Energy Recovery Leads to Utilities and Maintenance Savings

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1 GAPPA 2016 Spring Conference Energy Recovery Leads to Utilities and Maintenance Savings Presented by: Mark Williams Augusta University Craig White Thermal Recovery Systems Brandon Scott BL Harbert International

2 ENERGY RECOVERY WHEELS (Heat Wheels) Developed and implemented for various Air Handling Units in order to Capture the energy (Temperature/Heat) being exhausted in order to re-introduce the energy to condition space Simple concept of saving energy

3 HEAT WHEEL BASIC PRINCIPAL

4 ENERGY RECOVERY WHEELS SHORT TERM Energy Savings LONG TERM Maintenance Issues Continued Increases in Repairs and Maintenance Cost for Proper Operation The Question Has the cost of maintenance and operation overshadowed the energy savings?

5 RESULTS Increase in Maintenance Cost for Proper Operation of Energy Recovery Wheels Institutions have Removed Sections of the Heat Wheels Removed the Wheels Entirely from their Air Handling Units Adopted and/or Implemented Less Effective Energy Recovery Processes

6 FACILITIES OPERATIONS Low Static Pressure Condition Developing from Wheel Media Collapsing Removal of Pie Sections of the Energy Recovery Wheel or Entire Wheel Interdisciplinary Research Facility - Expansion (CAII) Removed Sections to Improve Static Pressure

7 SECTION REMOVAL Pieces of the Pie Cut Out

8 CANCER RESEARCH CENTER Constant Maintenance Issues Seven Wheels Check Heat Wheel Surface Area, Guide Rollers, Bearings, Drive Belt, Gear-motor, Belt, and Air Seals for Dirt, Dust, and Debris - Clean Areas as Needed

9 MAINTENANCE SCHEDULE Check Heat Wheel Surface area, Bearings, Drive Belt, Gear-motor, and Air Seals for dirt, dust, and debris, clean areas as needed with a vacuum or low PSI compressed air. Be careful not to damage corrugations (flutes)! Check non-contact multi-pass labyrinth rubber seal for damage, replace as needed. Check gap between wheel and labyrinth rubber seal with seal holding clip or 18 Gauge sheet metal as the gap gauge, adjust seal as needed. 90-Day Inspection Check List Located the highest or protruding section that is on the heat wheel. Adjust all casters at that point with a gap of 18 gauge sheet metal or use the clip from the labyrinth seal. Adjust each of the casters at this point, 4 casters on each side of the heat wheel. Inspect the pillow block wheel bearings for heat and damage. Grease pillow block wheel bearings. Check Idler, Idler arm, tension springs, tension arm, pulley, belt, and verify proper operation of these components and look for any possible damage, replace as needed. Check motor base for damage, tighten mounting bolts as needed, check junction box cover to insure it is secured, check motor for any unusual heat or vibration, and check gear head on motor for excessive heat or vibration. If motor and gear-head are not functioning properly, replace gear-motor assembly. Check Controller and Variable Speed Drive (VSD) for proper operation.

10 MAINTENANCE SCHEDULE Drive motor and gearbox are due for overhaul. 3-Year Inspection Check List Send off drive motor and gearbox assembly to a manufacturer recommend service center for overhaul. The drive motor is integrated with grease or oil lubricated type speed reduction gears and an electric motor in one body assembly. Grease or oil lubrication is factory installed in the gearbox and the motor bearings. Units are rated for approx. 20,000 hours or 3 to 5 years of operation. A periodic overhaul of the drive motor is recommended to extend the life of this assembly.

11 PREVENTIVE MAINTENANCE Problem Up-Keep on Wheels was Consuming Supervision & Maintenance Staff Resources Solution Augusta University found Not all Heat Recovery Wheels are Equal This Effective Method of Capturing Heat can be Achieved to Save Energy with Little Cost to Maintenance and Operation

12 RESOURCES Development of Heat Wheel Specifications With Limited Facilities Staffing Levels, Partnerships Should be Considered for Creating Heat Wheel Specifications Engineering Manufacturers Suppliers

13 SPECIFICATIONS Addressing Maintenance New external bearings may be of the same rating as the old providing they were properly sized to provide a minimum L-10 life of 1,000,000 hours of operation and are changeable without a complete disassembly of the rotor. The seals shall be of a maintenance free "non-contact" type with a 4- pass labyrinth "turbine" for optimum performance and designed to eliminate wear and excessive drag. The seals shall be adjustable and set to within 1/32 inch of the rotor surface and must be bolted to the frame to eliminate seal movement. The seal system must be able to withstand a pressure difference up to 12 in. wc.

14 SPECIFICATIONS Addressing Maintenance The drive system must be gravity tensioned and shall use 2 standard "B" section V- belts that must ride in a groove in the rotor rim to eliminate any side-to-side movements and slippage. The speed reducer must be grease lubricated, maintenance free with a flexible Love-Joy input coupling for easy motor separation and for absorption of any shock or vibration. The drive system shall be easily accessible and visible for inspection and maintenance and have a minimum life expectance of 50,000 hours. The entire rotor and wheel assembly shall require only limited maintenance of biannual greasing of the main bearings and inspection of the drive system. A standard 10-year material and labor warranty shall be provided covering all materials supplied and installed.

15 SPECIFICATIONS Addressing Maintenance The spokes shall be made of extruded aluminum with an "I" beam shape to limit deflection of the rotor to 1/32 inch for the maximum rated airflow. The heat transfer media shall be the industry standard of 200 mm. in depth. Non- standard depths shall be unacceptable. The heat transfer media shall be made out of corrugated aluminum foil with a high surface area per volume and laminar flow to assure that no fouling occurs on the internal heat transfer surface. Dry particles up to 900 microns shall pass freely through the media. All edges shall have an anti-corrosion epoxy coating.

16 CANCER RESEARCH CENTER (CN) Make-up Air Units Serving roughly 169,200 Square feet of Space The Seven Units - width 15 feet - Height of 13 feet Length 27 feet 75 HP Motor - Supply fan Motor roughly 43,000 AFCM 40 HP Motor - Exhaust fan Motor roughly 21,000 AFCM

17 CANCER RESEARCH CENTER (CN) Seven Make-up Air Units

18 CANCER RESEARCH CENTER (CN) Make-up Air Units

19 IRC EXPANSION Make-up Air Units (CAII) Serving roughly 116,000 Square Feet of Space Four Units - Width of 12 feet - Height 12 feet Length 25 feet 75 HP Motor - Supply fan Motor roughly 40,000 CFM 50 HP Motor - Exhaust fan Motor roughly 37,000 CFM

20 IRC EXPANSION Four Make-up Air Units

21 PROJECTS: REPLACE HEAT WHEELS Old Heat Wheels Removed New Heat Wheels Installed Cancer Research Center Common Duct HVAC System One Unit Shutdown at a time to Replace the Wheels Interdisciplinary Research Facility- Expansion (CAII) Common Duct HVAC System One Unit Shutdown at a time to Replace the Wheels

22 CANCER RESEARCH CENTER (CN) Project: Replace Heat Wheels DELIVERY

23 CANCER RESEARCH CENTER (CN) Project: Replace Heat Wheels INSPECTION

24 CANCER RESEARCH CENTER (CN) Project: Replace Heat Wheels REMOVAL AND DISPOSAL OF EXISTING

25 CANCER RESEARCH CENTER (CN) Project: Replace Heat Wheels STAGING

26 CANCER RESEARCH CENTER (CN) Project: Replace Heat Wheels INSTALLATION

27 CANCER RESEARCH CENTER (CN) Condition of Heat Wheels Presently COMPLETED REPLACEMENT

28 PRESENT MAINTENANCE NEW HEAT WHEELS 1.Check Heat Wheel Surface area, Bearings, Drive Belt, Speed Reducer, motor, dust, and debris, clean areas as needed with a vacuum. Be careful not to damage media (flutes)! 2. Main Rotor bearings (Dodge Pillow Block Bearings) should be greased every 6 months with a small amount of Dow Corning Molycote BR2 Plus Grease Day Inspection Check List 3. Wipe off any excess grease to avoid grease from being blown on wheel or transferring to wheel in any source. 4. Inspect motor, Speed Reducer, and Love Joy Coupling for any possible problems. 5. Motor has sealed bearing, permanently lubricated and Speed Reducer has seal lubricated components with a typical life span of 5 to 10 years. 6.Check motor for any unusual heat or vibration. 7. Check Drive belt tension system for problems. This system uses gravity to apply tension to the belt. 8.Check belt, check belt connector, and sheave condition. 9. Belt fasteners are manufacturer Flexco Fasteners: B437, Holder: B43755, & Rocker Pin Tool: B Check Controller and Variable Speed Drive (VSD) for proper operation.

29 IRC EXPANSION Heat Wheel Data Pruett, Ford and Associates, Inc. Current system configuration (after adding the exhaust fans and replacing the ERU wheels), the ERUs provide about 240 tons of pre-cooling to the incoming air on a design 95 degree day. Energy Savings of Roughly 844 kwh or 2,879,848 Btu

30 PROJECT COST IRC Expansion - Retrofit Four Make-up Air Units with New Heat Wheels Funding Portion Energy Recovery Wheels - $219,696 CRC - Retrofit Seven Make-up Air Units with New Heat Wheels Funding Portion Energy Recovery Wheels - $415,899

31 CONCLUSION Question Has the cost of maintenance and operation of Heat Wheels overshadowed the energy savings? Our Answer Not at Augusta University

32 YOUR QUESTIONS Thank You

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