Rating the dehumidification performanceof cooling equipmentArmin RuddResidential Building Energy Efficiency Meeting 201022 July 2010; 9:10 am

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Residential Building Energy Efficiency Meeting 201022 July 2010

Where we have been

Demonstrated that there is a certain need for dehumidification separate from cooling in high-performance, low-sensible-gain houses in humid climates.

Worked with builders and manufacturers providing: Stand-alone dehumidifier solutions

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Residential Building Energy Efficiency Meeting 201020 July 2010

Dehumidifier and ventilation duct in interior mechanical closet with louvered door

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Residential Building Energy Efficiency Meeting 201022 July 2010

Where we have been

Demonstrated that there is a certain need for dehumidification separate from cooling in high-performance, low-sensible-gain houses in humid climates.

Worked with builders and manufacturers providing: Stand-alone dehumidifier solutions Dehumidifiers connected to the central space

conditioning system (Aprilaire Whole-house Dehumidifier)

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Residential Building Energy Efficiency Meeting 201020 July 2010

Ducted dehumidifier in conditioned spacewith living space control

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Residential Building Energy Efficiency Meeting 201022 July 2010

Where we have been

Demonstrated that there is a certain need for dehumidification separate from cooling in high-performance, low-sensible-gain houses in humid climates.

Worked with builders and manufacturers providing: Stand-alone dehumidifier solutions Dehumidifiers connected to the central space

conditioning system (Aprilaire Whole-house Dehumidifier)

Supplemental dehumidification integrated into the space conditioning system (AAON heat pump with modulating condenser reheat)

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Residential Building Energy Efficiency Meeting 201022 July 2010

DX heat pump with modulating hot gas condenser reheat for dedicated dehumidification mode

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Residential Building Energy Efficiency Meeting 201022 July 2010

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901 27 53 79 105

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AAON Heat Pump with modulating condenser reheat testing23-Sep-2008 (JD 266)

RA temp

RA rh

SA temp

Total W-h/min

Dehumidifier mode

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Residential Building Energy Efficiency Meeting 201022 July 2010

Where we are now, and ongoing

Continuing supplemental dehumidification system testing and optimization

Creating a framework in which to better evaluate the performance of a range of cooling and dedicated dehumidification equipment as they are applied to high-performance homes. Developing the engineering criteria for obtaining standardized

extended performance data in testing laboratories Conducting field and laboratory evaluations to validate the

viability of obtaining and utilizing the performance data Working with ASHRAE and AHRI on industry consensus test

method and performance rating standards

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Residential Building Energy Efficiency Meeting 201022 July 2010

Regional ratings may be important

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Residential Building Energy Efficiency Meeting 201022 July 2010

Method of Testing for Rating Residential Dehumidifiers for Moisture Removal Capacity and Moisture Removal Efficiency FORWARD … 1. PURPOSE 1.1. The purpose of this standard is to prescribe test methods for determining the moisture removal capacity and moisture removal efficiency for residential dehumidifiers. 2. SCOPE 2.1 This Standard applies to residential dehumidifying equipment that removes moisture by cooling air below its dew-point. The equipment may consist of one or more separate assemblies located indoors or outdoors. Where more than one separate assembly is used, they shall be designed to be used together. 2.2 For purposes of this standard, residential dehumidifiers provides air dehumidification and may provide additional functions of: air cooling, air heating, air circulation, air filtration, air-to-air heat recovery, and water heating. 3.1 DEFINITIONS

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Residential Building Energy Efficiency Meeting 201022 July 2010

ARI Standard 210/240 test conditions

Table 3. Cooling Mode Test Conditions for Units Having a Single-Speed Compressor and a Fixed-Speed Indoor Fan, a Constant Air Volume Rate Indoor Fan, or No Indoor Fan

Test Description F C F C F C F C

A Test - required (steady, wet coil) 80 26.7 67 19.4 95 35 75.0(1) 23.9(1) B Test - required (steady, wet coil) 80 26.7 67 19.4 82 27.8 65.0(1) 18.3(1) C Test - optional (steady, dry coil) 80 26.7 82 27.8 D Test - optional (cyclic, dry coil) 80 26.7 82 27.8

Notes: (1) The specified test condition only applies if the unit rejects condensate to the outdoor coil.

Cd = degradation coefficient, you want that to be low, default=0.25PLF = part load factor (at 50% load), you want that to be high

PLF = 1 - 0.5(Cd)

SEER = PLF * EER

Air Entering Indoor Unit Dry-Bulb Wet-Bulb Wet-BulbDry-Bulb

Air Entering Outdoor Unit

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Residential Building Energy Efficiency Meeting 201022 July 2010

Humidity control setpoints for testing

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Residential Building Energy Efficiency Meeting 201022 July 2010

Humidity control setpoints for testing

Outdoor IndoorT/RH/Tdp T/RH/Tdp(F/%/F) (F/%/F)

Test 1 95/58/78 80/60/65 cooling design conditions78/55/6175/50/55

Test 2 80/85/75 80/60/65 cooling part-load: summer nights/rainy periods78/55/6175/50/55

Test 3 75/85/70 78/60/63 cooling part-load: spring/fall78/55/6175/50/55

Test 4 65/90/62 72/60/57 no cooling: spring/fall/winter70/52/5268/45/46

Test 5 (opt) 65/55/491 cold climate basement conditions1 Single unit basement dehumdifier condition

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Residential Building Energy Efficiency Meeting 201022 July 2010

Dehumidification equipment test results

Indoor Indoor Indoor Sensible Latent Heat Moisture Moisture Dehum EnergyOutdoor Return Supply Wet-coil Cooling Cooling Added Removal Total Removal Efficiency Efficiency

T/RH/Tdp T/RH/Tdp T/RH/Tdp Airflow Capacity Capacity In Dehum Capacity Power Efficiency1 (MRE) Ratio (DER) Ratio (EER)(F/%/F) (F/%/F) (F/%/F) (cfm) (Btu/h) (Btu/h) (Btu/h) (L/h) (kW) (L/kW-h) (Btu/W-h) (Btu/W-h)

Test 1 95/58/78 80/60/6578/55/6175/50/55

Test 2 80/85/75 80/60/6578/55/6175/50/55

Test 3 75/85/70 78/60/6378/55/6175/50/55

Test 4 65/90/62 72/60/5770/52/5268/45/46

Test 5 (opt) 65/55/49

1 Same as the Energy Factor used for dehumidifiers by Energy Star

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Residential Building Energy Efficiency Meeting 201022 July 2010

Further cost reduction of dehumidifying equipment through design and manufacturing optimization

More buy-in from cooling equipment manufacturers regarding the need for a focus on dehumidification performance

More laboratory and field testing of cooling and dehumidifying equipment to establish better performance maps for simulation models

New performance rating standard (and possibly new method of test) for cooling and dehumidifying equipment to aid in proper humidity control design and equipment selection A Method of Test route with specified test conditions was rebuffed by

ASHRAE A new effort will begin with AHRI to develop an industry consensus

rating standard that will specify more test conditions and test results

Gaps, Barriers, and Future Work