PSG Caddy PF01010 Installation And Operating Instructions Manual page 20

3. Make the following verifications:
a) Oil furnace:
CFM = orifice size (SI)(liter/hour) x 39 023 x E
CFM = orifice size (Imperial)(gallon/hour) x 140 000 x E
E : Average heat generator efficiency (0.75)
t: Temperature rise (ºC)
b) Electric furnace:
1.21
Re = Electrical energy input rate, kW
t = Temperature rise (ºC)
c) Gas furnace:
1.21
Rg = Gas input rate, kW
Eg = Efficiency of a typical atmospheric gas furnace (0.7)
4. After the installation of the add-on, the original numbers must be restored in
order to maintain a constant air flow through the furnace.
1.21 x t
1.1 x t
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