Daz man
18-05-2010, 06:33 PM
Folks, I am commissioning a fairly new Airedale condensing unit which feeds a dx coil in an AHU.
Whilst commissioning this morning I was having problems with low back pressures.
I was getting correct head pressures approx 250/270psi but
the back pressure kept fluctuating.
I know I have approx the correct charge of R407c as I have weighed it in myself - according to manufactures instructions.
I have checked the sensing bulb location of the External equalising expansion valve to find correct.
I was thinking of changing the Expansion valve and liquid line drier for new replacements? Also could I still be a couple of hundred grams short of refrigerant?
Any Ideas?? Many Thanks in advance.
Whilst commissioning this morning I was having problems with low back pressures.
I was getting correct head pressures approx 250/270psi but
the back pressure kept fluctuating.
I know I have approx the correct charge of R407c as I have weighed it in myself - according to manufactures instructions.
I have checked the sensing bulb location of the External equalising expansion valve to find correct.
I was thinking of changing the Expansion valve and liquid line drier for new replacements? Also could I still be a couple of hundred grams short of refrigerant?
Any Ideas?? Many Thanks in advance.