Air Conditioner Proposal

Buildings 2003-08-06

Summary:

GO member households may install central air conditioning systems. These systems must be properly sized and placed according to the guidelines below, used with sensitivity around noise to the community. Window AC units are not allowed.

Background:

A critical piece of Great Oak's vision statement concerns sustainability, and the first concrete application of this ideal has been in the design of our homes. Our stated goal of energy-efficient homes was addressed first with good design and then with solid construction techniques, with careful attention paid to insulation (walls, windows, basements and roofs), and to ventilation (gable vents, potential for attic and ceiling fans, and windows designed to provide cross-flow). Our overall energy costs should be relatively low, and special attention was given to creating homes that use passive cooling instead of mechanical air-conditioning requiring refrigerant (Freon or Puron), compressors, and condensers. Nevertheless, there are households which want or need mechanical air conditioning, with its provisions for air cleaners and humidifiers.

We are all aware of the potential negative impact of mechanical air conditioners on the community that need to be addressed. Foremost is noise: AC units need to be vented to the outside, and there is inevitably noise created by the fans and compressors. In some cases, the noise is heard more easily by the neighbors than the household with the AC, as anyone who has lived in a big apartment complex can attest. Other issues include waste heat and aesthetic and practical issues around placement of the compressor.

Since this proposal was first introduced, some homes have already had AC installed by Phoenix, with an AC unit Robertson-Morrison believed would be acceptable to the community in terms of noise (the SEER 12 Bryant 552). This had the advantage of allowing us to listen to several real live Bryant 552s on site (units 8 and 17).

This proposal seeks to formalize our unspoken agreement to permit central air conditioning in Great Oak, and to specify the criteria for acceptable AC makes/models, as well as placement.

Facts
* SEER (Seasonal Energy Efficiency Ratio) ratings are a measure of an AC unit's energy efficiency over the cooling season. It represents the total cooling of a central air conditioner or heat pump (in Btu) during the normal cooling season compared to the total electric energy input (in watt-hours) consumed during the same period. SEERs are based on tests performed in accordance with DOE test procedures (found in 10 CFR 430 Appendix M subpart B).

* A Consumer Reports survey (taken in 2000) indicated that many AC contractors believe that high- and low-efficiency AC systems are more prone to problems than mid-efficiency models (with a SEER of 11-14). In addition, several local AC installers stated that for Michigan summers anything above a SEER of 12 is "overkill."

* Best places to install a compressor: north side or any area shaded from direct sun. This works well for walkout-side units, less well for others.

* There are various ways of reducing the noise impact of AC systems, including:
o standard methods of noise reduction such as baffles and plantings;
o limiting the hours during which the compressor runs;
o adjusting the thermostat so that the compressor runs less.

Proposal:

1. GO member households are encouraged to employ passive cooling (closing windows and drawing blinds during daylight hours, using the whole house fan and opening windows in the evening, using additional floor or desk fans as needed) for at least the first year to see how it goes.

2. GO member households may install central air conditioning systems. These systems must be properly sized and placed according to the guidelines below, used with sensitivity to the community, and properly maintained. Installation and maintenance are the responsibility of the member household, not of GO.

3. Window AC units are not currently allowed. If technology improves to the point that a window AC can meet the noise requirement of not impinging on its neighbors, this prohibition may be lifted. If local cooling is needed and a household doesn't wish to install central AC, internal AC systems such as a Pinguino should be considered.

4. The system you install must be the one currently recommended by the ARC, unless there is a compelling reason to do otherwise. (The exact make and model will change as technology and the market evolve.) The current standard system is the Bryant 552, with a SEER of 12. If you think you have a compelling reason to install another system, you must submit your alternate AC system to the ARC so that it can go through the ARC review process.

5. If a GO member household follows these guidelines carefully, and other households nevertheless complain that your A C unit is "too noisy," it is the member household's responsibility to take remedial action. However, since noise is somewhat subjective, and the possible problems so varied, it's difficult to provide strict guidelines. As with other aspects of living in community, we expect community members to make a good-faith effort to keep their neighbors happy, and invite them to make use of our conflict resolution process.

Pros
* Individuals who want AC can have it.

* Noise is minimized.

* Compressor units are positioned on the periphery of the community, in backyards.

* A process is defined for handling noise issues.

Cons
* Central AC systems have the effect of driving people inside in the summer instead of out into the community.

* Efficiency rating is not a guarantee of low noise, making it hard to choose alternative models to the Bryant 552 without listening to them (more of an issue in future years when replacement becomes an issue).

* Even low-noise units still may intrude into adjacent units when ambient noise is low (e.g., at night).

* Some units may not be able to be positioned on the periphery, thus intruding into community space.

* Compressors are large and ugly.

* Individual unit owners may be required to "fix" a noise problem when they have met all other requirements. What counts as a problem is somewhat subjective.

Process Comments:

0 stand asides.