NEW YORK CITY

With co-op boards and condo associations constantly on the lookout for money savings and energy conservation — which often amount to the same thing — many boards are wondering if they should install a relatively new technology known as "tankless" water heaters. What are they, and do they really provide energy savings?

Tankless water heaters work by heating water with either a gas burner or an electric element, and delivering water as a constant supply. Heat loss is effectively avoided because of the instantaneous nature of the system. But here comes problem No. 1: The flow rate of hot water can decrease as demand increases.

Indeed, tankless water heaters — which are being marketed to smaller co-ops and condos in addition to their primary user, owners of single-family homes — seem at first glance to be a big plus: They are, on average, 24 to 34 percent more efficient than traditional heaters. They require less energy and last twice as long as their more conventional counterparts. They can also run on electricity, gas, propane, or solar power.

Some co-op / condo boards are dead set against allowing subletting / leasing (and for simplicity's sake, we'll just use the verb "sublet" going forward). One factor is the "transients" issue. Many contend that a renter doesn't care as much as an owner because he or she doesn't have as much invested (both financially and emotionally) in the property. But there are other issues as well that have to be considered when creating a policy.

Looking to lower the cost of electricity? Create your own! You've heard of co-ops, condos and other types of buildings and communities doing it via technologies like solar or wind power. But there's a lesser-known alternative: Cogeneration, also known as combined heat and power (CHP). It's a natural-gas-fueled method of generating electricity for the building and creating heat that can be used to power the air-conditioning system, heat the domestic water, and heat the building in winter.

Sewage backups, which can occur primarily in your co-op or condo's basement, pose health risks caused by contamination from harmful bacteria and mold. A blocked or broken sewer line is the obvious culprit. Here's what you need to know about your co-op's or your condo's sewer lines so that you can make an informed choice as to when and how to repair or replace them.

If your condo or co-op board is in a fog about FOG, then read on —  and save yourself some headaches down the road.

FOG is the acronym used by the city's Department of Environmental Protection (DEP) for describing the ingredients that are part of a common problem: fats, oil and grease. The difficulty arises when cooks deposit any (or all) of those in their kitchen drains: With more than 22,000 food service establishments serving over eight million New Yorkers, food remnants invariably get flushed into the sewers. Both restaurants and households discharge wastewater containing fats, oil, and grease into more than 7,400 miles of New York City public sewers.

"Real estate taxes have suddenly become the highest line item in a co-op's budget, and that being the case, boards should understand the [appeals] process," says attorney Eric Weiss, a tax specialist and partner at Tuchman Korngold Weiss Lippman & Gelles. "And they should be able to participate in the process if they feel that's important. I think it is important, from a budgetary standpoint."

It's not just a tax attorney saying that. Bob Friedrich, board president of the 110-building, 10,000-resident Glen Oaks Village co-op in Queens, agrees. "I think it's very important that all co-ops understand why they must appeal the valuations assessed against their properties," he says. This is also true of condo boards, which file appeals on behalf of the individually taxed apartment-owners, and for the condominium association's property taxes.

Many small co-op and condo buildings are hiring solely "back-office only" (BOO) services, performed either by a managing agent or an outside firm. The upside is that the building can get crucial financial work done and pay far less than it would pay for full management. The downside is that condo and co-op boards sometimes don't get what they expected or expected more than was promised.

Back-office services are typically the simple financial transactions required to keep a building afloat: collecting maintenance, paying bills and providing the board with a monthly record of the funds that come in and go out. Most BOO managing agents will perform additional services for a fee.

Condo and co-op board meetings should be productive, efficient gatherings where the board conducts business and doesn't meet to socialize. Are you getting the most out of your meetings? If not, consider a few of these things — from how to set an agenda to how you treat fellow board members and your managing agent.

The situation was both simple and complex. Simple, because the elderly woman had a dog — a clear violation of the co-op's rules. Complex, because her son told the co-op board that his mother had gotten the dog on doctor's orders. She was clinically depressed, you see, and the dog cheered her up. He said the board was in the wrong.

As it happened, the board in this case was anything but wrong — and its intervention may have helped save the woman, the dog and the co-op alike.

When you live in a co-op or condominium, the board of directors must regularly deal with owners who have a bone to pick about a neighbor's behavior. Whatever the complaint, the first question you and the co-op / condo board should ask yourselves is whether the issue is one that the board should be involved in at all. If an owner's behavior doesn't violate the governing documents or proprietary lease, then the board generally has no business butting in, no matter how loudly another owner complains. Some issues are merely neighbor-to-neighbor and not the board's concern.