Denco D28AVH

[RBK36]

Hi Chaps,
Does anyone have a pipe size chart for R407c refrigerant, coz i have a Denco unit which was commissioned back in 2008 with 25kg of refrigerant. i think this is wrong as the gauges tell me a different story. I've checked the pipe run and it is 128meters roughly from indoor to oudoor and back again. The pipe size is 1" 7/8 and 5/8" i have just reclaimed 24kg. Pressure tested and vacced and re-charged with 32kg, i bomb charged the system till i had a full sight glass and then trim charged. The problem is i am only getting 14bar discharge pressure and 3.5bar SUCTION pressure with both COMPRESSORS running. I have checked the FSC and i would of thought that with the outside temperature at -0degrees today the FSC would not be working at full speed. Can anyone help........

Cheers
RBK36

[Brian_UK]

....and what is the evaporator doing?

Any temperatures to help us?

[Grizzly]

When you say checked the fan speed controller have you tried adjusting it to raise the sys pressures slightly.
You have a huge pipe run there to influence the liquid line temps.
Particularly at this time of year.
Grizzly

[RBK36]

Hi Guys sorry been busy!!!!!
the evaporator was 11.2 degrees C, the suction pipe temp was about 7.8degrees C and the discharge pipe was 47degrees C. I switched the FSC off at the MCB and the head pressure went up and the unit tripped out. I have two other Denco units in the same data centre and the FSC were only doing 0.02Amps and 5.0Amps. If any of that helps let me know......

[RBK36]

sorry that was suppose to read 0.02amps and not 5.0Amps as the one i was working on.....

[Brian_UK]

A unit with 25kg of gas and the condenser fan is only taking 0.02 amps!?

Is the motor big enough?

[Denco Technical]

The max pipe run we allow is 100mts, at thats with a d28 (need to know the condenser) its 1 1/8 and 3/4 pipework.

At 100mts the refrigerant charge should be 36.2kgs per circuit.

I think you need to sort out you pipework first as its miles off.