Heating Systems (Hastings Industries Inc.)

"R" SERIES ROOFTOP SYSTEMS

Blower Table - RHFA, RMUA & RHVA Models with Double Bank Furnaces

Model NO. & MBH Input	Btuh Output	Ship Wt. Lbs.	Blower Used	Duct Furn. used	Air Temperature Rise
					20°			25°			30°			35°			40°			45°
					CFM	Total S.P.	HP	CFM	Total S.P.	HP	CFM	Total S.P.	HP	CFM	Total S.P.	HP	CFM	Total S.P.	HP	CFM	Total S.P.	HP
600	456,000	2,015	218	2) 300	21,120	.75 1.57	10 15	16,900	1.01 1.52	7-1/2 10	14,080	.88 1.50	5 7-1/2	12,060	1.18 1.84	5 7-1/2	10,560	.81 1.41	3 5	9,400	.97 1.59	3 5
800	608,000	2,425	218	2) 400	28,160	.53 -	20 -	22,520	.49 1.28	10 15	18,760	.69 1.18	7-1/2 10	16,100	1.14 1.67	7-1/2 10	14,080	.81 1.50	5 7-1/2	12,520	1.11 1.77	5 7-1/2

Blower Table - RHFA, RMUA & RHVA Models with Double Bank Furnaces

Model NO. & MBH Input	Btuh Output	Ship Wt. Lbs.	Blower Used	Duct Furn. used	Air Temperature Rise
					40°			50°			60°			70°			80°			90°
					CFM	Total S.P.	HP	CFM	Total S.P.	HP	CFM	Total S.P.	HP	CFM	Total S.P.	HP	CFM	Total S.P.	HP	CFM	Total S.P.	HP
1000	760,000	3,090	218	4) 250	17,600	.89 1.39	7-1/2 10	14,080	.88 1.50	5 7-1/2	11,740	.65 1.24	3 5	10,060	.87 1.48	3 5	8,800	1.05 1.68	3 5	7,820	.77 1.18	2 3
1200	912,000	3,230	218	4) 300	21,120	.75 1.57	10 15	16,900	1.01 1.52	7-1/2 10	14,080	.88 1.50	5 7-1/2	12,060	1.18 1.84	5 7-1/2	10,560	.81 1.41	3 5	9,400	.97 1.59	3 5
1600	1,216,000	3,560	218	4) 400	28,160	.53 -	20 -	22,520	.49 1.28	10 15	18,760	.69 1.18	7-1/2 10	16,100	1.14 1.67	7-1/2 10	14,080	.88 1.50	5 7-1/2	12,520	1.11 1.77	5 7-1/2

NOTES: Total static pressure shown in inches of water.

Shaded areas require cleanable filters.

Equipment Selection

RHF-SPACE HEATING

1. Select model size according to Btuh requirements.

2. Specify desired air delivery or temperature rise. For normal applications, an air delivery resulting in a 70° F temperature rise in recommended.

3. Specify motor size to deliver the selected SCFM against required TSP (total static pressure).

RMU-MAKE-UP AIR

1. Check the exhaust specifications or equipment to determine the total SCFM of fresh air required.

2. Increase the total SCFM by approximately 10% if building needs to be slightly pressurized.

3. Determine air temperature rise, usually 70° F minus winter outside design temperature.

4. Select model and motor size to deliver desired air temperature rise and SCFM against required TSP.

RHV - HEATING & VENTILATING

1. Calculate the total SCFM of outside air needed to satisfy exhaust air requirements and meet ventilation specifications.

2. Find the Btuh output needed to heat the total SCFM of outside air by multiplying SCFM X TD (room temperature minus winter outside design temperature) X 1.08.

3. Find total Btuh output by adding the space heat loss to the btuh ventilation requirement from step 2.

4. Select model and motor size to deliver total Btuh output and SCFM against required TSP. The SCFM chosen must equal or exceed the volume required for ventilation.

NOTE: Total static pressure as found in the blower tables must overcome total system resistance. Duct furnace and accessory equipment air pressure losses are found on page 6 of this bulletin. Total system resistance is the total of these pressure drops added to the air pressure loss of all system duct work and registers.

Heating Systems - Page 4