Retrotec DucTester 341 User Manual
Page 62
Page 62 of 83
©Retrotec Inc. 2014
CFM
25
multiplier for return = 1.22
CFM
25
multiplier for supply = 1.0 (default)
Leakage splits:
SLS = 200 CFM
25
/ 270 CFM
25
= 0.74
RLS = 70 CFM
25
/ 270 CFM
25
= 0.26
Loss Factors:
SLF = (0.74 x 1.0 x 1.22) = 0.9
RLF = (0.26 x 0.5 x 1.0) = 0.13
% HVAC System Loss =
270 CFM × (0.9+0.13)
1425 CFM
= 20%
Annual cooling loss = 20% x $1300 = $260
Annual heating loss = 20% x $ 500 = $100
Annual capacity loss = 20% x 3 ton = 0.6 tons
Annual operating SEER = (1 – 20%) x 11 SEER = 8.8 SEER