2012 RESNET Conference Austin, TX

Transcription

1 2012 RESNET Conference Austin, TX

2 CONTACT INFO Joe Kuonen CleaResult Consulting Bill Spohn TruTech Tools, LTD

3 AGENDA OVERVIEW Market Drivers Central A/C Rx Measurements The Business case: Success Stories Questions and Answers

4 Introductions Who we are Who YOU are What are you looking to learn this morning?

5 This Session: Using a simple 3 step process technicians can quickly Evaluate, Optimize, and Verify peak AC system performance time-effectively, even in less than ideal conditions.

6 This Session: The tools used allow techs to See the science" Test quickly and accurately Better understand what corrective measures are necessary Gather the evidence needed to present to the owner/get authorization for repairs Important to realize NONE of this is necessary If systems get designed, installed, commissioned and serviced correctly. Ok.

7 This Session: Contractors currently using this system in utility-sponsored programs are Achieving higher customer satisfaction Closing new maintenance agreements, re-engaging cancellations Realizing increased sales opportunities Minimizing call-backs Establishing a Technician accountability process Commissioning new installs and verifying capacity, EER Receiving utility incentives toward tool purchase, completed tune-ups and commissionings

8 What s all the fuss about? Some estimates show that 55% of the capacity of the electrical grid is used for ACR. 10% is used for the 33,000 supermarkets alone Some estimates show that the efficiency of energy delivery is only 19% from energy input to end use Therefore for every KW saved 4-5 times the power plant output is saved Reduces the need for more power plants ($, ROI) Impacts the consumption of fuel (for non-nuclear plants) Impacts the stack emissions facts Courtesy Dave Boyd, Appion, Inc.

9 What s that got to do with you? Estimates show that ~37% of ACR energy used is wasted due to improper service procedures! A California a study showed ~60% of 4000 homes were incorrectly charged and impacted efficiency by 25% or more

10 What s the future? Power usage is expected to increase 46% increase by 2030 The grid was developed decades ago ( ) Since development grid usage is up 1315% Capital expenditures to maintain the grid have dropped 22% (1979 to 1999) In 1999 an estimated 1 billion dollars lost in productivity due to power outages In 2004 power outages cost approximately $ 20 billion In 2008 it rose to approximately $ 80 billion

11 GULP! 90 Billions

12 Why are utilities interested in AC? Why are utilities interested in this? Demand side reduction for peak load times Increasing customer satisfaction PUCs are forcing the hands of utilities Benefits to peak load reduction: if all A/Cs are running due to weather fewer are running simultaneously since individual A/C system operations & delivery are more efficient and matched to load This helps to shave the peaks

13 What are the alternatives? What is the alternative to best practices? More power plants. NIMBY!

14 Broader applications Not just residential: commercial customers and contractors can benefit too. The physics basically scales up

15 Often referred to as a Pre-season checkup May merely confirm that: System is running and cooling somewhat Operating within reasonable voltage ranges Thermostat is functioning and unit is responding Condenser is somewhat clean and free of debris Contactors are clean and functioning Refrigerant pressures are within expected range Wiring and connections are OK, safe

16 In addition, some technicians may: Inspect filter for condition Clean and flush condensate drain line Remove debris from overflow pan, check pitch Inspect blower for cleanliness Check temperature drop across evaporator Inspect/repair vapor line insulation Confirm operation of reversing valve (heat pump)

17 Traditional view of the Basic Refrigeration System Suction Line Cool superheated vapor, usually insulated 1 COMPRESSOR Creates a Pressure Difference Discharge Line Very hot superheated vapor 4 EVAPORATOR Absorbs Heat Sealed and charged with refrigerant 2 CONDENSER Rejects Heat Distributor Connection between metering device and evaporator coil, very cold saturated liquid. 3 METERING DEVICE Creates Pressure Drop Liquid Line Warm, subcooled liquid

18 The Air Conditioner is a SYSTEM It includes the: Condenser Evaporator Refrigerant lines (split systems, not package unit) Air handler (furnace or indoor blower) Entire duct system from return to supply registers

19 THE PROBLEM WITH AIR CONDITIONING 1. It has to be installed. That s where it starts to fall apart. 2. It has to be serviced. That s where it gets even worse.

20 What might be skipped? Measuring airflow? Cleaning dirty e-coils and blowers? Inspecting the duct system for breaks & leaks? Measuring static pressure? Verifying actual delivered capacity & efficiency? Measuring refrigerant charge with digital accuracy? Adjusting charge to Superheat or Subcool?

21 THE ONLY TWO THINGS You can adjust to make an Air Conditioner PERFORM 1. Refrigerant charge 2. Airflow assuming it has been sized correctly

22 Unfortunately 50% of that equation gets ignored 99% of the time!

23 By doing so, the technician gives up 50% of his power to control the outcome of his visit

24 That s like Playing a basketball game with just 3 players on your team Starting a road-trip with ½ your sparkplugs missing Going to a gunfight with only 3 bullets in your six-shooter IT AIN T GONNA WORK SO GOOD!

25 An often overlooked fact It is not possible to correctly charge a system with refrigerant if it does not have proper airflow Checking and adjusting the refrigerant charge of a system before verifying adequate airflow is pointless

26 Common enemies of airflow Improper duct design and construction (undersized return grills, chases, & ducts; undersized supply duct system, kinked flex duct or excess flex length) Restrictive filters Closed dampers, blocked supply grills Clogged or dirty filters, coils, blowers Improper blower speed setting

27 Possible airflow corrective measures Clean Blower Clean E-coil Install less restrictive filter(s) Clean return & supply grills Install larger or additional return grills Install larger or additional return ducts Repair kinked, crushed ducts Remove excess flex length Install larger or additional supply ducts & grills Install turning vanes Open dampers Install new E-coil Replace transition to coil Increase blower speed Perform duct leakage tests Seal return duct leaks Seal supply duct leaks

28 Filtration or strangulation?

29 Look for dumb and obvious stuff Obstructed returns (furniture, boxes) Squashed supply grills, covered w/ rugs

30 What s lurking behind that grill? Obstruction AND Indoor Air Quality issues

31 A close look at a dirty coil

32 Distribution problems can defeat even the best equipment! Check for duct leaks, disconnects, insulation, damage Under-sized or restricted returns Restrictive, high-static filters (electrostatic or some pleated types, permanent filters) Static pressure measurements can point you in the next directiond

33 Restrictive electrostatic filter: You may need to prove resistance to homeowner in order to make them change Without filter: 60 Pa /0.24 IWC With filter: 120 Pa /0.48 IWC But Paul Harvey said.

34 Free area to match pressure drop caused by filter

35 Restricted return chase

36 Undersized filter grills, return chases and ducts The REAL rules of thumb (Manual D condensed) Filter grills: 1.0 to 1.5 sq. ft./ton Return ducts and chases: 85 to 100 sq. in./ton

37 The Kinked Hose Syndrome

38 Visual duct leakage inspection You can spot many serious duct leakage problems without doing a test If you don t go, you don t know! Physical damage (crushed, broken, etc.)

39 Ducts in poor condition

40 Mashed & Disconnected

41 Failure to communicate

42 Read the signs: dirty insulation indicates return leaks Undersized return duct increases pressure on leaks.

43 Return leaks to attic at top plate of chase

44 WHAT S UP??!!

45 Gross return chase leakage to crawl

46 Life-threatening return leaks

47 Duct insulation inadequacies (outside of conditioned space) Gaps, missing, damaged Vapor barrier (white vinyl and paper are NOT good vapor barriers) Condensation damage

48

49 Filet of Duct with Orange Sauce

50 Peeking Duct

51 Verify that total system airflow is within + or 10% of design (nominally 400 cfm/ton) THEN check refrigerant charge What results might we expect? What changes in performance, efficiency, and comfort might we expect?

52 Results Average increase in Delivered Cooling: 27.2%! Hundreds of $ savings per system Often less than a 1- year payback per system Less trouble-calls and maintenance costs Fewer replaced parts Less Guessing; Get it right the first time!

53 Results Average reduction of kw/ton in peak demand (res. & comm.) (99% confidence from a 7500-TU sample) Average of kwh savings annually (A/Cs only; Heat pumps higher)

54 Wake-up call Many of these have been regularly maintained by the industry! How can this happen?

55

56 BENEFITS TO YOU AND YOUR CUSTOMER Enhanced customer services Additional revenue stream Additional work for Off-peak seasons Identify problems that can bite you! Fewer callbacks Differentiation in the Marketplace Become a Participating Contractor Offer Utility Coupons to help them buy it!

57 The view from Diagnostics-based Contracting: Homes & Businesses with Problems = Opportunities = Customers = $ales / Profits / Growth / Reputation

58 Tuneup Analysis Results Example Pre- and Post test of a system Pre-test: 44% of system rated capacity Post-test:100% of system rated capacity HOW DID IT HAPPEN? LET S TAKE A LOOK:

59 Selected Pre-test data 1112 CFM for a 5-ton system (56% of design) Static Pressure: Ret = 0.54 Supply = 0.52 Total static = 1.05 Delivered Capacity = 26,521 Btu (44%) Superheat = 42.1 deg.; target = 20 deg. Delta-T across evaporator = 4.9 deg. Delta-h = 5.3 HOW MANY TECHS HAVE THIS INFORMATION BEFORE MAKING A DECISION ON A COURSE OF ACTION?? (20 mins.)

60 Selected Post-test data 2014 CFM for a 5-ton system (100% of design) Static Pressure: Ret = 0.53 Supply = 0.47 Total static = 1.0 Delivered Capacity = 59,997 Btu (100%) Superheat = 18.0 deg.; target = 20 deg. Delta-T across evaporator = 20.6 deg. Delta-h = 6.62

61 Tuneup Analysis Results Example Pre- and Post test of system So, HOW die we get from Pre-test: 44% of system rated capacity TO: Post-test:100% of system rated capacity Improvements performed: Cleaned blower Increased blower speed to proper setting Added 2 lbs. of R-22 on a 5-ton system Digitally-accurate charge to superheat on correct airflow

62 Sample of 59 Hi-Perf. tune-ups at ASU 50 tons of additional delivered capacity 28% average increase in delivered capacity from Pre- to Post Total increase of 21% of rated capacity Typical Actions taken: Clean condenser Clean evaporator coil and blower Change filter as needed Adjust refrigerant as needed

63 Range of tools and equipment Importance of accuracy, repeatability and reliability Measurements and measurement technology Refrigerant pressure (line temperature) Airflow Humidity Electric Current Issues: Lousy tools Lack of target measurements Lack of understanding

64 Accuracy is key to useful measurements Reasons FOR taking measurements I can prove the system operates as the manufacturer intended I know where to start troubleshooting I can eliminate false causes I have a paper trail of my work I can get better factory support when needed It helps me sleep well at night

65 Typical measuring technology Mechanical manometers Mechanical gauge set P/T charts Digital Thermometer Sling Psychrometer

66 Inherent inaccuracies (mechanical) Reading errors (parallax or fluttering) Any mechanical needle or fluid measure Human errors Gauge accuracy +/-3%, +/-2%, +/-3 % (At best!!!) Calculation errors Technician speed vs. system speed Eg. Timing a superheat reading Speed reading the sling psychrometer Calibration errors Repeatability Lack of procedures in general What about: Beer Can Cold?

67 Analog refrigeration gauges Are using the same technology for the last century and a half! Albeit, today more precisely manufactured With much care can produce readings that are OK Were in specification when they left the factory Only to +/-3%, +/-2%, +/-3 % But is close enough, good enough?

68 In 1849 the Bourdon tube pressure gauge was patented in France by Eugene Bourdon. It is still one of the most widely used instruments for measuring the pressure of liquids and gases of all kinds, including steam, water, and air up to pressures of 100,000 pounds per square inch. Eugene Bourdon founded the Bourdon Sedeme Company to manufacture his invention. The American patent rights to Eugene Bourdon's gauge were bought by Edward Ashcroft in Ashcroft played an important role in the widespread adoption of steam power in this country. He renamed Bourdon's gauge, the Ashcroft gauge.

69 THE Program Toolkit

70 So, what can we do? 1. Verify airflow: digital vane anemometer or other airflow measurement device 2. Verify static pressure is within range 3. Visual inspection of duct inadequacies 4. Measure return and supply wet-bulb and dry-bulb, calculate delivered capacity, compare to rated capacity 5. Recommend corrective actions 6. Recommend digital refrigerant gauges be used for better accuracy

71 Digital RSA Digital refrigeration system analyzer Plus- or Minus 0.5% accuracy Measures to 0.1 Psig and 0.1 degree Fahrenheit Calculates Superheat, Subcool to 0.1 degree Programmed-in charts for 30 refrigerants Displays Evaporator and Condenser saturation temperatures

72 Welcome to the next level! A digital window into AC/R systems Superior accuracy Greater speed Real-time calculations All-in-one tool Confidently charge at low ambient temps Leading to: Fewer call-backs Increased profitability A laboratory accurate instrument designed for rugged use in the field

73 Digital Vane Anemometer for measuring airflow to 0.1 cfm

74 The beauty of the fan The volume of air will not be effected in a given system because a fan will move the same amount of air regardless of the air density. In other words, if a fan will move 3,000 cfm at 70 F it will also move 3,000 cfm at 250 F Photo: GREENHECK FANS

75 Air Density matters If fans move a constant CFM independent of air density They can measure airflow independent of air density also!!! Density +/- 10% Inaccuracy of airflow measurement +/- 5% This does not account for error in the measurement process, only the calculation!!!

76 The Large Vane Advantage True velocity measurement No air density correction required Simple one hand operation Easy to carry and operate Required for proper commissioning of residential systems Low battery consumption Averages true flow over a sample area, not just responding to local stray eddies.

77 Traverse of return grill

78 Digital Manometer for measuring Static Pressure / estimate airflow

79 Static Pressure Drop How it works The Static pressure half of a Pitot tube Need to measurements of static pressure over a know air flow resistance Benefits Low cost Easy to set up and use Need a digital manometer, too Limitations Results depend on the equipment mfr tables The known resistance often changes wet coil how wet is wet, dirty coils Velocity drag at walls of duct Applications In duct measurement SP1 RESISTANCE SP2

80 Checking static pressure

81 The Videoscope for inspecting coils and blowers

82 The Humidity Stick Dry-bulb & wet-bulb temps of Return & Supply Air 0.1 F Wetbulb Temperature difference results in 0.1 ton cooling difference Problems inherent with instrumentation lead to misdiagnoses. Technician after technician should get the same measured results. Technicians should be able to make equipment operate in the field as well as it did in the lab!!! (You need lab accurate instruments to do it!!!)

83 Checking volts and amps

84 Best Practices 3 step process Test in ID problems & repair Test out

85 Calculating Equipment Capacity 1. Measure CFM Entering and leaving wet bulb 2. Find change in enthalpy (Δh) 3. Capacity calculation BTUh = 4.5 x CFM x Δh*** Tons = BTUh/12,000 ***Adjust the constant if outside of standard air!!!

86 Calculating Delivered Capacity from 3 measurements Return: WB F; look-up enthalpy (h) from chart. Return Enthalpy: Supply: WB F; look-up enthalpy (h) from chart. Sup. Enthalpy: Δh = BTUh output = 4.5 x measured CFM x Δh; BTUh = 4.5 x CFM* x Δh = Delivered Percentage of Rated Capacity: Delivered BTUh / Rated BTUh x 100 = %

87 Refrigerant Charge The second adjustable parameter in a refrigeration system Charge is critical 0.5 ounce can make a huge difference with cap tubes or short orifices (pistons) Overcharging is just as bad as undercharging. Both cause a decrease in system efficiency.

88 Actual Load Load is dependent upon the heat in the air and the volume of air passing over the coil evaporator. (Latent and Sensible) The capacity of a refrigeration system can be affected by the load. The less heat available for removal, the slower the heat transfer process will occur.

89 Measuring airflow is easy. Measuring airflow accurately can be very difficult Improve efficiency install 13 seer equipment Accurate airflow measurement now mandatory. Airflow measurement must be: repeatable, accurate, and representative of mass flow If not, will result in calculations not representative of systems efficiency, capacity or latent sensible split and resulting humidity removal. Without proper airflow equipment efficiency and operation are compromised resulting in unsatisfactory equipment operation. Without proper airflow, what is the point?

90 Where you are makes a difference Hard Ducted systems Flex Duct Proximity to transitions in ducts

91 System Performance Performance cannot be assumed!!! Performance varies with load conditions Equipment performance does not assure delivered performance Systems are field installed and require a field commissioning procedure Efficiency and performance go hand in hand

92 THEN Using the information to diagnose problems and make wise choices

93 Building a program to deliver Tons of this service to consumers (Residential & Commercial)

94 Understanding the Tune-Up Season Tune-ups (Green) decreased as daily high temps (Blue) increased (OG&E HEEP Program, implemented by CLEAResult; 2011)

95 Number of Tune-ups CoolSaver Program Growth - AR 3500 Entergy Arkansas CoolSaver Tuneups Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month

96 Entergy Arkansas CoolSaver 2011 Results 3011 Tuneups 1112 kw Peak reduction 1,750,000 kwh savings $426,575 incentives paid

97 Cumulative Tune-ups CoolSaver Program Growth - OK 1600 AEP PSO CoolSaver Tune-ups Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month

98 AEP-PSO CoolSaver 2011 Results 1417 Tuneups 820 kw Peak reduction 1,219,755 kwh savings $185,825 incentives paid

99 Cumulative Tune-ups CoolSaver Program Growth Texas AEP-TCC AEP Texas CoolSaver Tune-ups Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month

100 AEP-TCC CoolSaver 2011 Results 1247 Tuneups 570 kw Peak reduction 1,431,018 kwh savings $173,175 incentives paid

101 Cumulative Tune-ups CoolSaver Program Growth SWEPCO-TX 450 SWEPCO Texas CoolSaver Tune-ups Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month

102 AEP-SWEPCO-TX CoolSaver 2011 Results 392 Tuneups 152 kw Peak reduction 305,859 kwh savings $46,875 incentives paid

103 Total results for all 4 programs (2011) 6,067 Tuneups 2.67 MW Peak reduction 2,969,755 kwh savings $832,450 incentives paid

104 Now How do we turn this into a new profit center in our business?

105 The Status Quo, Rights and Wrongs Historically measurements were not made due to expense and time Also, until the last 5 years, good measurements were hard to make, usually done in lab Bad measurements were made and did not yield results and measurements were abandoned A resurgence of good measurements, now in the field, is under way!

106 INGREDIENTS of a Successful program AND it doesn t happen by itself! Interested customers Active program sponsor: Utility or state (or local) energy office (municipals, co-ops, etc.) Interested contractors Business training Mindset change Technical Training Proper tools

107 What makes the difference Experienced Energy Services Company (ESCO) A thorough, customized process The glue that holds it all together and makes the program happen A responsive support structure and process

108 Contractor Success stories Higher customer satisfaction Better profits Excited technicians Better reputation More confidence from equipment manufacturers More confidence from technicians Improved reputation Business Impact for contractors and Utilities Program feedback and business model changes

109 CONCLUSIONS: So Therefore. Training need Contractors don t know what they should know Business model changes

110 Consequences If you don t LOOK - MEASURE - ID PROBLEM You might as well leave the scene before you commit a crime! Manufacturers and distributors can avoid a black eye for poor quality that they are NOT responsible for What would the world be like if 100,000 systems were improved, a million, 5 million, 100 million?