Burnham BH Selection Procedure HOT Water Application, Water Flow Rate, 125,020 Btu/hr Final Air

G.SELECTION PROCEDURE - HOT WATER APPLICATION

Example 1:

GIVEN DESIGN CONDITIONS:

Unit Heater Model: BV-59, Entering Water Temperature: 250°F, Entering Air Temperature: 70°F

APPLICATION PROCEDURE:

1.	Capacity:	BtuA= BtuS x Heating Capacity Factor	￿	The standard capacity of an BV-59 is
		=44,300 x 1.272 = 56,350 Btu/hr		44,300 Btu/hr from Table 9.
			￿	Steam heating capacity conversion factor
				for given circumstance is1.272 from Table 11.
2. Water Flow Rate:		Same as standard	￿	The standard capacity on BV-59 is based upon a
				water flow rateof 4.5 GPM, from Table 9.
3.	Final Air	FATA = EATA + [(460 + EATA) /	￿	The standard airflow of an BV-59 is 1150 CFM,
	Temperature:	(576 x CfmS) / BtuA -1)]		from Table 9.
		FATA = 70°F + [(460 + 70) /
		(576 x 1150) / 56,350-1)] = 119°F
4. Max. Mounting		WTDA = BtuA / (480 x GA) = 56,350 /	￿	The standard capacity on BV-59 is based upon a
	Height:	(480 x 4.5) = 26.09°F		water flow rate of 4.5 GPM, from Table 9.
			￿	The max. mounting height at standard condition
5. Max. Mounting		MMHA = MMHS x Correction Factor		is 14 feet, from Table 9.
	Height:	= 14 feet x 0.86 = 12.0 feet	￿	The mounting height correction factor is
				0.86 from Table 14.

Example 2:

GIVEN DESIGN CONDITIONS:

Horizontal Air Delivery requested, Heating Load: 120,000 Btu/hr, Entering Air Temp.: 50°F, Entering Water Temp.: 180°F

APPLICATION PROCEDURE:

1.	Unit Selection:	BtuS= BtuA x Heating Capacity Factor	￿	Hot Water heating capacity conversion factor for
		=120,000 / 0.940 = 127,660 Btu/hr		given circumstance is 0.940 from Table 11.
		(at standard conditions). Select BH-165.
2.	Actual Heating	The capacity of an BH-165 at actual	￿	Hot Water heating capacity conversion factor for
	Capacity:	conditions will be BtuA = BtuX x Heating		given circumstance is 0.940 from Table 11.
		Capacity Factor = 133,000 x 0.940 =
		125,020 Btu/hr
3.	Final Air	FATA = EATA + [(460 + EATA) x (BtuA)/	￿	Cfm for given circumstance is 2500 from
	Temperature:	(576 x CfmS)] = 50 x [(460 + 50 x		Table 9.
		(125,020) / (576 x 2500)] = 94°F
4. Water Temperature		WTDA = BtuA / (480 x GPMA)	￿	GPMA for given circumstance is 13.3 from
	Drop:	= 125,020 / (480 x 13.3) = 19.5°F		Table 9.
5.	Max. Mounting	MMHA = MMHS x Correction Factor	￿	The mounting height correction factor is 1.08
	Height:	= 18 x 1.08 = 19.4 feet		from Table 14.

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