R22 vs R407C.....................again!!

[Abe]

I installed 2 LG Wall mounts, one a 5kw heat pump and one a 7Kw Wall mount, both at the same place, well sort of.

The 5kw runs on R22 and the 7Kw runs on R407C

The 5 Kw has a pipe run of 5 Metres, the 7Kw has a run of 10 Metres.

The air off temp of the R22 unit reads 5.6 Celcius. The R407C system reads 11 to 12.6 Celcius.

I had my suspicions about 407C being a dastardly gas, are my fears confirmed??

More sinister, once again we the guys at the deep end are being bullied, steam rollered into accepting what is being thrown at us by the manufacturers.

Do we have a say, or a voice. Do the manufacturers, law and legislatures, scientests care about our industry ?

Tell me that R407C is a SUPERIOR gas, and I will back down. Im not an expert or academic with a Masters degree in Chemistry or the ability to measure this darn hole in the sky.

But, I can measure the air off temperature on an air conditioner with my digital probe. And thats enough for me.

Maybe, perhaps I doth protest too much

[Prof Sporlan]

Aiyub, keep in mind that R-407C is 52 percent "dastardly evil" R134a by weight

[Gary]

The air off temp, by itself, doesn't really tell you much. It can be reduced by simply reducing the airflow.

Possibly we could say that for the same CFM per ton, given the same air on temp and humidity, the comparison would be valid, but then we would also need the same SCT, as well as the same subcooling and superheat.

[frank]

Ayb

We just had a call to a split cassette system on R407c which we installed about 2 years ago. Seems like some kids got over the fence and kicked the living daylights out of the condensing unit and the pipework. the system lost it's charge and was left open to atmosphere for a few days. When we got there the fridge line smelt awful - have you ever smelt 407 when the oil has absorbed moisture? - disgusting!!

Anyway, told the customer that the system was contaminated and would require a complete new installation - he went balistic! reckoned he would have to make a claim on the insurance. Spoke to the manufacturer and he said that R407 units were not now being manufactured at this size and so we had to fit a R410a system instead. Apparantley, all Daikin units now up to 6kw are on R410a so it appears that 407 was just a short term solution to R22. Not good news for the customer as any future problems where a replacement condensing unit is required will require a whole system replacement as spares are not being manufactured.

Frank

[Abe]

Frank,

407C is a " short term" replacement as I have reminded the forum before. New PED ( Pressure Equipment Directives) requires manufacturers to fit extra pressure relief components into their products for safety. They bypass the new regulation by passing off products with 407C which does not require this. Eventually the manufacturers will organise their assembly lines and come into line, also increase their prices to match.

So 407 will be a dodo in time to come, 410 will be flavour of the years to come, until a time comes when some shock haired and wiry scientests suddenly comes up with a notion that 410 A is causing impotency in the hedgehog population, the gas manufacturers will rub their hands with glee, Ahhh, time to make some more lovely dolly, and we go through it all over again !!

So, tell your customer Frank, Tough...........You will have new stuff, or you sweat................Dont blame me, Im only the fitter

[angryk]

Damn straight