Metric superheat??

[McFridgeGuy]

I don't know if I'm just having a total brain fart after a long hot day, but someone riddle me this...

A Bitzer compressor, the literature states "Min. suction gas superheat 20 K".

Obviously I'm just accustomed to dF for superheat. But are they just using K for a delta (I'm aware of the actual delta symbol). The literature is all metric, so an example would be an SST of -30dC and a line temp of -10dC = 20k superheat.

Imperial converted for those numbers..
-22dF SST - (14dF) = 36dF superheat

So what would be my minimum?

[jpsmith1cm]

It seems that "across the pond" the "K" designation is used to express a temperature difference, which would be appropriate for a superheat or Delta T type situation.

The issue would arise in that 20 K superheat would be 20 Celsius degrees.

1 degree C is 1.8 degrees F.

Normally, one cannot convert directly like this meaning that, say, 10 degrees C superheat doesn't automatically convert to 18 degrees F superheat.

In this case, however, I think that you can properly convert the differential of 20 K to approximately 36 degrees superheat, which is about what you've arrived at.

[hvacrmedic]

K is degrees Kelvin. For deltaT's K and C are interchangable but K is more widely used for temperature intervals.

[McFridgeGuy]

It seems that "across the pond" the "K" designation is used to express a temperature difference, which would be appropriate for a superheat or Delta T type situation.

The issue would arise in that 20 K superheat would be 20 Celsius degrees.

1 degree C is 1.8 degrees F.

Normally, one cannot convert directly like this meaning that, say, 10 degrees C superheat doesn't automatically convert to 18 degrees F superheat.

In this case, however, I think that you can properly convert the differential of 20 K to approximately 36 degrees superheat, which is about what you've arrived at.

Perfect, thanks!

[McFridgeGuy]

K is degrees Kelvin. For deltaT's K and C are interchangable but K is more widely used for temperature intervals.

I know of kelvin and rankin, in this case kelvin converted wouldn't make any sense at all.

[hvacrmedic]

I know of kelvin and rankin, in this case kelvin converted wouldn't make any sense at all.

What? Here, enlighten yourself. http://en.wikipedia.org/wiki/Kelvin