Correction Of Heating Capacity For Frost And Defrosting; Method For Obtaining The Equivalent Piping Length; Correction Factor Diagram - Mitsubishi Electric PUMY-P250YBM Technical & Service Manual

Figure 13 PUMY-P300YBM
1.00
0.95
0.90
0.85
0.80
0.75
0.70
0.65
0
Figure 14 PUMY-P300YBM
1.00
0.95
0.90
0.85
0.80
0.75
0.70
0.65
0

(2) Method for Obtaining the Equivalent Piping Length

Equivalent length = (length of piping to farthest indoor unit) + (0.3 o number of bends in the piping) (m)

4-4-1. Correction of Heating Capacity for Frost and Defrosting

If heating capacity has been reduced due to frost formation or defrosting, multiply the capacity by the appropriate correction
factor from the following table to obtain the actual heating capacity.

Correction factor diagram

Outdoor Intake temperature (°C W.B.)
Correction factor
OCH760
<Cooling>
20 40 60
Piping equivalent length (m)
<Heating>
20 40 60
Piping equivalent length (m)
6 4 2
1.00 0.98 0.89
Total capacity of indoor unit
80 100 120
80 100 120
0 −2 −4
0.88 0.89 0.90 0.95
20
140 160 180
140 160 180
−6 −8 −10 −15
0.95 0.95 0.95
16.75
25.13
33.5
43.5
−20
0.95