REMKO PWW Series - Manual (Page 33)

33
Planning • Calculation • Units
We reserve the right to make changes to dimensions and design in the interest of technical advances.
Symbol Unit Explanation
Q kW Heating capacity of air heater Q = Q
H
+ Q
AL
Q
H
kW Heating requirement for room to be heated
Q
AL
kW Heat requirement to heat fresh air to room temperature Q
AL
= V
AL
· C
PL
· ∆
t
Q
L
kW
Effective heating capacity of air heater with mounted
accessory components
V m 3 /h
Air volume flow of air heater without mounted
accessory components
V
L
m 3 /h
Effective air volume flow of air heater with mounted
accessory components
V
L
= V · f
V
V
AL
m 3 /h Fresh air volume flow V
AL
= X · B · L
V
W
l/h Heating medium volume flow V
W
=
t
L1
°C Air inlet temperature at air heater
t
L2
°C Air outlet temperature at air heater
∆t °C Air inlet/outlet temperature difference at air heater ∆t = t
L2
– t
L1
∆t
W
°C Heating medium inlet/outlet temperature difference at air heater ∆t
W
= t
W1
– t
W2
∆t °C
Effective air inlet/outlet temperature difference at air heater
with mounted accessory components
∆t
L
= ∆t · f
L
C
PL
Specific heat capacity of air at constant pressure
ϕ
L
Dry air density
L m Length of room to be heated
W m Width of room to be heated
H m Height of room to be heated
X 1/h Number of air changes in room to be heated
f
Q
- Heat output factor f
Q
= Q
L
/ Q
f
V
- Air capacity ratio f
V
= V
L
/ V
f
L
- Air heating factor
∆P
W
kPa Heating medium resistance (pressure loss on water-side)
∆P
ST
Pa Static pressure difference with mounted accessory components
D - Pressure difference value with mounted accessory components
kg
m 3
860 · Q
t
W
kWs
———
kg · K
kWs
1 ———
kg · K