The amount of pure liquefied ammonia in a 90 litre 3way fridge is approx. quarter of a litre (250ml). On release this expands to 213 litres. An amount of gas equal to only approx. 2.5 times the interior size of your fridge.
Anhydrous (no water) Ammonia gas has a tremendous affinity for water and reacts immediately with humidity in the air and becomes hydrous ammonia which is heavier than air and will remain close to the ground. The Ammonia in your fridge is already hydrous. Ammonia leaking from your fridge will remain mostly at floor level and disperse out your van door safety vents.
If released all at once in a 16 foot van it would result in approx. 1 inches (25mm) of hydrous ammonia gas on the floor of your van and yes it will have you coughing and spluttering but within a few minutes would have poured out the safety vents in the van door.
A slow leak in your fridge over a few hours may result in an extended strong smell of ammonia but the concentrations are tiny and within a couple of hours your fridge's pressurised system would have equalised and no longer be leaking.
Your first pee in the morning smells strong because of ammonia. On a cold morning a standing man will inhale more ammonia from his pee than you would get from your average slow leaking fridge. Ammonia based fertiliser known as Urea, gets its name from Urine.
In US conducted safety tests, some individuals exposed to 50 parts per million (ppm) over 10 minutes have experienced mild respiratory irritation, but it takes 500 ppm over 30 minutes to alter your respiratory rate, 1700ppm to induce coughing, and 6000ppm over 2 hours can produce burning in the eyes, nose and mouth and produce progressive cyanosis (lack of oxygenated blood) and eventually death.
The maximum recommended safe exposure is 50ppm over an 8 hour period.
Ammonia is used in a myriad of household products that we use every day with no detrimental effects (unless you misuse the product such as prolonged sniffing of detergents such as Domestos or Handy-Andy).
For those that have ever wondered how an absorption fridge works I'll try and explain their operation in layman's terms. Purists please excuse my over-simplification.
During manufacture the system is first reduced to an almost complete vacuum and then the system is filled with mostly pressurised hydrogen and water and a quite small amount of pure liquid ammonia.
The hydrogen pressure is set to the point where ammonia boils, based on the maximum ambient temperature the fridge must operate in. Ammonia normally boils from liquid to a gas at minus 33 degrees Celsius.
For a 'tropical' rated fridge, at plus 35 degrees Celsius (maximum ambient temp), the dew point of ammonia (the point where it changes form from a liquid to a gas or back to a liquid) is at a pressure of approx. 200psi or around 14 atmospheres of pressure.
The electric heating element (12V or 230V) or the gas pilot flame, is located at the bottom of the pipework and heats the 3 ingredients to a temperature greater than the 35 Celsius ambient (the dew point of the ammonia) and it changes to a gas, bubbles out of the water, up the pipe work and increases the system pressure.
As the hot gas passes over the pipework at the top that looks like a radiator (condenser) it cools (condenses) back to a liquid and the pressure drops.
Just like you have experienced on the outside of your gas bottles when they run low, when the pressure drops it gets cold.
The colder liquid ammonia flows downward it passes through pipework inside the fridge and absorbs heat from inside the fridge as it goes (this is why it is called an absorption fridge).
Cold doesn't radiate coldness, heat radiates heat, cold absorbs heat.
It then re-mixes further down the pipework with the water and flows back to the heating area and the cycle repeats.
Thank you for such an informative and interesting post, I just hope that anyone who has been alarmed reading so much incorrect information, can now sleep easy at night after reading your post
Cheers
David
FFS......I'll restate it for those that have difficulty with comprehension.....IF you smell ammonia in your van and you have a 3 way (most)...the refrigerant has let go. Try not to breathe it.......
I am so sick of NOCs on forums such as this. I just tried to warn people who might not know this is the smell of a fridge. Didn't expect to be called a bull****ter.
I have only heard of one person dying because of ammonia, and that person was trapped in the room. I have worked with, and copped some very heavy concentrations of ammonia, and what happens is that you cannot breath in, the only way to be able to breathe is by forcing oneself to exhale no matter what state you are in, then breath in.
I worked in a large winery and I looked after 5 ammonia fridge plants, each having a 1 or 2 tonne tanks of liquid ammonia. I am still here.
There is probably more ammonia smell when women dye their hair, which I find amazing how they put up with it with out complaining.
This article about ammonia seems to state the seriousness of exposure: resusreview.com/2014/ammonia-inhalation-injury/
Keep your fridges serviced folks, and don't mess about if there's external rust that might lead to a leak. My circa 1970's fridge has always been stored well and is in seemingly great condition but I'm having serious thoughts about getting rid of it.