RFMA 2016 March 13 15, 2016

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1 Is Your Restaurant s HVAC Perfectly Tuned To Sing Your Praises? DIY Checkpoints And Fixes For HVAC Audits Sam Rayburn Melink Test & Balance Agenda Overview of building pressure Symptoms of negative building pressure Cost implications of an unbalanced building Causes of an unbalanced building Poor conditions to look for Steps to bring building back into balance Helpful tools for HVAC audits Selecting the right HVAC contractor With the help of a tune up 1

2 HVAC can sing your praises The goal is a positive building pressure Outside Air = CFM Exhaust Air = CFM Positive Pressure = +250 CFM + Symptoms of an Out-of-Tune (Negative Pressure) Building Hot in summer, cold in winter Back draft from the water heater Entry doors hard to open (kids, elderly) Condensation drips from diffusers Poor smoke capture Humidity Hidden energy, O&M, and other costs can go undetected for years until they are discovered in a retrocommissioning project. Without retro commissioning or a TAB check, the extra costs are never found, and the owner pays high utility costs unnecessarily built into an operating budget. Dave McFarlane, Environmental Engineering, The High Cost of Improperly Balanced Buildings 2

3 The Cost of Improperly Balanced Buildings Study published in Consulting Specifying Engineer Magazine, Dave McFarlane 100,000 sq. ft. building Design Airflow: 110,000 CFM Design Motor Load: 110 Horsepower Actual Motor Load: 180 Horsepower Operates: 16 hr/day, 5 day/week Energy cost: $.08/kWh Actual Airflow: 130,000 CFM Issue Yearly Cost Savings 20-Yr Cost Savings Excessive fan air flow $17,400 $350,000 Excessive reheat requirements $25,000 $500,000 Excessive fan static pressure $5,500 $110,000 Excessive exhaust makeup air $25,000 $500,000 costs Excessive pump static pressure $3,000 $60,000 Leaky reheat valves causing a 3 F $14,800 $300,000 air temp rise Total $90,700 $1,820,000 What about for a restaurant? 2012 RFMA Webinar: How Buildings Breathe Charles Dugo, Bloomin Brands David Harrison, D R Management Enterprises Our data from over 1,800 utility bills suggests that electric is inflated as much as 20% when operating a restaurant with a negative balance pulling in unconditioned air. Watch the archived seminar on RFMA s website for an AWESOME example of how to use a T&B Report What Causes a Restaurant to Become Unbalanced? 1. Equipment deficiencies 2. Improper preventative maintenance 3. Kitchen staff fiddling 3

4 11 Common Causes of an Out-Of-Tune HVAC System 1. Exhaust Fans in Poor Condition 2. Supply Air Leaking Above Ceiling 3. OA Dampers Improperly Installed 4. Exhaust Fans Not Sealed To Curb 5. RTU Compartment/Coil Dirty 6. Tops of Diffuser Not Insulated 7. Filters Improperly Sized For Hoods 8. Exhaust Fans Not Hinged 9. MUA Not Operating Properly 10. Dirty Indoor/Outdoor Filters 11. Worn/Broken Belts Exhaust Fans in Poor Condition Reduced exhaust airflow Clean or replace fan Supply Air Leaking Above Ceiling Loss of airflow and energy Connect duct and seal leaks 4

5 Outside Air Dampers Disabled Building not pressurized Repair outside air intakes and/or dampers Exhaust Fans Not Sealed To Curb Loss of airflow and poor smoke capture Seal gaps in duct and fan to curb RTU Blower Compartment and/or Coil Dirty Reduced airflow, contaminated air Clean internal components of RTU 5

6 Tops of Diffuser Not Insulated Condensation forms on diffusers Insulate tops of diffusers Filters Improperly Sized For Hoods Poor grease containment Install correct size/type filters Exhaust Fans Not Hinged Fire hazard, poor airflow Install hinge kit on fan and clean 6

7 MUA Not Operating Properly Building not pressurized Check operation of MUA unit Improperly Placed Sensors/Equipment Inaccurate temperature reading Relocate equipment or sensor Dirty Indoor/Outdoor Filters Reduced airflow Replace/clean filters 7

8 Worn/Broken Belts Reduced or no airflow Replacing belts Steps To Get The HVAC Back In Tune 1. Ask the Restaurant 2. Turn on HVAC Equipment 3. Check Building Pressure 4. Observe Smoke Capture 5. Check for Comfort (Drafts) 6. Inspect the Roof 7. Determine Intervention Plan 1. Ask the Restaurant Inquire about any concerns Ask employees about comfort issues Comments about temperature? Complaints from patrons Examples Drafts Doors hard to open Poor smoke capture Insects Odors Humidity 8

9 2. Turn on HVAC Equipment Exhaust Fans On Make up Air Fans On Thermostats Programmed Properly Operating times & temperatures programmed Check thermostats for Fan ON 3. Check Building Pressure Check airflow at door Check airflow at drive through window Open entry door a crack and place a lighter in crack. If flame pulls toward inside of building, the building is negative. Checking Building Pressure (By Zone) 1. Exhaust Unwanted Smoke & Odors + 2. Add OA to Pressurize Building 3. Contain Odors to Kitchen & Restrooms 4. Slight Positive Overall + + Net = 5%-10%+ 9

10 4. Observe Smoke Capture Check for good smoke capture Make up air and Exhaust fans are operating Visually inspect exhaust hoods to ensure all smoke is being exhausted Grease filters installed and clean Ensure that all cooking equipment is under hoods with a minimum 6 overhang, but 18 is best practice recommendation Look for stained ceiling tiles Understanding Smoke Capture A = Under Ventilation B = Over Ventilation C = Proper Capture & Containment 5. Check for Comfort (Drafts) RTUs operating Feel for drafty areas Check airflow at diffusers (with ribbon) Are hanging signs swaying? 10

11 6. Inspect the Roof Inspect RTUs for proper operation Dirty filters Worn belts Closed Outside Air Dampers Exposed wiring Inspect EFs for proper operation General appearance Grease accumulation Unusual noise (winding or grinding) 7. Determine Intervention Plan Do It Yourself Building walk thru Fix what you can do yourself (filters, T stats) Develop course of action Call HVAC Contractor Make necessary repairs Replace inoperable equipment Consult T&B Professional Tune up equipment Restore positive building pressure Remedy poor smoke capture Helpful Tools for Troubleshooting What s in Curt s pockets? Curtis Sawan, Red Lobster FM RFMA Member 11

12 Infrared Thermometer Where to buy: Grainger, Lowe s Cost: $40 $150 What to use it for: Inspect temperature air coming out of supply duct. Identify disconnected/broken ductwork Air Balance Anemometer Where to buy: Grainger, testequipmentdepot.com, Amazon.com Cost: $45 $200 What to use it for: Mounts onto smartphone to measure airflow coming out of supply ducts. Identify disconnected/broken ductwork Extender for anemometer Where to buy: testequipmentdepot.com, Grainger Cost: $30 Digital Temp & Humidity pen Where to buy: Amazon, testequipmentdepot.com, Grainger Cost: $50 $80 What to use it for: Measure temperature and relative humidity Selecting the Right HVAC Contractor Trustworthy, reputable (they put quality & integrity first) Independent, objective (they work directly for you) Experienced (they know your building & systems) Licensed, certified OSHA certified, safety program Insured In Summary A negative pressure = an out of tune HVAC system Seven steps to a fine tuned building Select the right HVAC contractor Check for HVAC health regularly 12

13 Questions? In the wild world of HVAC, you never know what you may encounter Session Evaluation in Your App Don t Forget! 13