# US Department ofEnergy Workshop on Water Heaters Comments Received on WaterHeater Analysis
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# Comment Issues

Engineering (venting, heattraps, hot water usage and insulation blowing agent) Small water heater closets Price and markup (gas equipment markups and installation costs) Marginal energy rates LCC analysis (RECS data and blended fuel projections) National energy savings analysis (fuel switching) Measured EF versus rated EF Standards recommendation

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# Engineering Issues Venting Comment: GAMA claims recovery efficiency (RE) should not exceed 76% to maintain adequate margin ofsafety. Bradford White says 78% is maximum to avoid corrosion invent; ACEEE believes 80% is viable. Response: 78% RE is 5.5% below the Fuel Loss Efficiency limit for condensation inthe vent system as determined by GRI. 

### Heat traps Comment: DOE should use the same, lower, values for the effect ofplastic and metal heattraps on energy factor than used inthe analysis. Response: Data provided by GAMA and Bradford White are being considered.

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# Engineering Issues Hotwater usage Comment: DOE does nothave sufficient data on each ofthe factors considered to model hot water use, it should consider household size only. Response: Theprinciple factor inthe hot water usage model is household size. The model is applied to RECS data, which showthat households with gas waterheaters are on average larger thanthose with electric water heaters. Comment: Do we account for impact ofpossible clothes washer standards? Response: No.

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# Engineering Issues
Insulation Blowing Agents Comment: DOE should perform life-cycle-cost and national energy savings analyses with HFC-245fa as well as water-blown foam. Response: DOE will add HFC-245fa analyses.

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# Small * WaterHeater Closets

Comment: Consumer choice ofcertain types ofwater heaters, e.g., tabletop or "lowboy" electric waterheaters 36" or less inheight, may be reduced or eliminated by thicker insulation. Response: In our analysis, we have added installation costs for 10 percent ofthe water heaters inside the house this number is larger than the market share oflowboys. We believe that manufacturers also can address this issue intheir design process.

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# Price and Markup
Gas equipment markup Comment: Gas water heatermarkup is too low; themarkups for gas and electric should bethe same. Response: Based on industry data, we find different markups for gas, electric and oilwater heaters.

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# Price and Markup Installation costs Comments: We received comments on the differences in installation costs among gas, electric, and oil; that installation and maintenance costs for gas and oil are too low; andthatwe should add cost for condensate removal. Response: Installation costs are based on information from plumbers and waterheater distributors. Assumptions: Electric: $160 to remove and replace doorjamb on 10% ofwater heaters inside thehouse. Gas: Type B vent costs for 78% RE and Type B ventplus chimney relining for 80% RE in 25% ofhomes above 5000 HDD. No condensation with gas or oilwater heaters

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# Marginal Energy 

# Rates
Comment: Consumer marginal energy prices are notbeing calculated correctly for either gas or electricity, e.g., Inflator93 and fixed costs. Response: We calculated marginal energy prices for each household based onRECS 1993. Comment: Does DOE use different distribution curves for marginal electric prices? Response: Yes, we develop separate curves for summer and winterrates.

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# Life-Cycle-Cost 

# Analysis RECs Data Comment: Why isn't DOE using the mostrecent RECs data? Response: Detailed 1997 RECS database notyet released, we are considering using these data forthe final rule. Comment: RECS database mayhave errors, e.g., incorrect fuel type. Response: RECS database provides broadest range ofdata available onU.S. households.

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# Life-Cycle-Cost 

# Analysis RECs Data, cont'd Comment: Analysis uses household characteristics not found in the database. Response: Volume inferred from small/medium/large categories. Thermostat setpoint temperature, cold water inlettemperature, and room airtemperature calculated using climate andhousehold heating degree days. 

### Naturalgas and LPG priceprojections Comment: DOE appears to beusing ablended price projection. Response: Weused fuel prices from each RECS household and corrected themto 2003 prices.
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# National Energy Savings Fuel switching Comment: It appears the analysis is biasedtoward showing impacts on fuel switching. Response: In the analysis, wetake current market share ofwater heaters, by fuel type, and assume fuel switching may occur only innew construction, andthat in existing households, waterheaters are replaced with the same fuel type.

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# Measured EF vs. Rated EF

Comment: Rated EF's are higher forhigh efficiency electric water heaters than models andtesting would predict. What is DOE going to assume, rated ortested values, for the analysis? Response: Based on available data, DOE believes high efficiency water heaters are overrated by approximately 0.02 EF. DOE willuse the lower values in its analysis.

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# Standards Recommendation
Comment: GAMA suggested a standard ofEF = 0.88 and 0.57 for electric and gas water heaters, respectively. Response: These are approximately equal to trial standard level 2.

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