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GIRI
05-06-2013, 07:22 AM
hi all i am new to HVAC . i just want to how to find out on / off coil temperature.

for example : Outdoor temp 45 deg and 90 RH
Room temp 24 deg and 50 RH
MY AIRFLOW IS 16250 CMH
SENSIBLE LOAD 54.85 KW

moideen
05-06-2013, 09:57 AM
hi all i am new to HVAC . i just want to how to find out on / off coil temperature.

for example : Outdoor temp 45 deg and 90 RH
Room temp 24 deg and 50 RH
MY AIRFLOW IS 16250 CMH
SENSIBLE LOAD 54.85 KW
on coil of AHU/FCU= air entering temperature
off coil of AHU/FCU= air leaving temperature

GIRI
05-06-2013, 11:00 AM
on coil of AHU/FCU= air entering temperature
off coil of AHU/FCU= air leaving temperature


Thank you moideen,

I just want to know how you will finalise the on coil and off coil temperature. is there any regulation or formula..?

Rob White
05-06-2013, 11:35 AM
.

Rough rule of thumb is 10 degs difference.

Air off is lower than air on and if it is 10 degs lower then
the thing is working.

(this is a rough rule of thumb that is a guide only)

Regards

Rob

.

The Viking
05-06-2013, 03:31 PM
First you would have to determine what type of kit you are looking at.

In your example above, for the indoor coil, the on coil temp would be 24 degrees for a recirculating unit and 45 degrees for a 100% fresh air unit...
The off coil temp should then ideally be around 10 degrees below your room temp i.e. 14 degrees (assuming we are talking cooling and not heating...).

:cool:

GIRI
06-06-2013, 01:49 AM
First you would have to determine what type of kit you are looking at.

In your example above, for the indoor coil, the on coil temp would be 24 degrees for a recirculating unit and 45 degrees for a 100% fresh air unit...
The off coil temp should then ideally be around 10 degrees below your room temp i.e. 14 degrees (assuming we are talking cooling and not heating...).

:cool:



thank you all for your information

lh.ahn84
15-06-2013, 01:26 PM
Fresh AIr Ratio? Supply air flow?