WSR 12-07-017

PERMANENT RULES

BUILDING CODE COUNCIL


[ Filed March 12, 2012, 3:04 p.m. , effective April 12, 2012 ]


     Effective Date of Rule: Thirty-one days after filing.

     Purpose: Making editorial corrections to chapter 51-11 WAC, 2009 Washington State Energy Code, in Sections 503.8.1, 901, 1412.4, and 1436.2.

     WAC 51-11-0503, in Section 503.8.1, redundant language was added to the end of the second paragraph. The requirement for a second seven day programmable thermostat is stricken.

     WAC 51-11-0900, in Section 901, Chapter 6 was added to the charging language to clarify that the use of Chapter 6 for base compliance is allowed.

     WAC 51-11-1412, Section 1412.4 was amended to provide clarity on the requirements applicable to multifamily residential buildings.

     WAC 51-11-1436, a typographical error in Section 1436.2 was corrected.

     Citation of Existing Rules Affected by this Order: Amending WAC 51-11-0503, 51-11-0900, 51-11-1412, and 51-11-1436.

     Statutory Authority for Adoption: RCW 19.27A.020, 19.27A.025, and 19.27A.045.

     Other Authority: Chapters 19.27 and 34.05 RCW.

      Adopted under notice filed as WSR 11-18-086 on September 7, 2011.

     Number of Sections Adopted in Order to Comply with Federal Statute: New 0, Amended 0, Repealed 0; Federal Rules or Standards: New 0, Amended 0, Repealed 0; or Recently Enacted State Statutes: New 0, Amended 0, Repealed 0.

     Number of Sections Adopted at Request of a Nongovernmental Entity: New 0, Amended 4, Repealed 0.

     Number of Sections Adopted on the Agency's Own Initiative: New 0, Amended 0, Repealed 0.

     Number of Sections Adopted in Order to Clarify, Streamline, or Reform Agency Procedures: New 0, Amended 4, Repealed 0.

     Number of Sections Adopted Using Negotiated Rule Making: New 0, Amended 0, Repealed 0;      Pilot Rule Making: New 0, Amended 0, Repealed 0; or Other Alternative Rule Making: New 0, Amended 0, Repealed 0.

     Date Adopted: November 18, 2011.

C. Ray Allshouse

Council Chair

OTS-4110.1


AMENDATORY SECTION(Amending WSR 10-03-115, 10-13-113 and 10-22-056, filed 1/20/10, 6/21/10 and 10/28/10, effective 1/1/11)

WAC 51-11-0503   Mechanical systems.  

     503.1 General: This section covers the determination of design requirements, system and component performance, control requirements, insulating systems and duct sealing. For all other duct construction requirements, refer to the State Mechanical Code (chapter 51-52 WAC).


     503.2 Calculations of Heating and Cooling Loads, and System Sizing Limits: The design parameters specified in Chapter 3 shall apply for all computations.


     503.2.1 Calculation Procedures: Heating and cooling design loads for the purpose of sizing HVAC systems are required and shall be calculated in accordance with accepted engineering practice, including infiltration and ventilation.


     503.2.2 Space Heating and Space Cooling System Sizing Limits: Mechanical systems for all buildings which provide space heating and/or space cooling shall be sized as required in IRC Section M1401.3.


EXCEPTIONS: The following limited exemptions from the sizing limit shall be allowed; however, in all cases heating and/or cooling design load calculations shall be submitted.
1. For equipment which provides both heating and cooling in one package unit, including heat pumps with electric heating and cooling and gas-pack units with gas heating and electric cooling, compliance need only be demonstrated for the larger of the space heating or space cooling load for the selected system size.
2. Natural gas- or oil-fired space heating equipment whose total rated space heating output in any one dwelling unit is 40,000 Btu/h or less is exempt from the sizing limit.
3. Stand-by equipment may be installed if controls and other devices are provided which allow redundant equipment to operate only when the primary equipment is not operating.
4. Electric resistance heaters under 2 kW.

     503.3 Simultaneous Heating and Cooling: Systems and equipment that provide simultaneous heating and cooling shall comply with the requirements in, as appropriate, Section 1422 or Section 1435.


     503.4 HVAC Equipment Performance Requirements: All heating equipment shall meet the requirements of the National Appliance Energy Conservation Act (NAECA) and be so labeled. Equipment shall also comply with Section 1411.


     503.5 Reserved.


     503.6 Balancing: The HVAC system design shall provide a means for balancing air and water systems. Balancing the system shall include, but not be limited to, dampers, temperature and pressure test connections and balancing valves.


     503.7 Cooling with Outdoor Air (Economizer Cycle): Systems and equipment that provide mechanical cooling shall comply with Section 1413 and, as appropriate, Section 1423 or 1433.


     503.8 Controls:


     503.8.1 Temperature Control: The primary space conditioning system within each dwelling unit shall be provided with at least one programmable thermostat for the regulation of temperature. The thermostat shall allow for, at a minimum, a 5-2 programmable schedule (weekdays/weekends) and be capable of providing at least two programmable setback periods per day.

     Each additional system provided within a dwelling unit shall be provided with at least one adjustable thermostat for the regulation of temperature. ((The thermostat shall allow for, at a minimum, a 5-2 programmable scheduled (weekdays/weekends).))


EXCEPTIONS: 1. Systems controlled by an occupant sensor that is capable of shutting the system off when no occupant is sensed for a period of up to thirty minutes.
2. Systems controlled solely by a manually operated timer capable of operating the system for no more than two hours.

     Each thermostat shall be capable of being set by adjustment or selection of sensors as follows:


     503.8.1.1: When used to control heating only: Fifty-five degrees to seventy-five degrees F.


     503.8.1.2: When used to control cooling only: Seventy degrees to eighty-five degrees F.


     503.8.1.3: When used to control both heating and cooling, it shall be capable of being set from fifty-five degrees to eighty-five degrees F and shall be capable of operating the system heating and cooling in sequence. The thermostat and/or control system shall have an adjustable deadband of not less than ten degrees F.


     503.8.2 Humidity Control: If a system is equipped with a means for adding moisture to maintain specific selected relative humidities in space or zones, a humidistat shall be provided. Humidistats shall be capable of being set to prevent new energy from being used to produce space-relative humidity above thirty percent.


EXCEPTION: Special uses requiring different relative humidities may be permitted when approved by the building official.

     503.8.3 Zoning for Temperature Control:


     503.8.3.1 One- and Two-Family Dwellings: At least one thermostat for regulation of space temperature shall be provided for each separate system. In addition, a readily accessible manual or automatic means shall be provided to partially restrict or shut off the heating and/or cooling input to each zone or floor.


     503.8.3.2 Multifamily Dwellings: For multifamily dwellings, each individual dwelling unit shall have at least one thermostat for regulation of space temperature. A readily accessible manual or automatic means shall be provided to partially restrict or shut off the heating and/or cooling input to each room. Spaces other than living units shall meet the requirements of 503.8.3.3.


     503.8.3.3 Control Setback and Shutoff:


     One- and Two-Family and Individual Multifamily dwelling units -- The thermostat required in section 503.8.3.1 or section 503.8.3.2, or an alternate means such as a switch or clock, shall provide a readily accessible, manual or automatic means for reducing the energy required for heating and cooling during the periods of nonuse or reduced need, such as, but not limited to unoccupied periods and sleeping hours. Lowering thermostat set points to reduce energy consumption of heating systems shall not cause energy to be expended to reach the reduced setting.


     503.8.3.4 Systems Serving Multiple Dwelling Units, Guest Rooms, and Common Areas: Systems that serve more than two dwelling units, guest rooms, and common areas shall comply with the control requirements in Sections 1412 and 1432, with the exceptions of Sections 1412.4.2 and 1432.1.


     503.8.3.5 Heat Pump Controls: Heat pumps with supplementary electric resistance heaters shall have controls complying with Section 503.8.1. In addition, controls shall meet the following requirements:


     1. Prevent supplementary heater operation when the heating load can be met by the heat pump alone; and


     2. The cut-on temperature for compression heating shall be higher than the cut-on temperature for supplementary heating, and the cut-off temperature for compressing heating shall be higher than the cut-off temperature for supplementary heating.


     All heat pumps installed under this section shall include the capability to lock out the supplementary heat based on outdoor temperature. This control shall have a maximum setting of 40°F. At final inspection, the lock out control shall be set to 32°F or less.


EXCEPTION: The controls may allow supplementary heater operation during defrost.

     503.9 Air Handling Duct System Insulation: Ducts, plenums and enclosures installed in or on buildings shall be thermally insulated per Table 5-11.


EXCEPTIONS: Duct insulation (except where required to prevent condensation) is not required in any of the following cases:
1. When the heat gain or loss of the ducts, without      insulation, will not increase the energy requirements of the building.
2. Within the HVAC equipment.
3. Exhaust air ducts.
4. Supply or return air ducts installed in basements or cellars in one-and two-family dwellings.
5. The insulation required on supply air ducts may be reduced to R-4 when installed in buffer spaces not intended for human occupancy such as insulation crawl spaces and enclosed attic spaces. The buffer space must be air sealed and insulated to the full value of conditioned spaces.

     503.10 Ducts.


     503.10.1 Installation of ducts in exterior walls, floors or ceilings shall not displace required envelope insulation. Building cavities may not be used as ducts.


     503.10.2 Leakage Testing: Ducts shall be leak tested in accordance with RS-33, using the maximum duct leakage rates specified in Section 503.10.3.


     503.10.3 Sealing: All ducts, air handlers, filter boxes, and building cavities used as ducts shall be sealed. Joints and seams shall comply with Section M1601.3 of the International Residential Code or Section 603.9 of the International Mechanical Code. Duct tightness testing shall be conducted to verify that the ducts are sealed. A signed affidavit documenting the test results shall be provided to the jurisdiction having authority by the testing agent. When required by the building official, the test shall be conducted in the presence of department staff. Duct tightness shall be verified by either of the following:


     1. Postconstruction test: Leakage to outdoors shall be less than or equal to 6 cfm per 100 ft2 of conditioned floor area or a total leakage less than or equal to 8 cfm per 100 ft2 of conditioned floor area when tested at a pressure differential of 0.1 inches w.g. (25 Pa) across the entire system, including the manufacturer's air handler enclosure. All register boots shall be taped or otherwise sealed during the test.


     2. Rough-in test: Total leakage shall be less than or equal to 6 cfm per 100 ft2 of conditioned floor area when tested at a pressure differential of 0.1 inches w.g. (25 Pa) across the roughed-in system, including the manufacturer's air handler enclosure. All register boots shall be taped or otherwise sealed during the test. If the air handler is not installed at the time of the test, total leakage shall be less than or equal to 4 cfm per 100 ft2 of conditioned floor area.


EXCEPTIONS: 1. Duct tightness test is not required if the air handler and all ducts are located within conditioned space.
2. Duct tightness test is not required if the furnace is a nondirect vent type combustion appliance installed in an unconditioned space. A maximum of six feet of connected ductwork in the unconditioned space is allowed. All additional supply and return ducts shall be within the conditioned space. Ducts outside the conditioned space shall be sealed with a mastic type duct sealant and insulated on the exterior with R-8 insulation for above grade ducts and R-5 water resistant insulation when within a slab or earth.

     503.10.4 Dampers: Requirements for Automatic or manual dampers are found in Chapter 15 of the Washington State Residential Code (chapter 51-51 WAC).


     503.11 Pipe Insulation: All piping shall be thermally insulated in accordance with Table 5-12.


EXCEPTION: Piping installed within unitary HVAC equipment.

Cold water pipes outside the conditioned space shall be insulated in accordance with the Washington State Plumbing Code (chapter 51-56 WAC).

[Statutory Authority: RCW 19.27A.025, 19.27A.045. 10-03-115, 10-13-113 and 10-22-056, § 51-11-0503, filed 1/20/10, 6/21/10 and 10/28/10, effective 1/1/11. Statutory Authority: RCW 19.27A.025, 19.27A.045 and chapters 19.27, 19.27A, and 34.05 RCW. 09-06-024, § 51-11-0503, filed 2/23/09, effective 7/1/10. Statutory Authority: RCW 19.27A.022, 19.27A.025, 19.27A.045, and chapters 19.27 and 34.05 RCW. 07-01-089, § 51-11-0503, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27A.020, 19.27A.045. 04-01-106, § 51-11-0503, filed 12/17/03, effective 7/1/04; 02-24-076, § 51-11-0503, filed 12/4/02, effective 5/1/03. Statutory Authority: RCW 19.27A.025, 19.27A.045. 02-01-112, § 51-11-0503, filed 12/18/01, effective 7/1/02; 01-03-010, § 51-11-0503, filed 1/5/01, effective 7/1/01. Statutory Authority: RCW 19.27A.020, 19.27A.045, and 19.27.020. 98-24-075, § 51-11-0503, filed 12/1/98, effective 7/1/99. Statutory Authority: RCW 19.27A.025 and 19.27A.045. 98-03-003, § 51-11-0503, filed 1/8/98, effective 7/1/98. Statutory Authority: RCW 19.27A.025. 93-21-052, § 51-11-0503, filed 10/18/93, effective 4/1/94. Statutory Authority: Chapter 19.27A RCW. 92-01-140, § 51-11-0503, filed 12/19/91, effective 7/1/92. Statutory Authority: RCW 19.27A.020 and 1990 c 2. 91-01-112, § 51-11-0503, filed 12/19/90, effective 7/1/91.]

OTS-4111.1


AMENDATORY SECTION(Amending WSR 10-22-057, filed 10/28/10, effective 1/1/11)

WAC 51-11-0900   Chapter 0900 -- Additional residential energy efficiency requirements.  


901 Additional Residential Energy Efficiency Requirements. Dwelling units permitted under this Code shall comply with all provisions of Chapter 5 or Chapter 6 of this Code and develop 1 credit from Table 9-1.


EXCEPTION: Buildings complying using Chapter 4 Building Design by Systems Analysis shall meet this provision of this section by demonstrating that the proposed building energy use is 8 percent less than the target building energy use.

TABLE 9-1
ENERGY CREDITS (DEBITS)

OPTION DESCRIPTION CREDIT(S)
1a HIGH EFFICIENCY HVAC EQUIPMENT 1:

Gas, propane or oil-fired furnace or boiler with minimum AFUE of 92%,

or

Air-source heat pump with minimum HSPF of 8.5.

1.0
1b HIGH EFFICIENCY HVAC EQUIPMENT 2:

Closed-loop ground source heat pump;

with a minimum COP of 3.3.

2.0
1c HIGH EFFICIENCY HVAC EQUIPMENT 3:

DUCTLESS SPLIT SYSTEM HEAT PUMPS, ZONAL CONTROL:

In home where the primary space heating system is zonal electric heating, a ductless heat pump system shall be installed and provide heating to at least one zone of the housing unit.

1.0
2 HIGH EFFICIENCY HVAC DISTRIBUTION SYSTEM:1

All heating and cooling system components installed inside the conditioned space. All combustion equipment shall be direct vent or sealed combustion.

Locating system components in conditioned crawl spaces is not permitted under this option.

Electric resistance heat is not permitted under this option.

Direct combustion heating equipment with AFUE less than 80% is not permitted under this option.

1.0
3a EFFICIENT BUILDING ENVELOPE 1:

Prescriptive compliance is based on Table 6-1, Option III with the following modifications: Window U = 0.28 floor R-38, slab on grade R-10 full, below grade slab R-10 full.

or

Component performance compliance: Reduce the Target UA from Table 5-1 by 5%, as determined using EQUATION 1.

0.5
3b EFFICIENT BUILDING ENVELOPE 2:

Prescriptive compliance is based on Table 6-1, Option III with the following modifications: Window U = 0.25 and wall R-21 plus R-4 and R-38 floor, slab on grade R-10 full, below grade slab R-10 full, and R-21 plus R-5 below grade basement walls.

or

Component performance compliance: Reduce the Target UA from Table 5.1 by 15%, as determined using EQUATION 1.

1.0
3c SUPER-EFFICIENT BUILDING ENVELOPE 3:

Prescriptive compliance is based on Table 6-1, Option III with the following modifications:

Window U = 0.22 and wall R-21 plus R-12 and R-38 floor, slab on grade R-10 full, below grade slab R-10 full and R-21 plus R-12 below grade basement walls and R-49 advanced ceiling and vault.

or

Component performance compliance: Reduce the Target UA from Table 5.1 by 30%, as determined using EQUATION 1.

2.0
4a AIR LEAKAGE CONTROL AND EFFICIENT VENTILATION:

Envelope leakage reduced to SLA of 0.00020 building envelope tightness shall be considered acceptable when tested air leakage is less than specific leakage area of 0.00020 when tested with a blower door at a pressure difference of 50 PA. Testing shall occur after rough in and after installation of penetrations of the building envelope, including penetrations for utilities, plumbing, electrical, ventilation, and combustion appliances.

and

All whole house ventilation requirements as determined by Section M1508 of the Washington State Residential Code shall be met with a heat recovery ventilation system in accordance with Section M1508.7 of that Code.

0.5
4b ADDITIONAL AIR LEAKAGE CONTROL AND EFFICIENT VENTILATION:

Envelope leakage reduced to SLA of 0.00015 building envelope tightness shall be considered acceptable when tested air leakage is less than specific leakage area of 0.00015 when tested with a blower door at a pressure difference of 50 PA. Testing shall occur after rough in and after installation of penetrations of the building envelope, including penetrations for utilities, plumbing, electrical, ventilation, and combustion appliances.

and

All whole house ventilation requirements as determined by Section M1508 of the Washington State Residential Code shall be met with a heat recovery ventilation system in accordance with Section M1508.7 of that Code.

1.0
5a EFFICIENT WATER HEATING:

Water heating system shall include one of the following:

Gas, propane or oil water heater with a minimum EF of 0.62.

or

Electric Water Heater with a minimum EF of 0.93.

and for both cases

All showerhead and kitchen sink faucets installed in the house shall meet be rated at 1.75 GPM or less. All other lavatory faucets shall be rated at 1.0 GPM or less.2

0.5
5b HIGH EFFICIENCY WATER HEATING:

Water heating system shall include one of the following:

Gas, propane or oil water heater with a minimum EF of 0.82.

or

Solar water heating supplementing a minimum standard water heater. Solar water heating will provide a rated minimum savings of 85 therms or 2000 kWh based on the Solar Rating and Certification Corporation (SRCC) Annual Performance of OG-300 Certified Solar Water Heating Systems.

or

Electric heat pump water heater with a minimum EF of 2.0.

1.5
6 SMALL DWELLING UNIT 1:

Dwelling units less than 1500 square feet in floor area with less than 300 square feet of window + door area. Additions to existing building that are less than 750 square feet of heated floor area.

1.0
7 LARGE DWELLING UNIT 1:

Dwelling units exceeding 5000 square feet of floor area shall be assessed a deduction for purposes of complying with Section 901 of this Code.

-1.0
8 RENEWABLE ELECTRIC ENERGY:

For each 1200 kWh of electrical generation provided annually by on-site wind or solar equipment a 0.5 credit shall be allowed, up to 3 credits. Generation shall be calculated as follows:

For solar electric systems, the design shall be demonstrated to meet this requirement using the National Renewable Energy Laboratory calculator PVWATTs. Documentation noting solar access shall be included on the plans.


For wind generation projects designs shall document annual power generation based on the following factors:

The wind turbine power curve; average annual wind speed at the site; frequency distribution of the wind speed at the site and height of the tower.

[0.5]

Footnotes: 1. Interior Duct Placement: Ducts included as Option 2 of Table 9-1 shall be placed wholly within the heated envelope of the housing unit. The placement shall be inspected and certified to receive the credits associated with this option.
EXCEPTION: Ducts complying with this section may have up to 5% of the total linear feet of ducts located in the exterior cavities or buffer spaces of the dwelling. If this exception is used the ducts will be tested to the following standards:
Post-construction test: Leakage to outdoors shall be less than or equal to 1 CFM per 100 ft2 of conditioned floor area when tested at a pressure differential of 0.1 inches w.g. (25 Pa) across the entire system, including the manufacturer's air handler enclosure. All register boots shall be taped or otherwise sealed during the test.
2. Plumbing Fixtures Flow Ratings. Low flow plumbing fixtures (water closets and urinals) and fittings (faucets and showerheads) shall comply with the following requirements:
(a) Residential bathroom lavatory sink faucets: Maximum flow rate - 3.8 L/min (1.0 gal/min) when tested in accordance with ASME A112.18.1/CSA B125.1.
(b) Residential kitchen faucets: Maximum flow rate - 6.6 L/min (1.75 gal/min) when tested in accordance with ASME A112.18.1/CSA B125.1.
(c) Residential showerheads: Maximum flow rate - 6.6 L/min (1.75 gal/min) when tested in accordance with ASME A112.18.1/CSA B125.1.

[Statutory Authority: RCW 19.27A.025, 19.27A.045. 10-22-057, § 51-11-0900, filed 10/28/10, effective 1/1/11; 10-03-115, 10-13-113 and 10-22-056, § 51-11-0900, filed 1/20/10, 6/21/10 and 10/28/10, effective 1/1/11. Statutory Authority: RCW 19.27A.022, 19.27A.025, 19.27A.045, and chapters 19.27 and 34.05 RCW. 07-01-089, § 51-11-0900, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27A.020, 19.27A.045. 04-01-106, § 51-11-0900, filed 12/17/03, effective 7/1/04. Statutory Authority: RCW 19.27A.025, 19.27A.045. 02-01-112, § 51-11-0900, filed 12/18/01, effective 7/1/02. Statutory Authority: Chapters 19.27 and 19.27A RCW and 1994 c 226. 95-01-126, § 51-11-0900, filed 12/21/94, effective 6/30/95. Statutory Authority: RCW 19.27A.020 and 1990 c 2. 91-01-112, § 51-11-0900, filed 12/19/90, effective 7/1/91.]

     Reviser's note: The brackets and enclosed material in the text of the above section occurred in the copy filed by the agency and appear in the Register pursuant to the requirements of RCW 34.08.040.

OTS-4112.1


AMENDATORY SECTION(Amending WSR 10-03-115, 10-13-113 and 10-22-056, filed 1/20/10, 6/21/10 and 10/28/10, effective 1/1/11)

WAC 51-11-1412   Controls.  


1412.1 Temperature Controls: Each system shall be provided with at least one temperature control device. Each zone shall be controlled by individual thermostatic controls responding to temperature within the zone. At a minimum, each floor of a building shall be considered as a separate zone. Controls on systems required to have economizers and serving single zones shall have multiple cooling stage capability and that activate the economizer when appropriate as the first stage of cooling. See Section 1423 or 1433 for further economizer control requirements.


1412.2 Deadband Controls: When used to control both comfort heating and cooling, zone thermostatic controls shall be capable of a deadband of at least 5 degrees F within which the supply of heating and cooling energy to the zone is shut off or reduced to a minimum.


EXCEPTIONS: 1. Special occupancy, special usage, or code requirements where deadband controls are not appropriate.
2. Thermostats that require manual changeover between heating and cooling modes.

1412.3 Humidity Controls: If a system is equipped with a means for adding moisture, a humidistat shall be provided.


1412.4 Setback and Shutoff: For all occupancies other than Group R, HVAC systems shall be equipped with automatic controls capable of accomplishing a reduction of energy use through control setback or equipment shutdown during periods of nonuse or alternate use of the spaces served by the system. The automatic controls shall:

     a. Have a minimum seven-day clock and be capable of being set for seven different day types per week,

     b. Be capable of retaining programming and time setting during loss of power for a period of at least ten hours, and

     c. Include an accessible manual override, or equivalent function (e.g., telephone interface), that allows temporary operation of the system for up to two hours.


EXCEPTIONS: 1. Systems serving areas which require continuous operation at the same temperature setpoint.
2. Equipment with full load demands of 2 Kw (6,826 Btu/h) or less may be controlled by readily accessible manual off-hour controls.
3. Systems controlled by an occupant sensor that is capable of shutting the system off when no occupant is sensed for a period of up to 30 minutes.
4. Systems controlled solely by a manually operated timer capable of operating the system for no more than two hours.

     For Group R-1 hotel and motel guest rooms, a minimum of one of the following control technologies shall be required in hotels/motels with over 50 guest rooms such that the space temperature would automatically setback (winter) or set up (summer) by no less than 3°C (5°F) when the occupant is not in the room:

     1. Controls that are activated by the room occupant via the primary room access method - key, card, deadbolt, etc.

     2. Occupancy sensor controls that are activated by the occupant's presence in the room.


     For Group R-2 and R-3 dwelling units, the primary space conditioning system within each dwelling unit shall be provided with at least one programmable thermostat for the regulation of temperature. The thermostat shall allow for, at a minimum, a 5-2 programmable schedule (weekdays/weekends) and be capable of providing at least two programmable setback periods per day.

     Each additional system provided within a dwelling unit shall be provided with at least one adjustable thermostat for the regulation of temperature.


EXCEPTIONS: 1. Systems controlled by an occupant sensor that is capable of shutting the system off when no occupant is sensed for a period of up to 30 minutes.
2. Systems controlled solely by a manually operated timer capable of operating the system for no more than two hours.

     Each thermostat shall be capable of being set by adjustment or selection of sensors as follows:

     When used to control heating only: 55°F to 75°F.

     When used to control cooling only: 70°F to 85°F.


1412.4.1 Dampers: Outside air intakes, exhaust outlets and relief outlets serving conditioned spaces shall be equipped with motorized dampers which close automatically when the system is off or upon power failure. Return air dampers shall be equipped with motorized dampers. Stair shaft and elevator shaft smoke relief openings shall be equipped with normally open (fails to open upon loss of power) dampers. These dampers shall remain closed until activated by the fire alarm system or other approved smoke detection system.


EXCEPTIONS: 1. Systems serving areas which require continuous operation.
2. Combustion air intakes.
3. Gravity (nonmotorized) relief dampers are acceptable in equipment with less than 5,000 cfm total supply flow when in buildings less than 3 stories in height.
4. Type 1 grease hoods exhaust.
5. In Group R occupancies dampers shall comply with the requirements of the State Mechanical Code (chapter 51-52 WAC).

Dampers installed to comply with this section, including dampers integral to HVAC equipment, shall have a maximum leakage rate when tested in accordance with AMCA Standard 500 of:

     (a) Motorized dampers: 10 cfm/ft2 of damper area at 1.0 in w.g.

     (b) Nonmotorized dampers: 20 cfm/ft2 of damper area at 1.0 in w.g., except that for nonmotorized dampers smaller than 24 inches in either dimension: 40 cfm/ft2 of damper area at 1.0 in w.g.


Drawings shall indicate compliance with this section.


1412.4.1.1 Damper Controls: Dampers for outdoor air supply and exhaust shall automatically shut when the systems or spaces served are not in use or during building warm-up, cooldown, and setback. Operation of dampers shall be allowed during ventilation prepurge one hour before expected occupancy and for unoccupied period precooling during the cooling season.


     Classrooms, gyms, auditoriums and conference rooms larger than 500 square feet of floor area shall have occupancy sensor control that will either close outside air dampers or turn off serving equipment when the space is unoccupied except where equipped with another means to automatically reduce outside air intake below design rates when spaces are partially occupied.


1412.4.2 Optimum Start Controls: Heating and cooling systems with design supply air capacities exceeding 2,000 cfm shall have optimum start controls. Optimum start controls shall be designed to automatically adjust the start time of an HVAC system each day to bring the space to desired occupied temperature levels immediately before scheduled occupancy. The control algorithm shall, as a minimum, be a function of the difference between space temperature and occupied setpoint and the amount of time prior to scheduled occupancy.


1412.5 Heat Pump Controls: Unitary air cooled heat pumps shall include microprocessor controls that minimize supplemental heat usage during start up, set-up, and defrost conditions. These controls shall anticipate need for heat and use compression heating as the first stage of heat. Controls shall indicate when supplemental heating is being used through visual means (e.g., LED indicators). Heat pumps equipped with supplementary heaters shall be installed with controls that prevent supplemental heater operation above 40°F.


1412.6 Combustion Heating Equipment Controls: Combustion heating equipment with a capacity over 225,000 Btu/h shall have modulating or staged combustion control.


EXCEPTIONS: Boilers.
Radiant heaters.
1412.7 Balancing: Each air supply outlet or air or water terminal device shall have a means for balancing, including but not limited to, dampers, temperature and pressure test connections and balancing valves.


1412.8 Ventilation Controls for High-Occupancy Areas. Demand control ventilation (DCV) is required for spaces that are larger than 500 ft2, have an occupant density for ventilation of greater than 25 people per 1000 ft2 of floor area (based on the Default Occupant Density column of Table 403.3 of the Washington State Mechanical Code), and are served by systems with one or more of the following:

     a. An air-side economizer,

     b. Automatic modulating control of the outdoor air damper, or

     c. A design outdoor ventilation airflow of all systems serving the space combined greater than 3000 cfm.


EXCEPTIONS: 1. Systems with energy recovery complying with Section 1436.
2. Spaces with a combined design outdoor airflow less than 1000 cfm.
3. Spaces where the supply airflow rate minus any makeup or outgoing transfer air requirement is less than 1000 cfm.

1412.9 Enclosed Loading Dock and Parking Garage Exhaust Ventilation System Control. Mechanical ventilation systems for enclosed loading docks and parking garages shall be designed to exhaust the airflow rates (maximum and minimum) determined in accordance with the State Mechanical Code (chapter 51-52 WAC).


     Ventilation systems shall be equipped with a control device that operates the system automatically upon detection of vehicle operation or the presence of occupants by approved automatic detection devices. Each of the following types of controllers shall be capable of shutting off fans or modulating fan speed.


     1. Gas sensor controllers used to activate the exhaust ventilation system shall stage or modulate fan speed upon detection of specified gas levels. All equipment used in sensor controlled systems shall be designed for the specific use and installed in accordance with the manufacturer's recommendations. The following are minimum gas sensor system requirements:


     a. Garages and loading docks used predominantly by gasoline-powered vehicles shall be equipped with a controller and a full array of carbon monoxide (CO) sensors set to maintain levels of carbon monoxide below 35 parts per million (ppm). Spacing and location of the sensors shall be installed in accordance with manufacturer recommendations.


     b. Where more than 20 percent of the vehicles using the garage or loading dock are powered by nongasoline fuels, the area exposed to nongasoline fueled vehicle exhaust shall be equipped with a controller and fuel-appropriate sensors. The set-point for the nongasoline sensors shall be no less than the standard used by OSHA for eight hour exposure. The controller shall activate the ventilation system when sensor set-point is reached. Spacing and location of the sensors shall be installed in accordance with manufacturer recommendations.


     2. Automatic time clocks used to activate the system shall activate the system during occupied periods. The time clock shall be capable of scheduling multiple start and stop times for each day of the week, varying the daily schedule, and retaining programming for a 10-hour period during loss of power.


     3. Occupant detection sensors used to activate the system shall detect entry into the parking garage along both the vehicle and pedestrian pathways.


1412.9.1 System Activation Devices for Enclosed Loading Docks. Ventilation systems for enclosed loading docks shall be activated by one of the following:


     1. Gas sensors; or


     2. Time clock and a manual over-ride switch located in the dock area that is accessible to persons in the loading dock area.


1412.9.2 System Activation Devices for Enclosed Parking Garages. Ventilation systems for enclosed parking garages shall be activated by gas sensors.


EXCEPTION: A parking garage ventilation system having a total design capacity under 8,000 cfm may use a time clock or occupant sensors.

[Statutory Authority: RCW 19.27A.025, 19.27A.045. 10-03-115, 10-13-113 and 10-22-056, § 51-11-1412, filed 1/20/10, 6/21/10 and 10/28/10, effective 1/1/11. Statutory Authority: RCW 19.27A.022, 19.27A.025, 19.27A.045, and chapters 19.27 and 34.05 RCW. 07-01-089, § 51-11-1412, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27A.020, 19.27A.045. 04-01-106, § 51-11-1412, filed 12/17/03, effective 7/1/04. Statutory Authority: RCW 19.27A.025, 19.27A.045. 02-01-112, § 51-11-1412, filed 12/18/01, effective 7/1/02; 01-03-010, § 51-11-1412, filed 1/5/01, effective 7/1/01; 98-03-003, § 51-11-1412, filed 1/8/98, effective 7/1/98. Statutory Authority: RCW 19.27A.025. 93-21-052, § 51-11-1412, filed 10/18/93, effective 4/1/94.]

OTS-4109.1


AMENDATORY SECTION(Amending WSR 10-03-115, 10-13-113 and 10-22-056, filed 1/20/10, 6/21/10 and 10/28/10, effective 1/1/11)

WAC 51-11-1436   Heat recovery.  


1436.1 Fan Systems: Fan systems which have a minimum outdoor air capacity of 5,000 cfm or greater shall have a heat recovery system with at least 50 percent recovery effectiveness. Fifty percent heat recovery effectiveness shall mean an increase in the outside air supply temperature at design heating conditions of one half the difference between the outdoor design air temperature and 65 degrees F. Provision shall be made to bypass or control the heat recovery system to permit air economizer operation as required by Section 1433. Heat recovery energy may be provided from any site-recovered or site-solar source. Where a single room or space is supplied by multiple units, the aggregate ventilation (cfm) of those units shall be used in applying this requirement.


EXCEPTIONS: These exceptions only apply to the particular exhaust subsystems. The remaining cfm of the main supply system is subject to the energy recovery requirements.
1. Laboratory systems equipped with both variable air volume supply and variable air volume or two-speed exhaust fume hoods provided that an instruction label is placed on the face of the hood that provides the information in Exhibit 14-1.

Exhibit 14-1

INSTRUCTIONS TO OPERATOR
To be in compliance with the Energy Code, this fume hood is designed to operate as variable air volume (VAV) by adjusting the sash or controller. Maintain sash in the minimum position during use and close totally when the fume hood is not in use.

2. Systems serving spaces heated to less than 60 degrees F.
3. Systems which can be shown to use as much energy with the addition of heat recovery equipment as without it.
4. Systems exhausting toxic, flammable, paint exhaust or corrosive fumes making the installation of heat recovery equipment impractical.
5. Type I commercial kitchen hoods.
6. Systems that only provide cooling.
7. Cooling only air handling units or air conditioning units where the minimum outdoor air is less than 70 percent of total supply air.

1436.2 Condensate Systems: On-site steam heating systems shall have condensate water recovery. On-site includes a system that is located within or adjacent to one or more buildings within the boundary of a contiguous area or campus under one ownership and which serves one or more of those buildings.

     Buildings using steam generated off-site with steam heating systems which do not have condensate water recovery shall have condensate water heat recovery.


1436.3 Heat Recovery for Service Water Heating: Condenser water heat recovery systems shall be installed for heating or preheating of service hot water provided all of the following are true:

     a. The facility operates 24 hours a day.

     b. The total installed heat rejection capacity of the water-cooled systems exceeds 1,500,000 Btu/h of heat rejection.

     c. The capacity of service water heating equipment exceeds 250,000 Btu/h.

     The required heat recovery system shall have the capacity to provide the smaller of:

     a. 60 percent of the peak heat rejection load at design conditions; or

     b. Preheat of the peak service hot water draw to 85°F; or

     c. 50 percent of the service water heating load.


EXCEPTIONS: 1. Facilities that employ condenser heat recovery for space heating with a heat recovery design exceeding 30 percent of the peak water-cooled condenser load at design conditions.
2. Facilities that provide 60 percent of their service water heating from site solar or site recovered energy or from other sources.

1436.4 Condenser Heat Recovery: Facilities having food service, meat or deli departments and having 500,000 Btu/h or greater of remote refrigeration condensers shall have condenser waste heat recovery from freezers and coolers and shall use the waste heat for service water heating, space heating or for dehumidification reheat. Facilities having a gross conditioned floor area of 40,000 ft2 or greater and 1,000,000 Btu/h or greater of remote refrigeration shall have condenser waste heat recovery from freezers and coolers and shall use the waste heat for service water heating, and either for space heating or for dehumidification reheat for maintaining low space humidity.

[Statutory Authority: RCW 19.27A.025, 19.27A.045. 10-03-115, 10-13-113 and 10-22-056, § 51-11-1436, filed 1/20/10, 6/21/10 and 10/28/10, effective 1/1/11. Statutory Authority: RCW 19.27A.025. 93-21-052, § 51-11-1436, filed 10/18/93, effective 4/1/94.]

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