Bradford-White Corp BJVS, BJVT Flow Requirements, Damage from improper flow is not warranted

Page 15

Brute Mini Hydronic Boiler

Page 15

 

 

 

 

To

 

 

System

From

 

 

System

Balancing

 

Valve

 

 

 

Balancing Valve

 

 

or optional

 

 

thermostatic union,

 

 

P/N 2400-030.

 

 

(Primary/Secondary

 

 

only)

In

 

Out

(Return)

(Supply)

 

 

Drip

 

 

Leg

Left Side View

A full size by-pass must be installed.

Figure 7. By-pass Piping.

5.3 Flow Requirements

All high recovery, low volume water boilers must have adequate flow for efficient operation. Pump selection is critical to this goal, and pumps should be selected to provide for system design water temperature rise. Table 6 details temperature rise and water flow (GPM) for the Brute Mini boilers.

Damage from improper flow is not warranted.

Failure to insure proper water flow through the heat exchanger of the boiler will void the warranty. Flow can be verified by measuring the difference in water temperatures between the boiler inlet and outlet. For example: For a BJV-100 installation, the inlet

water temperature is 160°F (71°C), and the outlet temperature is 180°F (82°C) at Normal Input Rate from the rating plate. That means there is a 20° (11°C) temperature rise through the boiler. According to Table 1, that would indicate a flow rate of 8 GPM (0.5L/S). Temperature rise must be measured with the longest (highest head) zone calling for heat alone.

Other factors to be considered before selecting a pump are pipe size, the number of fittings throughout the system, smoothness of the interior surface of the pipe, the quantity of water flowing through the pipe, whether a glycol solution is being used, and the total length of piping in the system. Table 7 provides examle pump selection criteria using Type L copper piping, one zone valve and up to eight elbows for single zone systems. Consult the factory or a qualified system designer if you have more fittings, different size or type of pipe (especially in retrofit situations), or some other unique system configuraiton not illustrated in this manual.

 

1/2" Pipe

3/4" Pipe

 

1" Pipe

 

1-1/4" Pipe

 

 

 

 

 

 

 

 

 

 

 

Size

Pump

 

Pump

 

 

Pump

 

 

Pump

 

 

H.P.

 

H.P.

 

 

H.P.

 

 

H.P.

 

 

1/25

1/12

1/25 1/12

1/6

1/25

1/12

1/6

1/25 1/12

1/6

 

 

 

 

 

 

 

 

 

 

 

50

50

99

390 680

*

*

*

*

*

*

*

75

*

35

160

300

460

640

*

*

*

*

*

100

*

*

77

150

260

330

620

*

*

*

*

125

*

*

27

80

140

170

360

600

*

*

*

160

*

*

*

25

72

57

160

330

190

480

*

225

*

*

*

*

*

*

*

110

*

69

330

*A circulator and/or primary/secondary piping are required. Consult factory.

1. Chart is based on 30°F (17°C) maximum temperature rise.

2. Calculations are based on Type L copper tubing with one zone valve and eight elbows.

3. Typical circulating pumps: 1/25 HP=Taco 007, B&G LR-20 or SLC-25, Grundfos UP15-42F, or equivalent. 1/12 HP=B&G LR- 12, Grundfos UP26-42F, or equivalent. 1/6 HP=B&G series HV, Grundfos UP43-75, or equivalent.

Table 7. Maximum Suggested Circuit Length in Feet.

 

 

 

15°F

8°C

 

 

20°F

11°C

 

 

25°F

14°C

 

Size

 

Flow Rate

Headloss

Flow Rate

Headloss

Flow Rate

Headloss

 

 

gpm

l/s

ft

m

gpm

l/s

ft

m

gpm

l/s

ft

m

50

 

5.3

0.3

0.3

0.1

4

0.3

0.2

0.1

3.2

0.2

0.1

0

75

 

8

0.5

0.6

0.2

6

0.4

0.3

0.1

4.8

0.3

0.2

0.1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

100

 

10.7

0.7

1.3

0.4

8

0.5

0.7

0.2

6.4

0.4

0.5

0.2

125

 

13.3

0.8

2.2

0.7

10

0.6

1.3

0.4

8

0.5

0.8

0.2

160

 

17

1.1

2.5

0.8

12.8

0.8

1.8

0.5

10.2

0.6

1.2

0.4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

225

 

24

1.5

5

1.5

18

1.1

3.1

0.9

14.4

0.9

1.9

0.6

 

 

 

 

gpm = Water Flow in gallons per minute. l/s = Water flow in liters per second.

 

 

 

ft = Pressure drop (headloss) through the boiler in feet of water.

m = Pressure drop (headloss) through the boiler in meters of water.

 

 

 

 

Notes: 1. Shaded area is the recommended flow and temperature rise.

 

 

 

 

2. Temperature rise and associated flow rates are based on high fire operation at the Normal Input Rate from the rating plate.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 6. Temperature Rise °F °C.

Image 15
Contents Brute Mini Table of Contents General Information General Specifications Installation InstructionsSpecifications Diagnostic ToolsBjvt models, the damper plate hole should never be blocked Field AssemblyFlooring ClearancesVenting Combustion Air SupplyExhaust Venting Vent Pipe Sizing and General Installation Common Venting SystemsVenting Multiple Appliances Inspection of Commonly Vented Appliances Gas Supply and Piping Gas ConnectionsTypical design for a sediment trap/drip leg Special Precautions for LP GasAlternate Auto-Bypass Operation Adjusting the bypassWater Connections Water PipingTypical Plumbing Installations Multi-Zone Damage from improper flow is not warranted Flow RequirementsOxygen Permeable Systems Main PowerElectrical Chilled Water SystemsWiring Diagram, Spark Ignition System Bjvs 50 Wiring Diagram, Standing Pilot System Bjvt Wiring Diagram, Spark Ignition, Two-Stage Bjvs Multiple Zone Wiring Normal Operation Operating InstructionsGrounding Auxiliary DevicesStart-up Filling the SystemBoiler Start-up Lighting the Boiler Lighting and Shutdown ProceduresHigh Altitude Burner Air Shutter Adjustment Shutdown Main Burner Shutdown Bjvt onlyComplete Shutdown General Maintenance MaintenanceBoiler Components and Their Operation General Boiler Troubleshooting TroubleshootingSymptom Cause Remedy Troubleshooting GuideStart Troubleshooting Honeywell S8600 Intermittent Pilot SystemElectrical Troubleshooting GlossaryGlossary of Terms Replacement Parts Parts ListOrdering Information BJVS-50 BJVT-50 BJVS-75 BJVT-75 Jacket and Fire Box Components Parts Identification 11.3Exploded ViewBrute Mini Hydronic Boiler H2343000