Methods to size hrv’s, Heating load btu – Bryant HRVBBSVC User Manual
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METHODS TO SIZE HRV’S
METHOD 1
1. Calculate cu ft of occupied space.
2. Multiply by recommended air changes per hr (AC/h).
3. Divide by 60 minutes per hr to convert to CFM.
EXAMPLE:
2000 sq ft with 8 ft ceiling
0.35 air changes per hr (AC/h)
(2000 sq ft x 8 ft ceiling x 0.35 AC/h) / 60 min/h = 93.3 CFM
METHOD 2
1. Multiply number of people times 15 CFM/person.
2. Multiply number of bath rooms 20 CFM/each.
3. Add 25 CFM for kitchen.
EXAMPLE:
2 people
2 baths
1 kitchen
(2 x 15) + (2 x 20) + 25 = 95 CFM
ADDITIONAL HEATING AND COOLING LOAD CHARTS
Although the ventilators process the outside air before it enters the home, additional heating and cooling loads need to
be considered.
HEATING LOAD BTU
The heating load chart shows the heating loads in Btuh for a range of winter design temperatures for each model of
ventilator.
EXAMPLE:
The heating design temperature for Milwaukee, WI is –4°F. At –5°F, the additional heating load of the
HRVBBLHU1250 is 8417 Btuh. This additional load should be taken into consideration when sizing the
heating equipment.
Outside
Temp °F
Heat Load (Btuh) @ Inside Design Temp 72°F
HRVBBLHU1150 HRVBBSVC1250 HRVBBSVC1150 HRVBBSVC1200
HRVBBLVU1150
HRVBBLVU1200
HRVBBLVU1330
–25
4,688
8,165
6,970
7,690
5,500
6,650
9,990
–20
4,466
7,744
6,470
7,090
5,030
6,070
9,310
–15
4,598
8,008
5,990
6,520
4,590
5,510
8,650
–10
4,334
7,547
5,520
5,970
4,160
4,970
8,000
–5
4,069
7,087
5,070
5,440
3,750
4,470
7,380
0
3,805
6,627
4,550
4,840
3,300
3,910
6,640
5
3,541
6,167
4,130
4,360
2,940
3,470
6,060
10
3,502
6,100
3,730
3,900
2,600
3,050
5,500
15
3,220
5,608
3,290
3,400
2,240
2,600
4,870
20
2,938
5,116
2,930
3,000
1,940
2,240
4,350
25
2,950
5,138
2,580
2,610
1,670
1,910
3,850
30
2,636
4,591
2,240
2,250
1,410
1,600
3,370
35
2,322
4,045
1,900
1,880
1,160
1,300
2,870
40
2,009
3,498
1,600
1,560
1,
940
1,040
2,430