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Re: hotpoint larder fridrge
Question, please correct me if im wrong.
If a fridge or a freezer “lost” gas would it not be a “leak” that caused this?
Then it would obviously need to have the leak brazed/welded before you topped it up?
If it has got a leak wouldnt the compressor probably be cooked by now?Thx.
LeeRe: hotpoint larder fridrge
it could be internal pipe work too have regased loads over years. its supprisin how long they can last. must be tiny leak. can last years 😆
Re: hotpoint larder fridrge
Saw this thread and out of interest emailed Supco & Watsco asking them if their bullet valves are suitable for permanent connection to r600/r600a as it doesn’t mention HC’s on the adverts etc,wasn’t sure if the valve fitting was likely to create a weak point,would loc rings be more susceptible,possibly.
When you read the spec on manufactures site they claim they increase the strength of the pipe when fitted as the valve is clamped on,fairly obvious but perhaps a saliant point.
Also say they ae suitable for 410a on the high pressure side as well as the low so that would be a fair test.
Supco have already replied saying “yes theirs are suitable for permanent connection” to r600 systems.
Would have thought that a disclaimer on the fitting instructions for the valve would be necessary if they do represent a danger.
It’s difficult to find precise working instructions for r600 in general although ACRIB have an extensive list on the web and interesting room size limitations but don’t mention bullet valves.
Manufacture’s ogf r600 haven’t helped this trade by failing to supply safe working practice sheets,perhaps they are not sure which is the right way too. 🙂Re: hotpoint larder fridrge
OK lets try and clarify it if we can. We can agree that R600a is inflammable. We can also agree that if mixed with a quantity of air and has heat applied it can explode. Factually, 6 out of every 10 line tap valves that are applied to R600a systems leak – why do they, well its a combination of thin walled pipework, the refrigerant being very thin unlike R12 and R134a, poor quality (in the market) line tap valves and most importantly the fact that R600a systems during normal operation run in a vacuum of between 15-20hg – unlike R12/R134a which operate in a positive pressure.
Lets take a normal call out to an appliance that is short of gas – was it short of gas from day one or has it sprung a leak. You put on a line tap valve and top it up (or vac it out and recharge it) you then disapear thinking all is well. Over the next couple of weeks the line tap allows in a quantity of air (remember the system is working in a vacuum). This air causes an increase in compressor head pressure which increases the heat within the system – heat, fuel and oxygen = bang.Regarding the increase of strength once a bullet valve is clamped, I would disagree, from my experience the current Chinese manufacturered fridges have such thin walled pipework that it is difficult to even get the line tap to cut through the pipe without it collapsing or worse still they do not give you a charging stub long enough to fit a valve on.
Me I do it this way, I pierce the stub with piercing pliers and check the pressures. If the appliance is short of gas I vac it out and charge with scales. I then crimp up the stub and seal the hole with a blob of braze. Or if I am worried about further leaks I scrap the machine.
Finally, a number of engineers have had the misfortune of having an appliance explode after a repair – I guess its you call and your public liability insureance 8)
Re: hotpoint larder fridrge
Dangerous when folks think that there would be a mere puff if it leaked.Depends where it is the smaller enclosed space it’s in would increase the chances of a bigger bang,600/600a is a purified substance so the calorific value is higher than normal lpg .
Out of interesst I got myself a bunsen burner recently and connected it up to a scrap fridge in the workshop to see how long it would burn for,lovely clean blue flame, not long enough to boil a kettle but enough to make you realise why there are problems! certainly gives you food for thought,especially when the commercial fridges in catering etc are allowed a bigger charge than the domestic ones.
The industry does need to tighten up and standardise working methods.
That’s likely to be where a compulsory qualification comes in,does F gas qualification cover this?
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