Libert Hiross HPM

[rinsoproud]

Hello everyone,

I'm studying new model of Hiross HPM for 1 month but I understand its control not too much (iCOM controller).

We installed Hiross HPM with iCOM control to manage the dual cooling system (chilled water lead and compressor lag). Setpoint is 22 degC (+/-1 degC)and 50%RH (+/-10%RH).

Problem
The chilled water inlet is about 8 degC. Dehumidification system can control the humidity setpoint at 50%RH. However, the inlet changes to 12 degC, the humidity goes up to 70%RH - 80%RH and the compressors cannot start to dehumidify.

Question
Can I set any parameters in iCOM to control dehumidification by starting the compressors to help chilled water when the humidity is over the setpoint?

Thanks,

[goshen]

hi the answer is yes !
you change the stage sp
and the diffrential fo second stage to kick in,it is all in the manual ,
so as said many times rtfm
good luck

[Brian_UK]

Is your chilled water pipework circuit design correct, does it include a buffer tank?

Is there a steady load on the chiller or is the water temperature changing too quickly?

[rinsoproud]

Re: Brian

Yes. The circuit is correct as design. Yes. We have a buffer tank.
The water source from chiller changes from day time to another (small capacity) chiller at night time. So the water inlet rise from 8C to 12C.

Re: goshen

Could you tell me more clearly about 1st and 2nd stage setpoint?

Thanks a lot,

[DavidJ]

Check line S419 - dehumidification enabled - Yes.
Check line S130 - minimum CW temperature

[Gary]

Hello everyone,

I'm studying new model of Hiross HPM for 1 month but I understand its control not too much (iCOM controller).

We installed Hiross HPM with iCOM control to manage the dual cooling system (chilled water lead and compressor lag). Setpoint is 22 degC (+/-1 degC)and 50%RH (+/-10%RH).

Problem
The chilled water inlet is about 8 degC. Dehumidification system can control the humidity setpoint at 50%RH. However, the inlet changes to 12 degC, the humidity goes up to 70%RH - 80%RH and the compressors cannot start to dehumidify.

Question
Can I set any parameters in iCOM to control dehumidification by starting the compressors to help chilled water when the humidity is over the setpoint?

Thanks,

In order to dehumidify to 50%RH, the temp of the air as it leaves the coil must be 11K below the room temp. If the room temp is 22C, then the air off temp (measured close to the coil) must be 22-11=11C.

If the water temp is 12C, it cannot possibly drop the air temp to 11C as it passes through the coil, therefore the humidity will be higher than 50%RH.

[rinsoproud]

Thanks a lot, Gray!
I will try to explain to my customer...