Grease Master Application Engineering Guide
Grease Master Application Engineering Guide
Grease Master Application Engineering Guide
505 Cuthbertson Street, Monroe, North Carolina 28110 Telephone (704) 289-4663 Fax (704) 289-4662 Email Address info@greasemaster.com Website www.greasemaster.com
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SECTION 2 CONTENTS
APPLICATIONS AND ENGINEERING GUIDE
Applications and Hood Selection Guide Page
Purpose -Kitchen Ventilation.2-3 Basic Requirements for Hood and Fan Selection
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III
Design Criteria...2-5 A. Hood Size B. Air Quantity Selection...2-5 Determining Exhaust Air Requirements Determining Supply Air Requirements CFM Chart....2-6 C. Static Pressure Calculations .....2-7 Hood Static Pressure Duct Static Pressure
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Other Technical Considerations ....2-8 A. Duct Collar Sizing B. Codes.....2-9 C. Standards and Options 2-10
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In order for the hood and fans to work properly, it is necessary to select the proper hood style, model, and size, as well as to correctly choose exhaust/supply fans. This section provides a guide for the proper selection of both hoods and fans.
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BACK SHELF HOOD -EXHAUST ONLY This model is similar in application to the supply and exhaust Back Shelf hood, except no supply air is provided. This unit uses all tempered air from the room. While initial investment cost is lower than make up air style, operating costs are higher due to the loss of tempered room air. Refer to Section 6. CONDENSATE HOOD Designed to function as an exhaust only hood, this style removes steam, odor, and non grease-laden air. No filters are required and generally lights are not needed. Refer to Section 7.
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Occasionally equipment is grouped conveniently in one category or another. However, more often than not, a mixture is combined under one hood. Under these conditions it is best to define the load toward the medium or heavy side (depending on the equipment) to assure that sufficient exhaust air is provided for. DETERMINING EXHAUST AIR REQUIREMENTS After defining the appropriate cooking load category, the next step is to calculate the amount of air volume needed for exhaust. This amount is expressed in cubic feet per minute, or CFM. To determine the total exhaust volume of air required, multiply the appropriate CFM by the length of the hood. CFM data is found on the CFM Chart on page 2-9 (Exhaust CFM per linear foot). This CFM Chart defines the minimum exhaust requirement for each cooking load category for wall, island, and exhaust only style hoods. As an example: GWC-9 (Wall mounted Supply & Exhaust Hood), 10' long x 4'-6" deep over medium cooking load Minimum exhaust air required for correct performance is 3000 CFM (10' x 300 CFM per linear foot = 3000). DETERMINING SUPPLY AIR REQUIREMENTS Specific GREASE MASTER models have been tested by Underwriters Laboratories to ascertain the maximum supply air capacity for each. Therefore, it is necessary that the hood model be chosen before deciding upon the supply air requirements. After selection of the hood style, size, and model, the correct supply CFM can be chosen from the CFM Chart. For instance, using the same GWC-9 10' x 4'-6" hood above designated for service over a medium cooking load would require a maximum of 1900 CFM, supply air (10' x 190 CFM per linear foot = 1900).
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CFM CHART
BASED UPON UNDERWRITERS LABORATORIES TESTS (UL 710) UL710 ASSUMES DRAFT FREE CONDITIONS MINIMUM EXHAUST AND MAXIMUM SUPPLY CFM'S FOR MAKE UP AIR HOODS MINIMUM EXHAUST CFM'S FOR ALL EXHAUST ONLY HOODS
Model
Minimum
GSW and GSI 1, 2, 3, or 4 GWC and GIC 2 or 11 GWC and GIC 1,3,4,5 or 7 GWC and GIC 9 or 10 VBS-1, or 4 VBX or VBS-2, or 11 GLA GLA-2
1
Maximum
------100% 5 100% 5 100% 5 1882 2113 150 190 150 150 247 247 --100% 5 ----400 600 7004 400 600 7004 600 600 7004 400 600 7004 400 7004 400 7004 400 400
2402 2703 420 277 345 420 470 533 452 506 107 134
Directed into the hood and/or out the bottom. CFM's listed above are for internal only (Models GWC and GIC 1,5,7 or 10 or VBS 1 may have additional air out the front and are capable of 100% make-up air)
2 3 4 5
Consult factory for application guidelines Capable of supplying 100% make up air
Quantities shown are for Wall Mounted Hoods. Island Style Hoods, GIC or GSI, require the above quantities to be doubled. Exceptions are VBS & VBX Typical exhaust CFM per linear foot for compensating hoods less GWC-2 and GWC-11: Light Duty = 250, Medium Duty = 300, Heavy Duty = 350 Typical exhaust CFM per linear foot for exhaust only hoods plus GWC-2 and GWC-11: Light Duty = 200, Medium Duty = 250, Heavy Duty = 300 See page 2-6 for a list of appliances rated at Light, Medium, Heavy and Extra Heavy Duty Increase exhaust CFM per linear foot if drafts will be present. Reduce exhaust CFM per linear foot if side skirts are used.
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VALUES FOR HOOD AND DUCT STATIC PRESSURES: Hood static pressure: (Measured at hood duct collars with standard 16 filters.) Model GSW,GWC,GSI,GIC Duty Light Medium Heavy Extra Heavy Medium Extra Heavy Medium Extra Heavy Medium Medium Exhaust CFM per Foot 250 300 350 351 and over 470 533 452 506 125 150 Supply CFM per Foot 188 211 212 and over 247 WC (at exhaust collar) .42 .60 .82 Consult Factory .58 .75 .60 .75 .60 .86 WC (at exhaust collar) .15 .20 Consult Factory .13
Duct static pressure: (Supply and Exhaust) Straight Duct: Negligible pressure loss is experienced in straight runs of duct (under 5-0). Straight runs over 5 will incur .0025 of loss per foot. Duct Elbows: Static pressure varies depending upon elbow configuration. Elbow Angle 90 Degrees 45 Degrees 30 Degrees Inches of Exhaust .20 .10 .05 Inches of Supply .10 .05 .03
Example: 10 x 4-6 Canopy Hood GWC-4 Medium Duty Exhaust duct 20 with two 90 degree elbows Supply duct 30 with one 90 degree elbow and two 45 degree elbows Solution: Static Pressure for Exhaust Fan: Hood Static Pressure Duct Static Pressure Duct = 20 x .0025 Elbows = 2 (90 degree) x .20 Total (add the static pressure) Static Pressure for Supply Fan: Hood Static Pressure Duct Static Pressure Duct = 30 x .0025 Elbows = 1 (90 degree) x .10 2 (45 degree) x .05 Total (add the static pressure) .20 .075 .100 .100 .475 .60 .05 .40 1.05
Fan performance charts generally reflect static pressure in .125 increments. Thus, when using these charts, select the next highest static pressure value shown; e.g., .85 use 7/8 static pressure; .475 use 1/2 static pressure.
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DUCT COLLAR SIZING Supply and exhaust collars are points at which duct connections are made to the hood. It is critical that collar sizes be correctly established, as this aspect contributes to satisfactory hood performance. Incorrect sizing can lead to too little or too much velocity through the hood, creating difficulties in capture. The sizes can be selected from the chart below, using CFM values for exhaust and/or supply air. Keep in mind that to maintain optimum operating velocities, use the smaller size collar when the exhaust air quantity falls between stated ranges. Conversely, for supply use the larger size collar.
Exhaust Velocity 1800 FPM Typical CFM/Outlet 900 1200 1500 1800 2100 2400 2700 3000 3300 3600 3900 4200 4500 4800 5100 5400 5700 6000 6300 6600 6900 7200 DXW 12" X 6" 12" X 8" 12" X 10" 12" X 12" 12" X 14" 12" X 16" 12" X 18" 12" X 20" 12" X 22" 12" X 24" 12" X 26" 12" X 28" 12" X 30" 12" X 32" 12" X 34" 12" X 36" 12" X 38" 12" X 40" 12" X 42" 12" X 44" 12" X 46" 12" X 48"
Supply Velocity 1200 FPM Maximum CFM/Outlet 355-535 536-800 801-1250 1251-1835 1836-2750 2751-4200 DXW 8" X 8" 8" X 12" 10" X 15" 10" X 22" 10" X 33" 12" X 42"
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B. CODES
Specific GREASE MASTER hoods have undergone tests and been approved by the following testing agencies: Underwriters Laboratories UL Listed Exhaust Hood Without Exhaust Damper
Underwriters Laboratories UL Listed Canadian Listing Exhaust Hood Without Exhaust Damper
GREASE MASTER hoods are built in compliance with the National Fire Protection Association Bulletin #96 (NFPA 96)
Section 1 of this catalogue provides a more thorough explanation of these code authorities and their functions. Unique code requirements exist in various parts of the country and should be taken into consideration when selecting hood styles, sizes, and air quantities. The factory should be consulted for clarification if there are any questions regarding the existence of special code compliance requirements.
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Welding:
Heliarc- all external welds are liquid tight, polished.
Lights:
UL Listed incandescent vapor proof fixture(s) shock resistant globes mounted on 3' centers (approximate). (Bulbs not included)
OPTION Materials:
14, 16, 18 gauge stainless, aluminized steel.
Wiring:
Pre-wired to junction box -Electrical connections in field by others.
Lights:
UL Listed recessed fluorescent or recessed incandescent fixture(s) vapor proof, fully gasketed, stainless trim, lexan polycarbonate diffuser. (Bulbs not included)
Grease Filters:
UL Classified aluminum baffle type.
Grease Filters:
UL Classified stainless steel, Teflon coated steel, Teflon coated steel with spark arrestor.
Canopy Height:
24 Nominal
Insulation:
Both walls of supply plenum supplied with 1 thick, 3 lb. density foil backed rigid fiberglass board.
Canopy Height:
Closure panel or special heights available.
Stand Off:
3 to 6 separator provided where codes dictate separation between hood and mounting surface Optional insulation available; Stand Offs are made of same material as hood.
Fire Dampers:
In compliance with NFPA-96 requirements, supply fire dampers are provided in all make up air models except GWC and GIC 2 and 11.
Control Panel:
Pre-wired, with stainless steel face plate. Separate toggle switches with indicator lights for exhaust and supply fans. A label identifying each function is included. (Remote mount panel available)
Grease Troughs:
Supplied of material corresponding to hood.
Fire Protection:
Fire Protection system available. See section 12. Fire cabinets available on end of hood.
Grease Cups:
Stainless steel, removable.
Duct Collars:
Exhaust Flanged: - 3 high; Supply: - 5 high.
Hanger Brackets:
Welded to top of canopy for use with full threaded rod (rod provided by others).
Other:
Backsplash Panels, Enclosure Panels, Side Skirts, Fire Cabinet, and UL Listed Fire Dampers in Exhaust Collars also available.
GREASE MASTER RESERVES THE RIGHT TO CHANGE DESIGNS AND OR SPECIFICATIONS WITHOUT PRIOR NOTICE
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