I recently acquired a brand new 1.4 pound cylinder of Genetron 245fa refrigerant. I had never heard of it before, but upon reading the label, I found that it boils at 60 deg F at atmospheric pressure - very interesting for certain thermodynamic uses. The first thing that occured to me was that it may make a good alternative fill gas for those P6015 HV probes often discussed here.

I looked it up and found that it's been around for ten years or more, and was developed as a new non-ozone-depleting refrigerant for many applications, especially solar power. It may be worth looking into for P6015s, although maybe only for indoor room temperature use - you wouldn't want to put very high voltage on it with a vacuum in there when it's cold.

Ed

Hi Ed.. very interesting indeed, what about the cost?.
Just for the record, several time I had the insane temptation to fill my probe from lighter butane..and see what..!
Gabriel.
--- In TekScopes@yahoogroups.com, "Ed Breya" <edbreya@> wrote:

I recently acquired a brand new 1.4 pound cylinder of Genetron 245fa refrigerant. I had never heard of it before, but upon reading the label, I found that it boils at 60 deg F at atmospheric pressure - very interesting for certain thermodynamic uses. The first thing that occured to me was that it may make a good alternative fill gas for those P6015 HV probes often discussed here.

I looked it up and found that it's been around for ten years or more, and was developed as a new non-ozone-depleting refrigerant for many applications, especially solar power. It may be worth looking into for P6015s, although maybe only for indoor room temperature use - you wouldn't want to put very high voltage on it with a vacuum in there when it's cold.

Ed

 

Hi Ed.. very interesting indeed, what about the cost?.
Just for the record, several time I had the insane temptation to fill my probe from lighter butane..and see what..!
Gabriel.
--- In TekScopes@..., "Ed Breya" wrote:
>
> I recently acquired a brand new 1.4 pound cylinder of Genetron 245fa refrigerant. I had never heard of it before, but upon reading the label, I found that it boils at 60 deg F at atmospheric pressure - very interesting for certain thermodynamic uses. The first thing that occured to me was that it may make a good alternative fill gas for those P6015 HV probes often discussed here.
>
> I looked it up and found that it's been around for ten years or more, and was developed as a new non-ozone-depleting refrigerant for many applications, especially solar power. It may be worth looking into for P6015s, although maybe only for indoor room temperature use - you wouldn't want to put very high voltage on it with a vacuum in there when it's cold.
>
> Ed
>

Does it boil at 60 deg F or -60 deg F at atmospheric pressure? 60 deg
doesn't sound like a great refrigerant unless perhaps used in a low
pressure system.

Don Black.

 

+59.5 F (15 C) according to MSDS.
Albert

> Does it boil at 60 deg F or -60 deg F at atmospheric pressure? 60 deg
> doesn't sound like a great refrigerant unless perhaps used in a low
> pressure system.
>
> Don Black.

Thanks, my original comments still apply. Maybe there's a refrigeration
Guru here who can shed more light on its use in refrigeration.

Don Black.

On 11-Jun-13 7:00 PM, Albert wrote:

+59.5 F (15 C) according to MSDS.
Albert

Does it boil at 60 deg F or -60 deg F at atmospheric pressure? 60 deg
doesn't sound like a great refrigerant unless perhaps used in a low
pressure system.

Don Black.

+59.5 F (15 C) according to MSDS.
Albert

Does it boil at 60 deg F or -60 deg F at atmospheric pressure? 60 deg
doesn't sound like a great refrigerant unless perhaps used in a low
pressure system.

Don Black.

--------------------------------------------------------------------------------

No virus found in this message.
Checked by AVG - www.avg.com <http://www.avg.com>
Version: 10.0.1432 / Virus Database: 3199/5900 - Release Date: 06/10/13

In the search for dielectric fluids for the P6015 this article "Dielectric properties of alternative refrigerants" might be very interesting. HFC-245fa is one of the discussed refrigerants. Someone having access to IEEE publications?

http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=1657961&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D1657961

Albert

Systems don't need to be low pressure. Electronics are moving to higher
temperature operation (cooling is a major cost of data centers) and the higher
temperature refrigerants are used in phase change heat pipe systems as well as
pumped (not compressed) refrigerant loops. That's what my company had been
experimenting with using HFE-7000.


On 6/11/2013 5:00 AM, Albert wrote:

+59.5 F (15 C) according to MSDS.
Albert

Does it boil at 60 deg F or -60 deg F at atmospheric pressure? 60 deg
doesn't sound like a great refrigerant unless perhaps used in a low
pressure system.

Don Black.

--------------------------------------------------------------------------------

No virus found in this message.
Checked by AVG - www.avg.com<http://www.avg.com>
Version: 10.0.1432 / Virus Database: 3199/5900 - Release Date: 06/10/13

------------------------------------

Yahoo! Groups Links

Thanks, my original comments still apply. Maybe there's a refrigeration
Guru here who can shed more light on its use in refrigeration.

Don Black.

On 11-Jun-13 7:00 PM, Albert wrote:

+59.5 F (15 C) according to MSDS.
Albert

Does it boil at 60 deg F or -60 deg F at atmospheric pressure? 60 deg
doesn't sound like a great refrigerant unless perhaps used in a low
pressure system.

Don Black.

 

If it boiled at -60, it wouldn't have been "interesting," and I wouldn't have mentioned it in the first place, and we wouldn't be talking about it. Boiling near room temperature allows for a whole new set of applications, since refrigeration (or really heat transport) depends on changing between gas and liquid phases at suitable temperatures and pressures.

The P vs T and enthalpy charts show how the different refrigerants work and why there are different ones for various applications.

The higher boiling point means lower pressure near room temperature, so using it in a P6015, for example, means that the pressure won't get very high at normal temperature - otherwise it could blow a gasket or burst the container - the probe housing in this case. The chart shows that at a maximum ambient of say 120 deg F, P will be 34 PSIG. A more conventional refrigerant like R134a would be around 100 PSIG or so.

The downside is that R-245fa will actually create a relative vacuum below its boiling point of 60 deg F - it still must exist at a positive absolute pressure at low density, but it will be a negative gauge pressure, with respect to atmosphere, so the seals of the container may not work the same and possibly leak. The lower density as it approaches true vacuum (at around 30 deg F) also means that it won't serve its purpose as a dielectric anymore - there won't be enough of its gaseous form.

Ed

--- In TekScopes@..., Don Black wrote:
>
> Thanks, my original comments still apply. Maybe there's a refrigeration
> Guru here who can shed more light on its use in refrigeration.
>
> Don Black.
>
> On 11-Jun-13 7:00 PM, Albert wrote:
> >
> > +59.5 F (15 C) according to MSDS.
> > Albert
> >
> > > Does it boil at 60 deg F or -60 deg F at atmospheric pressure? 60 deg
> > > doesn't sound like a great refrigerant unless perhaps used in a low
> > > pressure system.
> > >
> > > Don Black.
> >
> >
>

Fair enough Ed, I thought it was first mentioned as a refrigerant (to
make cold) not as a freon replacement in probes.

Don Black.

On 11-Jun-13 11:45 PM, Ed Breya wrote:

If it boiled at -60, it wouldn't have been "interesting," and I
wouldn't have mentioned it in the first place, and we wouldn't be
talking about it. Boiling near room temperature allows for a whole new
set of applications, since refrigeration (or really heat transport)
depends on changing between gas and liquid phases at suitable
temperatures and pressures.

The P vs T and enthalpy charts show how the different refrigerants
work and why there are different ones for various applications.

The higher boiling point means lower pressure near room temperature,
so using it in a P6015, for example, means that the pressure won't get
very high at normal temperature - otherwise it could blow a gasket or
burst the container - the probe housing in this case. The chart shows
that at a maximum ambient of say 120 deg F, P will be 34 PSIG. A more
conventional refrigerant like R134a would be around 100 PSIG or so.

The downside is that R-245fa will actually create a relative vacuum
below its boiling point of 60 deg F - it still must exist at a
positive absolute pressure at low density, but it will be a negative
gauge pressure, with respect to atmosphere, so the seals of the
container may not work the same and possibly leak. The lower density
as it approaches true vacuum (at around 30 deg F) also means that it
won't serve its purpose as a dielectric anymore - there won't be
enough of its gaseous form.

Ed

--- In TekScopes@yahoogroups.com <mailto:TekScopes%40yahoogroups.com>,
Don Black <donald_black@> wrote:

Thanks, my original comments still apply. Maybe there's a refrigeration
Guru here who can shed more light on its use in refrigeration.

Don Black.

On 11-Jun-13 7:00 PM, Albert wrote:

+59.5 F (15 C) according to MSDS.
Albert

Does it boil at 60 deg F or -60 deg F at atmospheric pressure?

60 deg

doesn't sound like a great refrigerant unless perhaps used in a low
pressure system.

Don Black.