Bryant HRVBBSVC, HRVBBLHU, HRVBBLVU manual Methods To Size Hrv’S, Heating Load Btu, EXAMPLE 2 people

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

2baths

1kitchen

(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

Outside			Heat Load (Btuh) @ Inside Design Temp 72°F
Temp °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	940	1,040	2,430

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.

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