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Reffnut
20-01-2010, 09:25 PM
This I my first post of many I assume.

I have a question.....

I thought that pressure of a refrigerant was directly linked to the temperature of the refrigerant, however today I had a daikin split unit on heating and on both sides I had a pressure of 15 bar with no difference at all on either gauge, however I had 60 degrees going to the evaporater and 25 coming back.

Any suggestions???
marc5180
20-01-2010, 09:46 PM
Your gauges would have been measuring the "liquid" and "discharge" pipes which explains why the pressures are the same.

You must have had 60DegC on the discharge going into the Condensor ( which on cooling is the the evap) and 25DegC coming out on the liquid line going to the expansion device.
taz24
20-01-2010, 09:47 PM
This I my first post of many I assume.

I have a question.....

I thought that pressure of a refrigerant was directly linked to the temperature of the refrigerant, however today I had a daikin split unit on heating and on both sides I had a pressure of 15 bar with no difference at all on either gauge, however I had 60 degrees going to the evaporater and 25 coming back.

Any suggestions???

I do not instantly know the answer to your question because there are so many variables.

Firstly the pressure temp relationship refers to the saturated temp of the refrigerant.

What refrigerant are you refering to?

Are you sure that the suction gauge is accurate at 15 bar?

Have you measured the superheat of the refrigerant at differant points in the system?

You need to be a bit more specific. Are the temps from the controler or are you measuring them?

taz.

.
coolstuf
20-01-2010, 09:54 PM
Spot on Marc:D
Reffnut
20-01-2010, 10:20 PM
Cheers for your quick replies and ur help

The gas is 410a and I measured the temps with a touch probe
I havnt taken any superheats yet so no info there

as u can probly tell I'm new to service as I'm an installer trying to learn the technical side
taz24
20-01-2010, 10:28 PM
Cheers for your quick replies and ur help

The gas is 410a and I measured the temps with a touch probe
I havnt taken any superheats yet so no info there

as u can probly tell I'm new to service as I'm an installer trying to learn the technical side


Nothing wrong in wanting to know more :D.

I think Marc has answered your question beter than I could.

cheers taz.

.