Roberts Gorden CRV-B-9 service manual Flow Loading, Radiant Branch Flow

Page 18

CRV-SERIES DESIGN MANUAL

SECTION 5: FLOW LOADING

The patented CRV-Series burner system allows a number of burners to be installed in-series, in the same radiant tube, resulting in a long, continuous radi- ant emitting surface to give even heat distribution within the building.

To enable the burners to be correctly located within the system, to maintain system operating vacuum and obtain design flue gas temperatures at the pump, the design layout is based on a simplified flow principle using a “flow unit.”

The flow unit is defined as the amount of fuel/air mix- ture for a heat input of 10,000 (Btu/h). This corre- sponds to a flow rate of 1.83 cfm at 65-70°F.

For the purpose of design, flow units enter the CRV- Series system in one of two ways:

Through the burner.

Through the end vent plate.

Flow units exit the system as spent products of com- bustion via the pump.

The purpose of the end vent air is to dilute the hot combustion gases at the burner, thereby promoting uniform heating of the tube while avoiding excessive heating of the combustion chamber.

For the end burner, the burner inlet flow consists of the end vent air and combustion air. For all other

burners, the burner inlet flow consists the of the total of the end vent air plus the combustion gases from all upstream burners.

The requirement for minimum burner inlet flow is met if the total flow units entering the combustion chamber meets or exceeds the minimum as shown on Page 12, Table 1.

5.1 Radiant Branch Flow

The flow in a radiant branch consists of the end vent flow units plus the flow units of combustion air from all burners. Page 13, Figure 14 shows a representation of flow units for various types of branches.

The limiting factor for maximum flow in the radiant sec- tion has been determined experimentally in terms of the maximum burner inlet flow units that can be toler- ated without degradation of combustion characteristics at the last downstream burner. If more than the maxi- mum number of burners are installed per radiant branch, the vacuum loss across the additional burners will increase appreciably.

This maximum flow in the radiant branch can be expressed for each burner firing rate by either a maxi- mum number of burners per branch or the maximum number of flow units. See Page 12, Table 1.

Table 1: CORAYVAC® Design Parameters

Burner Model

B-2

B-4

B-6

B-8

B-9*

B-10

B-12A

B-12

 

 

 

 

 

 

 

 

 

Input (Btu/h) x (1000)

20

40

60

80

90

100

110

120

 

 

 

 

 

 

 

 

 

Flow Units per Burner

2

4

6

8

9

10

12

12

 

 

 

 

 

 

 

 

 

Flow Units per End Vent

6

10

15

20

15

20

20

20

(minimum flow units entering combustion chamber)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Maximum Number of Burners per Branch

6

4

4

4

2

4

3

3

 

 

 

 

 

 

 

 

 

Maximum Number of Flow Units per Branch

18

26

39

52

33

60

56

56

 

 

 

 

 

 

 

 

 

Radiant Tube Length (average distance between burners)

 

 

 

 

 

 

 

 

Minimum (ft)

10

12.5

20

20

20

30

35

35

 

 

 

 

 

 

 

 

 

Recommended (ft)

15

20

25

30

30

40

50

50

 

 

 

 

 

 

 

 

 

Maximum (ft)

20

25

35

45

50

60

70

70

 

 

 

 

 

 

 

 

 

Minimum Distance from Burner to Downstream Elbow (ft)

5

5

10

10

10

15

15

15

 

 

 

 

 

 

 

 

 

Suggested Minimum mounting Height (ft)

8

8

8

10

10

15

15

15

 

 

 

 

 

 

 

 

 

* CRV B-9 requires first downstream tube from burner to be aluminized heat-treated.

12

Image 18
Contents Design Manual Page Roberts-Gordon LLC Page Table of Figures Page Concept Safety CRV-SERIES SystemZero Regulator Assembly Overview Two Branch System Shown Fuel Savings and Comfort Clearances to combustibles at all times for safety Standard Reflector ONE Side ReflectorUniversal SHIELD, Position Foot Deco Grille Sizing and Design Considerations Radiant Adjustment to Heat LossRadiant Height Adjustment Factor ExampleRadiant Distribution Average Coverage Selecting the BurnersRadiant Distribution Radiant Distribution Increased Coverage= mounting height Flow Loading Radiant Branch FlowBurner Flow Units Pump Capacity Tailpipe FlowPump Exhaust Length Requirements Minimum Radiant Tube Length Radiant Tube and TailpipeRadiant Tube Length Maximum Radiant Tube LengthCRV-Series Design Methods Design ParametersPump Model Series Maximum Loading Flow Units Per BranchAfter Each Burner Allowable Tailpipe Lengths Burner ModelSystem with EP-300 Series Pump Tailpipe Design MethodRule of Thumb Unshared Calculations To Calculate the Total System TailpipeDamper Couplings Possible Damper Coupling Locations Example CRV-SERIES System Layouts Example System Layout Option12 m 10 3 m 20 6 m 12 m Tailpipe 10 3 m 100 30 m Example System Layout Option 7, 8 Roberts Gordon Ultravac Control MethodsRoberts Gordon System Control Corayvac Modulating ControlsPressure Switch Analog Signal Modulating ThermostatMS/TP Wiring Spst Transformer Relay Kit P/N 90417600KNon-Pressurized AIR Supply SystemPressurized Pressurized SystemsPipe sizing Duct Design RulesBlower P/N 90707501K Performance 112 Flow Units Sample Layout for Pressurized Outside Air Systems Roberts Gordon Ultravac Design Requirements CRV-SERIES Equipment Specifications
Related manuals
Manual 72 pages 5.13 Kb

CRV-B-9 specifications

The Roberts Gordon CRV-B-9 is a state-of-the-art infrared radiant heater designed for industrial and commercial heating applications. Renowned for its efficiency and effectiveness, the CRV-B-9 represents a significant advancement in the world of space heating solutions.

One of the main features of the CRV-B-9 is its advanced infrared technology, which allows for precise heating without the necessity of warming the entire space. This targeted heating provides immediate comfort, as it directly warms objects and people rather than the air around them, making it particularly effective in large warehouses, manufacturing facilities, and retail spaces.

The heater boasts an impressive output of up to 80,000 BTUs, making it suitable for a wide range of applications. It utilizes natural gas as fuel, which contributes to its efficiency and cost-effectiveness. With a robust design and durable construction, the CRV-B-9 is built to withstand the rigors of industrial environments while ensuring a long product lifespan.

Another significant characteristic of the CRV-B-9 is its ability to integrate with advanced control systems. This includes compatibility with programmable thermostats and energy management systems, allowing for optimized temperature control and reduced energy consumption. The heater can be adjusted to suit different operational needs, making it a flexible solution for various heating scenarios.

The CRV-B-9 also features a compact design, allowing for easy installation in a variety of spaces. Its low-profile shape and modular capability enable users to arrange multiple units to achieve the desired heating coverage without compromising floor space, a crucial aspect for busy, high-traffic areas.

Safety is a priority with the CRV-B-9, which is equipped with various safety features such as a flame safety cutoff switch and over-temperature protection. These mechanisms ensure safe operation, providing peace of mind for users in demanding environments.

In summary, the Roberts Gordon CRV-B-9 infrared radiant heater stands out for its innovative technology, impressive output, energy efficiency, and safety features. Its flexibility and robust design make it an ideal choice for businesses looking to enhance comfort while minimizing energy costs. Whether in a manufacturing plant or a retail outlet, the CRV-B-9 provides a reliable and effective heating solution.