By 2002, all 20 northwest manufacturers had signed Energy Star partnership agreements. In 2003, BAIHP staff recruited, Flexible Technologies, RADCO, and Friedrich as Energy Star industry partners.

To be Energy Star certified with a heat pump, the heat pump must meet the program specifications. Cost data investigations indicate a $400 incremental cost for an Energy Star heat pump, and coil sizing challenges when retaining the same "footprint." Similar evaluations on 90% efficient gas furnaces (Intertherm M3) will take place in the next reporting period. BAIHP staff now are in the process of evaluating HSPF and SEER ratings for both split and unitary systems to see how reported manufacturer values compare with real world field-collected data.

BAIHP staff visits each of the manufactured housing plants quarterly to verify compliance with SGC/NC/E-Star specifications. Inspections include a plant audit, ventilation system testing, and construction-related troubleshooting with plant staff and independent inspectors. Persistent plant issues include lack of attention to duct installation and sealing, and improper wall insulation sizing which results in installation compression or voids. (Please see Figure 16.)

In December 2002, BAIHP staff conducted a quarterly in-plant inspection at Valley Manufactured Housing in the company of local utilities, DOE, BPA, and PNNL personnel, with the goal of fostering closer ties between the manufactured home industry, regulating agencies, and utilities.

Figure 16. Quarterly plant inspection in the company of representatives from utilities, DOE, BPA and PNNL at Valley Manufactured Housing in Sunnyside Washington.

Refinement of SGC/NC Standards: BAIHP staff have been working to refine existing SGC/NC specifications, in large part to incorporate innovative building technologies researched by BAIHP. As part of the specification revision, BAIHP staff have collaborated with EPA and other regional partners to clarify the equivalency of SGC/NC with Energy Star. This year, BAIHP staff developed a new Energy Star compliance path for climate zone 2 that doesn't require a heat pump. The non-heat pump path uses a heat recovery ventilation system, a .93 EF water heater, and a tighter duct and envelope system.

Energy Conservancy: BAIHP staff worked with the Energy Conservancy to evaluate their new products for measuring air handler and exhaust fan flows.

Fireplace Controls: A 12-volt DC battery backup, charging, and inverter system was installed in the WSU Energy house to operate the propane fireplace during power outages. Tests revealed that the backup system operates the propane fireplace for up to 48 hours during a power outage, while maintaining comfortable indoor temperatures even during severe winter conditions. BAIHP staff have discussed this concept with HVAC and fireplace industry partners as a potential disaster preparedness option.

Integrated Control of Heat Pump and Gas Fireplace Controls : Discussions are underway with the HVAC industry and utility partners to integrate heat pump and fireplace controls in the WSU Energy House. This would allow the thermostat to turn on either the fireplace or the heat pump's electric resistance heat strips when the heat pump cannot meet the home heating loads. This allows load shifting benefits for utilities and their customers during the winter peak and provides a good marketing strategy for HVAC manufacturers who sell both gas fireplaces and heat pumps to the manufactured housing industry.

Flexible Technologies: BAIHP partner Flexible Technologies developed an innovative system that improves the heat and tear resistance of the duct inner liner, reduces ductwork crimping without using sheet metal elbows, and improves the system-to-air seal where the crossover duct penetrates the bottom board. BAIHP and Flexible Technologies staff have been working with the region's manufacturers to promote the use of this new system.

Insider Heat Pump: Monitoring of the Insider heat pump at the WSU Energy House began in 2000. The measured flow rate of the indoor unit was good (850 CFM total, 425 CFM per ton), but BAIHP staff identified two performance issues: a too-frequent operation of the defrost cycle, and a lower than expected airflow at the outdoor coil. Continued testing of the Insider in 2001, indicated a 10% increase in coefficient of performance (COP) due to increased airflow at the outdoor coil. In 2002, WSU staff worked with FSEC to analyze performance data on the Insider heat pump.

At Vincent Village, the property manager indicated a high degree of satisfaction with the Insider heat pumps, with no comfort complaints since 1996. One Insider has been replaced and minor maintenance has been required to unclog some condensate drains.

Figure 17. Duct riser developed by BAIHP partner LaSalle.

La Salle Duct Riser: BAIHP staff worked with BAIHP partner La Salle Air to design and produce a duct riser for manufactured homes that uses mastic instead of tape. (Please see Figure 17.) BAIHP staff demonstrated prototype designs of the riser to Northwest manufacturers in 2002. Three manufacturers, Redman, Fleetwood, and Marlette, have adopted the new riser; and several others are considering it. BAIHP staff also have worked with Fleetwood's national office to promote the use of the riser in all Fleetwood plants.

In offering technical support to owners of over 100,000 homes built since 1990, staff answer questions from homeowners, manufacturers, retailers, and others. From late 2002 to mid-2003, staff from Washington, Oregon, and Idaho responded to over 70 phone calls and conducted 15 field visits. The number of problem home field visits has significantly decreased over the history of the program, due in large part to increased manufacturer and installer awareness of the SGC/NC/E-Star specifications. Also, Washington and Oregon now require manufactured home installer certification.

To support the certification process, BAIHP staff participates in quarterly meetings of the Washington State Manufactured Housing Technical Working Group. This group coordinates the certification of manufactured housing set-up crews. In 2001, 50 set-up crew received the training. During 2002, exactly 100 set-up crew personnel attended training and were certified.

A consistent field issue for manufactured homes continues to be excessive duct leakage, mostly because of butyl duct tape failure. (Please see Figures 18 and 19.) These findings were brought to the attention of the NFPA-501 Manufactured Housing Standards Committee, resulting in a successful proposal to revise the duct sealing specifications in the NFPA-501 Standard.

Figure 18. Riser disconnect	Figure 19. Riser disconnect close-up.

By early 2003, additional manufacturers eliminated the use of butyl tape for duct sealing, and began using mastic sealing instead. Fleetwood Homes of Washington, Marlette, Palm Harbor Homes, and Guerdon all adopted mastic. In-plant testing indicates significant improvement in the duct leakage rates of these homes. During the next reporting period, BAIHP staff will continue to test duct leakage rates both in the plant and in the field.

In 2000, staff in Idaho and Washington field-tested 49 SGC/NC homes built from 1997 to 1998. In 2001, analysis of field test data confirmed some improvements to home setup procedures and air leakage control, while highlighting a need to improve duct tightness and ventilation system operation (through homeowner education). In early 2002, BAIHP staff produced an updated homeowner ventilation brochure. Following this, BAIHP staff worked with Ecotope to develop a valid sample for the next round of field testing, and began to develop the test protocol. Currently, field testing is scheduled for the summer of 2003.

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