Oil compatability!

[daddymac]

Hi Guys,

I'm replacing an R407c LG system with a R410 Mitzi system. I'd like to re use the existing pipework as it's the correct size. The only issue I see is oil compatibility.
The LG was replaced as it er, fell apart! Compresor was ok, so no acid etc!
Does anyone see a problem with using the old pipes?

DM

[frank]

As both R407C and R410A use POE oil I don't see any problems. Might be an idea though to flush the pipework to remove any swarf that may be in there.

[Andy]

Hi Guys

just a thought, what about the pipe wall thickness, will the pipe be able to safely handle the extra pressure.

Kind Regards. Andy

[NoNickName]

Hi Guys

just a thought, what about the pipe wall thickness, will the pipe be able to safely handle the extra pressure.

Kind Regards. Andy

Good advice. The service pressure is increased accordingly and shall be certified for 40bar.
The Schrader valves are different too.

[frank]

We are currently installing R410A systems like everyone else is these days and using new copper tubing from different suppliers.
We've asked these suppliers if the copper tube is thicker wall suitable for R410A but they all say - no it's just the same tube we've been selling for years. They don't intend to stock 2 types of tube.

Do you know anyone who sells thicker walled tube specifically for R410A.

This Mitsi guide to R410A passes the onus back to the supplier as well http://www.bdt.co.nz/comfortmaster/d...410a_guide.pdf

[Andy]

Hi Frank

The Dean and Wood Catalogue has a section just before the pipe that gives the swg needed, the small sizes are usually the same, but 3/4" and above are different I think

Kind Regards. Andy

[Slim R410a]

Had a letter a while back from HRP saying that there copper (kme) is fine for R410a working pressures and they will not be stocking different wall thicknessess.

I might have to do a similar job soon too, replacing a R407c Vent Axia system with a Fujitsu R410a, spoke to Fujitsu tech they said the old oil will be ok.

If your using Mitsi power inverters then wouldnt worry at all as they have an activated charcaol filter designed for using existing pipework. I've done this a few times using old R22 pipework with no trouble at all just make sure its good for 33Bar!

[Peter_1]

Till 5/8,you can use the same pipes and still meet PED requirements.
Has someone ever tried to burst a pipe?? I did many years ago when I worked for a big contratcor and we had a lot of spare time !
3/8 was over 100 bars and 1/2 was just below 100 bars.

Ever pressurised a PET botlle like Cola? no?? I did! Went till 12 bar!!

Don't try this at home kids!!

[NoNickName]

Diameter and thickness are different things.
E.g. 22mm (7/8 for SI units impaired ones ) is available in 1 and 1.5mm thickness (probably others).
22x1 is suitable for PS 29 bar, but it is not for PS 40 bar. And this has nothing to do with bursting capabilities, but more with safety coefficients.
Anyway, preinsulated pipes with refrigerants suitability marks as avalable on the market. I wouldn't be ready to use existing piping, which history is unknown to me, maybe bought by a plumber from a general hardware store.
One moron of an installer (I happen to know) used tap water copper piping for a DX CCU.
We refused to start it up until all the piping was replaced with refrigeration grade copper.

[Peter_1]

I knew this but the copper we buy here is Wieland or the Refrigeration copper normally delivered on a coil of 50 ft or 100 ft.
We can't buy those in different thickness.

We also don't select the copper on price but on quality you know.

Coils 'in Italy' are made many times in 0.3 mm thickness in 3/8 and pressurised according PED.
If I spit on it, I have a knock in it.

[NoNickName]

Coils 'in Italy' are made many times in 0.3 mm thickness in 3/8 and pressurised according PED.
If I spit on it, I have a knock in it.

There is no copper producer in Italy.
We buy from finnish Outokumpu.
22mm wide pipe is not coiled, but you already knew.

[phil68]

Till 5/8,you can use the same pipes and still meet PED requirements.
Has someone ever tried to burst a pipe?? I did many years ago when I worked for a big contratcor and we had a lot of spare time !
3/8 was over 100 bars and 1/2 was just below 100 bars.

Ever pressurised a PET botlle like Cola? no?? I did! Went till 12 bar!!

Don't try this at home kids!!

Yep, but not intentionally. An HP switch on the 2nd stage of a cascade system didn't do it's job about 15 years ago on a test chamber I was working on -& there was no pressure relief valve . I had tinnitus for a week

[Temprite]

Heard once of tube rupturing in an existing system.

Contractor had used cheap tubing which apparently had a seam along its length.

Does anyone here use the 20m lengths of pre insulated tube for splits up to 3/4" comes with liquid and gas pipe in one roll. The better quality is by KEMBLA.
It is also 410A rated although there is some cheap stuff that is only rated for R22.

[Slim R410a]

On the subject of this I'm looking at replacing 2No. R407c 7.1kw Toshiba with Hitachi R410a Utopia. Has anyone done any R407c replacement like this, should it be a problem?

Would normally use a Mitsi power inverter with replace filter but going for Hitachi as they do a 11.2kw wall (10.6 UK, 7.5kw sensible) so will be getting an extra 3kw in the room for the same price. Server Room.

[R1976]

In the UK for R410A:-

Use soft drawn pipe on coils up to 5/8".

Above this use hard drawn to 1"1/8.

These are rated above the safety cut out of the manufacturers equipment.

Above 1"1/8 you need to look at your suppliers pressure/temperature chart and maybe use 16 gauge copper.

I don't know anyone who uses pre insulated pipes in the UK. They cannot be bent very tight by hand and look s**t when installed!