gas appliances

[murdock]

i went to look into getting a gas geyser today...i was told that i had to use a approved gas installer...i dont understand why i must pay a person to come to my house screw a gas geyser onto the wall...then connect it to the bottle... i do this literally every week when i change my bottles.

what does it take for me to become the 30 001 st authourised installer in south africa?

[Justloadit]

Hi Murdock,

When it comes to gas, there is much more than meets the eye.

As a simple example, a copper pipe may not touch the wall that it is going through or going along on, as there could be some corrosion taking place causing a gas leak. Certain types of metals may not be used in the installation due to chemical reactions. There must be blow back valves installed, to ensure that oxygen never gets into the system, and others. I am not aware of all the regulations, but did do this inquiry some time ago, so I may not have all the facts right now. I do remember that there many things I thought trivial, but on deeper thought realised the danger that may be exposed.

There is a very stringent set of regulations governing this, as one mistake can cause a huge explosion.

[murdock]

sounds like i need to do my homework properly....maybe i should do what people do with the electrical installations.

i will install everything then leave it for a week then call a qualified gas installer and ask him to sign it over...he will tell me what is wrong give me a quote to do the repairs...get what is required and do the changes then call him back.

[Justloadit]

Sounds like a good working plain ;>)

[AndyD]

sounds like i need to do my homework properly....maybe i should do what people do with the electrical installations.

i will install everything then leave it for a week then call a qualified gas installer and ask him to sign it over...he will tell me what is wrong give me a quote to do the repairs...get what is required and do the changes then call him back.

Sounds like you'll be doing the job twice and paying the qualified Gas guy twice for doing nothing. What happens if he uses your own technique and issues you a failur notice with just references to the regs and no explanation?

[murdock]

i did some research and found a place where i can do a 4 day course on gas installations...lpgas.co.za...after reading up on the dangers...eeeeeish maybe just do it right first time...next step is to get a gas leak solution to check joints and couplers...cost R50...but at the end of the day better safe than sorry.

i think people take gas for granted...until something goes wrong...i have a little more respect for the stuff now that i know a little better.

[Justloadit]

Hi Murdock,

Have a friend who was burnt quite badly by a gas leak, so yes, it is not forgiving.
I also suggest you invest in a permanent gas leak detector/alarm as a precaution.

Unfortunately whilst electricity may be dangerous, a protruding wire, whilst dangerous, is more forgiving than your kitchen floor covered in gas and you have a spark.

Gas is extremely violent and explosive when there is large amounts of it. The temperature can rise instantaneously to about 800 degrees centigrade when mixed with oxygen and it gets lit.

Another simple but effective way to detect leaks, is to add soap to water and use a paint brush to paint the mixture over joints. A gas leak will cause bubbles to form .

[sparkydelux]

I find it quite amusing that Refrigerattion installers (who use a much higher PSi rating the LPG) are not allowed to install gas. Bear in mind the same principles apply, and both gases can be fatal. LPG Gas, if there is a leak, can be detected quite quick due to the smell and is evidently flammable. refrigeration gases also combusitble and very hazardous.

If both gases are installed under the same principles, then why cant a fridge guy install gas? Money making scheme?
My other trade is AC/ refrigeration and I called up LPGSA to enquire but didnt really get an answer. Infact I was more confused than when I originally called.

What I am trying to say is that if I can deal with pressures of around 200PSI on testing and using Nitrogen etc why cant I transpose the same techniques onto LPG. They use far less PSI and they rely on Jubliee clips as fastening.

I was stunned to find a guy was going to come and fit my gas connection for R800 and literally fasten 2 jubilee clips. I'd also like to charge R800 for 2 jubilee clips and a bit of spray soap to check. I'm just stunned that these guys think its so involved when its not really.

BTW, we had (at our family home) a gas installation done on the hob. the guy came out, did his thing, charged and left. It was fitted inside a cupboard next to a 'pot and pan' draw that opened and closed. Anyway, 4 weeks later of opening and closing the draw, we smell gas. The DRAW had cut a groove into the hose and was causing a leak. lucky we caught it or else I'd have no folks left. When they slept they wouldnt have even known. So, for the agro of 2 jubilee clips and relying on someone elses workmanship, I am jubious on the rate they charge and the amount of technical difficulty it involves.

Hopefully they come out with something that bypasses these installers........watch this space!!

[Justloadit]

I was not aware that the 'R' range of refrigerant gas was inflammable.
There are very few fridges using LPG as a refrigerant, precisely for the reason of inflammability.
The other point is how many litres of gas in a refrigerator, as opposed to a gas supply for a stove?

[murdock]

R800 and ita 4 day course...people dont bat an eyelid to pay...charge that to do a stove connection which includes materials worht R600 and people complain...mmmm

same as a thermographer...takes 5 days to become a level 1 thermographer...and you dont even have to do the course and you can charge anything from R3500 and up...and please dont tell me it its because of the price of the equipment...my power quality analysing equipment cost twice the price of the thermal imager....so i should be charging R7000 per call out.

and now you know why a docotr charges R1800 an hour or R18000 a day + because he studied for 5 years

[Justloadit]

Well Murdock,

Get yourself a couple of more certificates, and you can then charge for doing this other work to supplement your income.

[sparkydelux]

Well Lets put it this way. A chiller can hold between 150Kg and 250Kg of Refrigerant. A fridge, couple of KG, A split unit (pre charged about 3.5kg and then top up all depends on run etc.)

I said combustible and not inflammable.

I assume ammonia is not flammable?

Some Info from institutes around the world.

Definition: A refrigerant that may ignite or burn. This includes butane, propane, isobutane and certain other hydrocarbons. Flammable refrigerants are considered dangerous because of their risks to service personnel as well as the occupants.

Refrigerant is a flammable substance and is classified three ways: Class 1, Class 2 and Class 3. Refrigerant that is classified as Class 1 is considered to be non-flammable, while Class 2 has a low flammability classification. Class 3 is considered to be highly flammable.

How is this any different from LPG?

I now retract my original quote and ammend it to 'Combustible and Flammable'. Learn another new thing everyday.

[Dave A]

i will install everything then leave it for a week then call a qualified gas installer and ask him to sign it over...he will tell me what is wrong give me a quote to do the repairs...get what is required and do the changes then call him back.

From what I've seen flowing through my biz on the gas testing side, I recommend against that. I get the sense that it costs more to fix a badly done installation than to put it in properly in the first place.

And yes, I've been staggered at what prices run at for gas installation work compared to electrical work. I expect it's because there are surprisingly few suitably qualified gas installation guys out there prepared to work on domestic gas installations. I know it's been a real scramble for us to find the right guys.

I don't know about how refrigeration stacks up against gas ito standards or hazards, but there is a SANS code that has to be met with gas installations.

When it comes to gas leaks, you don't need to "sniff it out." There's a simple pressure test where you charge the system up to ?* and lock it off for ten minutes. If the pressure doesn't drop - no leaks.

*Can't remember off-hand, but it's not that high. When I get back to work I can check up for you if anyone's interested.

[AndyD]

When it comes to gas leaks, you don't need to "sniff it out." There's a simple pressure test where you charge the system up to ?* and lock it off for ten minutes. If the pressure doesn't drop - no leaks.

This is a standard 'drop test' and it's not an accurate test. With a large installation there could be hundreds of litres of gas in the pipework and even a small pressure drop over a few minutes could mean a very large leak.

With refrigeration a deep vacuum is pulled on the entire system and a similar test is done over time but when using a vacuum a small leak will be detectable far faster than using the pressurisation method. You can't use a vacuum with a gas installation because the pipework wall thickness is insufficient and the pipe will collapse.

Refrigeration engineers are often qualified to work with LPG if they are R600a or R290a certified. Lpg is used as a refrigerant in some domestic fridges nowadays.

[Sparks]

I am also a qualified refirigaration technician and do not know of any refrigeration system with inflammable gas in the system. Sweating on such a system will definately be your last job. The only danger of a refrigerator is shock. As for LPG, I have been using it for years and consider it safer and more economical financially and time-wise provided all the safety precautions are taken. I will never trade my gas hob for an electric one.