Presentation on theme: "2005 Title 24 Nonresidential Acceptance Requirements Mechanical Designer Training Presented by Tav Commins California Energy Commission."— Presentation transcript:
2005 Title 24 Nonresidential Acceptance Requirements Mechanical Designer Training Presented by Tav Commins California Energy Commission
2 Overview First Energy Codes for California developed in 1973. Code is updated every three years. Residential Code and Nonresidential Code
3 Overview Two ways to comply (Prescriptive and Performance) Prescriptive – Listed values for efficiency of equipment, walls and the maximum amount of glass that may be installed. Performance – The building is modeled using a approved computer program.
4 Overview All conditioned buildings must comply with the energy code. All nonconditioned commercial buildings must comply with the indoor lighting requirements.
5 Overview October 1 st 2005 latest code revision went into place. Commercial and Residential buildings now require verification that key pieces of equipment were installed properly.
6 When must the tests be conducted? All new construction In existing buildings when that piece of equipment is replaced.
7 Overview Building Efficiency is a product of: Design, materials & equipment Installation and set-up Occupant patterns and control Traditional standards Specify materials, equipment, controls Law of diminishing returns for more eff equip 2005 Title 24 Part 6 Energy Standards Assure equipment works as intended
8 What is Acceptance Testing? Two components of acceptance testing Construction inspection Is the specified equipment that is required to be installed actually there Equipment testing Does the equipment work as intended Functional “performance” tests Does Not replace commissioning Commissioning – broader scope
9 Project Overview Definition of Acceptance Testing Requirements Acceptance Testing requirements are defined as the application of targeted inspection checks and testing to determine whether specific building systems conform to the criteria set forth in the Standards and to the plans and specifications.
10 Is Acceptance Testing Needed? PIER Small Commercial HVAC survey http://www.energy.ca.gov/reports/2003-11-17_500-03-082.PDF Small commercial buildings < 4 yrs old 64% of economizers failed Cooling energy increased by 37% 38% of supply fans cycling during occupancy Violation of Title 24, §121(c)1 30% unoccupied fan operation Increase of fan and heating energy 8% no outside air 8% simultaneous heating and cooling
11 What Systems are Included HVAC All packaged HVAC systems All built-up HVAC systems Hydronic systems Lighting Controls
12 Acceptance Tests Required self-certification that equipment was tested and works as intended by the Standards Liability trail results from cheating on test Only one test (air distribution efficiency-leakage) requires 3rd party testing Home Energy Rating Service (HERS)
13 Resources 2005 Building Energy Efficiency Standards for Residential and Nonresidential (Title 24) 2005 Nonresidential Energy Compliance Manual Chapter 4 – Mechanical Systems Chapter 8 – Acceptance Requirements End of Manual - Compliance and Acceptance Forms CEC Resources http://www.energy.ca.gov/title24 CEC Bldg Standards Hotline (800)772-3300
14 Acceptance Chapter (Chapter 8) Nonresidential Manual Overview of compliance process At-A-Glance - 2 page overview of test Purpose Estimated Time Benefits Warnings or Cautions Instrumentation Test conditions Acceptance Criteria Detailed test description
15 Acceptance and Compliance Forms Found in Appendix A of the Nonresidential Manual Compliance forms Filled out by designer MECH-1-C (C for compliance) Acceptance Forms Filled out by person conducting test Usually contractor, TAB or commissioning agent MECH-1-A (A for acceptance)
16 Compliance Forms Compliance documentation with equipment specification and forms MECH-1-C lists all tests and which equipment must by tested MECH-1-C lists designated personnel to perform tests MECH-3-C lists design minimum outside air Criteria for outside air tests (NJ.3.1 & 3.2)
17 Acceptance Forms Installing contractor or other “eligible professional” conducts tests and fills out MECH-#-A acceptance forms Equipment test - until it passes all tests Completed forms handed to inspector along with other documentation Certificate of Occupancy Granted
18 Designer Has a Big Impact on Ease and Cost of Acceptance Tests Designer clearly identifies tests Problem if covered equipment not specified on MECH-1-C form and later needs testing Designer specifies equipment Pre-calibrated equipment is cheaper Designer builds in test capabilities Test ports and pre-installed gages Valves for isolating equipment
19 Key Statements in MECH-1-C The plans meet code I am qualified to sign these forms List of all mechanical acceptance tests with blanks for: Equipment to be tested Who will test equipment Installing Contractor Design Professional Agent Selected by Owner
20 MECH-1-C Note to Bidders “Since the MECH-1-C will be part of the plans, completion of this section will allow the responsible party to budget accordingly” Be careful to budget appropriately Make note of this section to potential bidders
23 People Certified to Perform Tests The installing contractor, engineer of record, TAB contractor, or owner’s agent (i.e. 3 rd party Cx provider) The building inspector has the authority to require the Acceptance Agent to demonstrate competence, to his/her satisfaction
24 Equipment Specification Equipment specification can reduce level of acceptance testing and cost Thermostats with Pre-programmed schedules Factory calibrated sensors with documentation Pressure sensor for Variable Frequency Drive (VFD) control Air flow monitoring station Demand Control Ventilation (DCV) CO 2 sensor calibrated ± 75 ppm Supply water temp reset sensor Alternative is field calibration against reference sensor by using acceptance protocols
25 Air-side acceptance test forms Acceptance FormsACM Section and Test MECH-2-A NJ 3.1 Variable Air Volume Systems Outdoor Air NJ 3.2 Constant Volume Systems Outdoor Air MECH-3-ANJ 4.1 Constant Volume Packaged HVAC Systems MECH-4-ANJ 7.1 (Air-side) Economizer MECH-5-ANJ 5.1 Air Distribution MECH-6-ANJ 8.1 Demand Control Ventilation MECH-7-ANJ 9.1 Supply Fan Variable Flow Controls
26 Hydronic Acceptance Forms Acceptance FormsACM Section and Test MECH-8-A NJ 10.1 Variable Flow Controls NJ 10.2 Automatic Isolation Controls NJ 10.3 Supply Water Temperature Reset Controls NJ 10.4 Water-loop Heat Pump Controls NJ 10.5 Variable Frequency Drive Controls
27 MECH-2-A Outside Air Same form used to document outside air acceptance for: CAV – constant air volume NJ.3.2 VAV – variable air volume NJ.3.1 Measured minimum outside air must be within 10% of design minimum outside air Test and Balance (TAB) contractor is probably the best qualified and has proper flow measurement tools available
28 MECH-2-A VAV Outdoor Air “Sensor used to control outdoor air flow must have calibration certificate or be field calibrated” Air flow monitoring station Pressure across dedicated fixed damper
29 MECH-2-A VAV Outdoor Air Contractor must set minimum outdoor air within 10% of design outdoor air at full flow and at minimum flow Control strategies discussed in Mechanical Chapter of Nonresidential Manual
30 MECH-2-A Outside Air Measurement Calibrated air flow station Pitot traverse in a straight section of duct Pitot traverse across O/A inlet
31 MECH-3-A Constant Volume Packaged HVAC Test Thermostats or zone temperature control Thermostat or zone temperature sensor is located in zone served by unit T-stat has capability of 5º deadband between heating and cooling Occupied, unoccupied and holiday schedule programmed One hour pre-occupancy “purge” – turns on fans 1 hour before occupied. Set-up and set-backs programmed as per design instructions
32 MECH-3-A Constant Volume Packaged HVAC Systems Residential thermostats won’t work Occupied: Fan must run continuously Unoccupied: Fan runs intermittently to supply load Timed manual override of unoccupied settings Outside air damper position Minimum position during occupied period Closed during unoccupied periods Test likely conducted by HVAC contractor and perhaps Controls contractor
33 MECH-4-A Economizer Construction Inspection Likely performed by HVAC contractor High limit setpoint not greater than listed in Table 144-C per Standards Section 144(e)3 High limit sensors are factory calibrated with calibration certificate or field calibrated. Which is easier?
34 MECH-4-A Economizer Construction Inspection Integrated economizer §144(e)2B Capable of providing partial cooling even when additional mechanical cooling is needed to meet the load EMS systems – cooling coil modulates to provide remainder of load Stand-alone systems – two stage thermostat is minimally compliant When outdoor air temp below high limit, economizer provides 1 st stage cooling When O/A > high limit first stage of cooling provided by compressor 2 nd stage of cooling provided by compressor
35 MECH-4-A Economizer Equipment testing Not required if economizer is factory installed and tested Attach manufacturer’s certification Field installed or if no factory certification Simulate cooling load and enable economizer O/A damper opens, return damper closes and relief is provided by relief damper or exhaust damper Mechanical cooling enabled only if economizer can’t meet load Simulate cooling load and disable economizer O/A damper closes, return damper opens Mechanical cooling enabled
36 MECH-5-A Air Distribution §144(k) Small (<5,000 sf) CV systems only When > 25% of duct surface is outdoors or in unconditioned space Place greater than 75% of ducts under insulated roof – test not needed Ducts must be tested for duct leakage by the installing contractor and verified by a 3 rd party HERS rater.
37 MECH-5-A Construction Inspection Drawbands Stainless steel worm drive or UV resistant nylon duct ties Must use UL 181 tape or mastic Cloth backed duct tape not used unless with drawbands and mastic R-8 insulation on all ducts in unconditioned spaces
39 MECH5-A Leakage Test New Construction Rated flow from capacity 400 cfm/ton 21.7 cfm/kBtuh heating only systems Seal all diffusers Pressurize system to 25 Pa (0.1 in WC) with fan with calibrated orifice (duct blaster) Measured leakage no greater than 6% of rated flow Conducted by HVAC contractor. Must seal all leakes Verified by HERS rater
40 MECH-5-A Duct Sealing on Retrofits §144(k), 149(b)1D&E Applies to small Constant Volume system with ducts in unconditioned spaces when: Any amount of ducts replaced or added, or Changeout of HVAC system, or Major repair (new condenser, new coil) Existing ducts: Leakage ≤15% of rated supply flow, or >60% reduction of leakage prior to sealing ducts with all visible leaks sealed, or Can’t access the ducts and all visible leaks are sealed as certified by a HERS rater Exceptions Asbestos Existing ducts that were previously certified
41 MECH-6-A Demand Control Ventilation Likely conducted by controls contractor Construction Inspection Sensor mounted in room between 1 and 6 ft from floor Calibration Factory calibrated with manufacturer’s certification of ± 75 ppm accuracy Field calibrated using reference gas or reference sensor Which is easier?
42 MECH-6-A DCV Equipment Test Simulate a high CO2 load Decrease CO2 setpoint or breathe on sensor Outside air damper modulates open To design outside air setting from MECH-3-C Simulate a low CO2 load Increase CO2 setpoint, don’t breath on sensor Outside air modulates to minimum position
43 MECH-7-A Supply Fan Variable Frequency Drive Construction inspection Factory calibrated pressure sensors with certificate (don’t lose these!) Field calibration against a reference sensor Equipment testing Full flow – all boxes calling for cooling Measured pressure within 10% of control pressure Reduced flow – boxes not calling for cooling Measured pressure within 10% of control pressure Reduced flow pressure ≤ full flow pressure
44 MECH-8-A Hydronic Tests Construction inspection Confirm piping, sensors and controls are located as shown on plans Sensors are factory calibrated or field calibrated Temperature for temperature reset Pressure for VFD control
45 Summary Acceptance tests assure that your design intent for energy savings is executed Most automatic controls have an associated acceptance test The designer identifies which tests get applied to which equipment on the MECH-1-C form Construction bids need to account for the costs of conducting and documenting the acceptance tests Specifying factory calibrated and factory installed equipment can dramatically reduce testing costs Some designs reduce the amount of testing needed ducts run under an insulated roof factory installed economizers
46 Resources – 2005/2008 Standard Energy Efficiency Hotline Open 8:00 to 12:00 and 1: to 4:30 E-mail: email@example.com Phone: 916-654-5106 or Phone: 1-800-772-3300 http://www.energy.ca.gov/title24/ http://www.energy.ca.gov/title24/ California Commissioning Collaborative www.cacx.org