AHU'S COIL PRESSURE DROP
AHU'S COIL PRESSURE DROP
(OP)
hi every body,
ahu with the following previous data at 46 c outdoor:
chilled water in : 7.0 c
out: 12.0 c
pressure drop : 7 psi
booster pump
indoor 22-23 c
NOW after adding :
1 3-way globevalve
1 balancing valve
stop booster pump
increasing the water flow rate (may be 1.5)
we have :
chilled water in : 7.0 c
out: 9.5 c
pressure drop : 15 psi
but!!!!! indoor 25-26 c (at the same load)
why?
is it true :
1. increasing flow however will reduce supply air temp.
2. lower in-out means lower air temp.
ahu with the following previous data at 46 c outdoor:
chilled water in : 7.0 c
out: 12.0 c
pressure drop : 7 psi
booster pump
indoor 22-23 c
NOW after adding :
1 3-way globevalve
1 balancing valve
stop booster pump
increasing the water flow rate (may be 1.5)
we have :
chilled water in : 7.0 c
out: 9.5 c
pressure drop : 15 psi
but!!!!! indoor 25-26 c (at the same load)
why?
is it true :
1. increasing flow however will reduce supply air temp.
2. lower in-out means lower air temp.





RE: AHU'S COIL PRESSURE DROP
BTUH = GPM x (Tin-Tout)x 500 you can see if you increase the gpm the btuh will increase...BUT that assumes that delta "T" remains constant; in your case it goes down like said because of the reason above.
RE: AHU'S COIL PRESSURE DROP
really,it is not clear to me that increasing flow will increase air temp!
RE: AHU'S COIL PRESSURE DROP
RE: AHU'S COIL PRESSURE DROP
Actually increased flow increases turbulence and so overall heat transfer coefficient.
In my opinion your flow rates might have reduced.
RE: AHU'S COIL PRESSURE DROP
RE: AHU'S COIL PRESSURE DROP
RE: AHU'S COIL PRESSURE DROP
Regards,
RE: AHU'S COIL PRESSURE DROP
note: we have 12-15 psi water pressure drop, is it normal?
RE: AHU'S COIL PRESSURE DROP
sorry bout that!
RE: AHU'S COIL PRESSURE DROP
RE: AHU'S COIL PRESSURE DROP
RE: AHU'S COIL PRESSURE DROP
RE: AHU'S COIL PRESSURE DROP
RE: AHU'S COIL PRESSURE DROP
Regards,