The Causes for Odors in Your Ductwork: When to Call a Professional

Animal Odors

Although it may be a disgusting thought, bear in mind that many of the odors coming up through your registers will likely be animal related. These may be due to “animal smells” getting lodged in the filters, thereby sending the odor throughout the home through the ductwork. It could also be due to a mouse or rat that has died either in the ductwork itself or inside a building cavity. Thus, if replacing the filter doesn’t work, you may opt to call a professional who can locate the source of the stench and remove it.

Combustion Flue Gases

Combustion flue gases are dangerous and are loaded with carbon monoxide, so if you smell things that seem out of place – i.e. a “burning” scent, LP gas or oil, or anything else that you shouldn’t notice – it is crucial to contact someone right away, particularly if you do not have carbon monoxide detectors in your home. The release of flue gases into the ductwork can be caused by any number of things, but it is most commonly caused by a hole in the heat exchanger that allows the gases to seep into the ducts.

Mold Odors

Mold odors are also incredibly common in ductwork, but they can also be dangerous. Mold can have a severe impact on your overall health and cause persistent allergy symptoms, infections, and even permanent damage to your body. If you notice a mildew smell emanating from your vents, then it is best to contact a professional who can not only locate the source of the mold, but figure out how it got there in the first place. It is best to have it removed as soon as possible.

Septic or Sewer Odors

Another common odor that homeowners report, primarily in the winter season on days or nights when the furnace is used, is a sewer smell. There are a number of causes for this, but it might be that a sewer line has cracked or is leaking onto ductwork. Thus, when the furnace is running and air is coming from registers, it is bringing that rather strong sewer smell with it. It may also occur when the condensate drain is connected to the sewer without a trap. In this case, sewer gas may leak up through the condensate drain and into the furnace. A professional plumber can install a trap in the condensate line to alleviate this problem.

Remember that if you are smelling mold, flue gases (or the odor of combustion byproducts), or sewer odors in your home, it is important to have these issues addressed immediately as they present serious hazards to your health and perhaps even the risk of explosion in the case of methane (sewer) gas in high concentrations.

Strange and unpleasant odors in your ductwork can be frustrating or even embarrassing when you have friends and family in your home. If you’ve noticed some unusual smells emanating from your registers and you’d like to take care of them in time for the holidays, you’ve come to the right place. Though some of the odors might be considered benign and simply annoying, others have the potential to be dangerous. You may need to clean, repair, or replace parts of your ductwork to solve the problem.



The Difference Between Old and New Furnaces

old-vs-new-street-signs-300x300There have been many advances in the heating and cooling industry over the past couple decades alone. And when homeowners hear about some of these changes, they sometimes ask, “Do new furnaces work differently than old furnaces?” This is a great question that depends on the age and style of your current furnace. Today we’re going to talk about some of the major differences between old and new furnaces so that you know what to expect when replacing your old system!

New furnaces vs. old furnaces: General differences

Furnaces today are able to heat your home much more evenly and efficiently than older furnaces. One way that they have been able to achieve these improvements is by blowing more air over the heat exchanger. If you’re upgrading from an old furnace to a new furnace, this might mean that you hear more noise from your air handler. However, there are ways to minimize this noise (as you’ll see below).

In addition, some older furnaces use expensive energy sources like electricity to heat your home. Unless you’re installing a heat pump, gas is the most efficient and least expensive energy source for heating your home, and that change could be a big difference between your old and new systems.

New furnaces vs. old furnaces: New heating technology that’s available

Although furnaces still operate in generally the same way as they used to, there have been many new technologies that have emerged that allow heating systems to operate more efficiently and effectively. One example of this is a variable speed air handler. Unlike older air handlers, which only operate at a single speed, variable speed air handlers operate at multiple speeds depending on airflow requirements at any given time. This not only helps save energy, but also allows your system to operate more quietly.

Another example of new furnace technology is dual stage heating. Unlike older furnaces that can only operate at full capacity, furnaces with dual stage heating have a high and a low setting. The low setting is used about 75 percent of the time, which saves a whole lot of energy, and the high setting only kicks on when it’s extremely cold outside.

New furnaces vs. old furnaces: Possible differences in venting

Another big difference that you might notice between your old and new furnace is how it vents combustion gases. Older furnaces always vented their gases out of a vertical vent that extended out of the roof. The highest efficiency furnaces available today use more heat out of the gas that they consume. As a result, they have a different venting process which uses PVC pipes that lead out the side of your home.

If you have any questions about the difference between new furnaces and old furnaces, or if you’d like a heating and cooling system serviced or installed in your home, contact Cottam Heating, your New York heating and air conditioning contractor. We service Manhattan, Westchester and Lower CT.

New York: Are you ready for Fall?

thumbs-up-repair-guyFall is finally here, and winter (& possibly tons of snow) is right around the corner.  This past week on our Facebook page, we’ve posted a new tip everyday to help you prepare your home for the winter weather.  To make them easier to follow, I have posted this blog article so they will be in one, convenient spot for you.

Tip #1 – Have a programmable thermostat installed! It automatically controls the heat when you are away or at home, so you can cut down your energy use when you don’t need the heat.

Tip #2 – Is your house drafty? If so, you may need to seal air leaks and install additional insulation. Lucky for you, Glenmont has an energy auditor who can assess your house, and suggest improvements.

Tip #3 – Repair cracks in windows, caulk and weather strip leaky frames. Installing weather stripping helps keep cold air out of your home. If your window frames have gaps, cold air is leaking into your house. An energy audit can find these problems for you.

Tip #4 – Use drapes where your windows face the sun. Keeping them open during the day will allow the sun to naturally heat your home, and closing them in the evening will reduce the cold drafts at night. This will also keep your heating system from constantly working!

And your last tip – Tip #5 – Have a professional check your heating system! A simple maintenance to make sure everything is clean and working properly can save you up to 10% on your heating costs.

Hopefully, these tips will help you save money on your energy bills.

Don’t forget to call Cottam Heating & Air Conditioning to schedule your heating maintenance! (800) 734-8367

4 Common Misunderstandings about your HVAC System

misunderstandingProblem #1: Homeowners let the heat load get too high

When homeowners leave the home for more than three to four hours at a time during peak heat periods, they oftentimes close their windows and doors which will result in no home ventilation. While they’re out, the indoor home temperature rises considerably. For example, it can be 95 degrees outside and by the time you arrive home the indoor temperature has risen to 88 degrees.

This is an uncomfortable temperature for most families so turning on the air conditioner is the logical solution, usually set in between 73 to 75 degrees. Unfortunately, even if the air conditioning never turns off, it may take hours to lower indoor room temperature (as a whole) from 88 degrees to 75 degrees.

When the home gets too hot and the AC has to work overtime, it:

  • Stresses out the air conditioning system, adding strain
  • Expends extra energy
  • Costs more to cool the home now and maintain later


When you know you’ll be out of the house during peak heat hours, leave the air conditioner on to a reasonable temperature (78 to 80 degrees). That way, when you return home you can adjust the thermostat to a comfortable 75 without stressing out your air conditioner.

Problem #2: A lower number on the thermostat does not mean cooler air

Each central air system works to cool air by 15 to 20 degrees at a time. As an example, if the indoor air temperature is at 80 degrees, the AC system takes that supply of air and subtracts 15 to 20 degrees of heat before releasing it back into the home air supply. Because it mixes with the other 80 degree air that has not been conditioned yet, the air you feel will be cooler but not necessarily the temperature that you set on your thermostat. It takes time for the indoor air to reach temperature equilibrium.

However, if you detect the mixing of conditioned air and the indoor air supply is not the reason for poorly conditioned air there may be a greater issue. Though air is still conditioned, it is less efficient, working twice as hard to cool the same amount of air.


If your air is not cooling air in 15 to 20 degree increments, a maintenance call is required to restore proper function and efficiency levels.

Problem #3: Homeowners ignore filter maintenance

A good maintenance call scheduled regularly eliminates issues with poor or dirty filtration. From stuffed filters to build-up over the evaporator coils, keeping your central air system clean not only benefits the system itself but the sanitation of the air you breathe inside of your home.

When air filters are not replaced or cleaned out it adds strain upon the AC because it is now more restrictive than before. This means less air gets through the filter and less air is conditioned. If this happens, it also causes the evaporator coils to ice up while the system overheats.

The evaporator coils are hollow tubes through which refrigerant flows. Once the refrigerant reaches the evaporator coils, the coils grow cold so that the indoor air supply that passes over them are cooled before returning into your home. Something as simple as a dirty filter can stop this process because less room temperature air passes over the coils which in turn ice up.

Likewise, poor air flow due to dirty filters encourages the system to overheat and shut down. This is because a central air system needs a heat source to function and restricted air flow means the same amount of energy is used for less and less air.

Filters that are not serviced are the number one reason to system shut-downs.


Have your preferred HVAC technician visit to service your AC system. Be sure to replace filters and have the evaporator coils and drip pans cleaned. These areas collect water and are prone to microbiological growth.

Problem #4: The AC system is not an open system

Homeowners, new and old, have a tendency to think that their air conditioning system is an open system. This is not the case. Contrary to popular belief, there is no need to refill your refrigerant supply.

Given that your AC system was installed properly and there are no leaks that have accumulated during its lifespan, the same supply of refrigerant is recycled each and every single day.

However, if your refrigerant supply does experience a leak, it requires the attention of a HVAC technician as soon as possible. Refrigerant is a gas that damages the ozone layer if released into the atmosphere. Your technician can repair the leak and restore its proper supply.

When your refrigerant supply does drop due to a leak, the system is less efficient because it has less cooling power to work with. If your AC system previously cooled indoor air in 20 degree increments, it now may be cooling in 10 degree increments; the air conditioner works harder to condition the same amount of air.


Have your preferred HVAC technician repair the leak, refill refrigerant and recalibrate.

Cottam Heating and Air Conditioning is the leading heating and cooling company in City Island, New York City and Westchester.  If you have any questions about cracked heat exchanger detection of if you’d like a heating system or installed in your home, contact Cottam!  Give us a call at (718) 885-3328. You can also check us out on Facebook or Twitter. We service City Island, Manhattan and Westchester counties! 


Hot weather is not only uncomfortable, it’s bad for your health.

Fortunately, you can maximize comfort and save on cooling costs during even the hottest weather by developing wise habits. Start with these nine tips to keep cool:

1. Clean Your Cooling System

Before the hot weather starts, you should make sure your cooling system is clean and well-maintained. A professional should inspect it every year.

If the system is over 15 years old, you might consider replacing it with a newer model, preferably one with an ENERGY STAR rating.

2. Check for Air Leaks

Check your home for air leaks. The better sealed the house, the less it loses cool air or is infiltrated by warm air. You should check for gaps in caulking around the house, and reseal where necessary. Also check the weather-stripping on your doors and windows to make sure they’re airtight.

3. Seal Ductwork 

You should also have a professional repair and seal any leaky ductwork. Air loss through ducts accounts for about 30 percent of a cooling system’s energy consumption.

Where forced air cooling systems are in use, it’s important to ensure that the filters are changed regularly to help optimize energy efficiency.

4. Open Windows

Controlling air flow is a cost-effective way to moderate temperatures. If nights are cool, you can turn off their air conditioner and open your windows and balconies to lower indoor temperatures. During the day, you can shut doors and windows to trap cool air inside.

5. Shut Blinds

As the sun rises higher during the day, you can draw your curtains and shut your blinds to keep the sunshine out. This can reduce heat gain by 45 percent. You could consider installing exterior window coverings to keep out the sunshine. Air conditioning vents should be kept clear of blockages caused by drapes or furniture.

6. Cook Outdoors

Another tip is to minimize running appliances and equipment that generate a lot of heat, like stoves, computers, dishwashers, curling irons or hair dryers. Barbecuing is a tasty alternative to running your stove.

7. Install Ceiling Fans

Ceiling fans allow you to set thermostats about 4° F higher with no reduction in comfort.

8. Use Programmable Thermostats

Programmable thermostats can automatically turn down the air conditioning at night or when the home is not occupied, saving energy and money when lower temperatures are unnecessary.

9. Invest in Zoned Cooling

A ductless cooling system with zoned control is a good investment to consider. Zoned control allows you to set the temperature of each room individually rather than having to keep the entire house at the same level.

Keeping cool in hot weather is not complicated. It just needs good home maintenance, common sense and a well-functioning cooling system.

{This article originally appeared on}

Cottam Heating and Air Conditioning is the leading heating and cooling company in City Island, New York City and Westchester.  If you have any questions about cracked heat exchanger detection of if you’d like a heating system or installed in your home, contact Cottam!  Give us a call at (718) 885-3328. You can also check us out on Facebook or Twitter. We service City Island, Manhattan and Westchester counties! 

Control those high summer energy bills!


Summer is fast approaching and in New York, it can get pretty hot. Some homeowners dread summertime because of the need to constantly run their cooling system. Below you will find some tips to help control your summer cooling costs and keep your hard earned money in your pocket.

Skip using appliances that produce heat until the sun goes down.The added heat from the stove or dryer will make it hotter in your home causing you to feel the need to lower the AC temperature. When you take a shower, use the exhaust fan to pull the steam from the bathroom. When you reduce humidity, you increase comfort.

Change the AC filter on a regular basis. A unit with a clean filter will run far more efficiently than one with a dirty filter. Keeping the filter clean and free of dust and debris will allow for good air movement within the system.

Invest in a programmable thermostat. A programmable thermostat allows you to adjust the temperature according to your schedule. Try keeping the temperature set at 78 when you are home and raise it when you are away. Raising the thermostat temperature when cooling is not needed can reduce your energy bull by up to 15 percent.

Regular maintenance pays off. Make sure you stay up to date with the maintenance requirements of your HVAC unit. Keep the outside unit clean and free of leaves and other yard debris to avoid damage to the system.

Use the ceiling fan. Fans circulating the air in your home can make you feel much cooler. Fans don’t necessarily lower the temperature in the room but they do make it more comfortable. Make sure you remember to turn the fan off when no one is using the room to save energy costs.

Close the curtains. When you allow sunlight into your home, it is going to get hotter. Consider replacing your curtains with solar curtains that are made to block out sunlight.

Consider the age of your unit. If it is more than 15 years old, you should think about replacing it with a more energy efficient unit.

If you put these tips to use, you are sure to see a significant decrease in your energy bill this summer.

Cottam Heating and Air Conditioning is the leading heating and cooling company in City Island, New York City and Westchester.  If you have any questions about cracked heat exchanger detection of if you’d like a heating system or installed in your home, contact Cottam!  Give us a call at (718) 885-3328. You can also check us out on Facebook or Twitter. We service City Island, Manhattan and Westchester counties! 

The Cost of Neglecting Your Home Comfort System


Looking at cost is more than seeing a price tag.  Take the annual maintenance for your heating equipment.  If you apply a small percentage of the value of the equipment in routine annual maintenance, your investment reduces your energy expenses, saves on repairs and takes care of you longer.

That’s a pretty sweet deal.

However, if you neglect to routinely take care of your furnace, you incur issues both seen and unseen that can cause breakdowns, waste energy and develop potentially dangerous problems for you and your family.  Here are just a few areas where neglect can prove so costly.

Energy use increases.  When dirt clogs your system, it has to work harder to keep you warm.  Less efficiency means higher operating costs.  In fact, energy experts say that your energy costs can be reduced by 30 to 35 percent when heating equipment is serviced regularly and properly maintained.

Equipment life is shortened. With all that dirt and grime causing efficiency problems, your system is running longer and more often.  Thus, the parts feel the pressure, and they’ll wear out sooner.  Even a small problem that goes undetected for a long period of time can lead to an earlier than normal system failure – or cause breakdowns with big repair bills.

Preserving your manufacturer’s warranty.  Heating and cooling systems are big-ticket home improvements that come with long-term warranties.  But many of these warranties require routine maintenance to keep them in effect.  Don’t risk losing your warranty due to neglect.

Protecting your family’s safety. This may be the last “cost” in this list, but certainly ranks highest in what matters most.  An unmaintained system can put you at risk of a deadly carbon monoxide leak.  Loose electrical connections in an unmaintained system can also create a fire hazard.  Neither are worth the risk of neglecting routine maintenance.

If you’d like to schedule a maintenance, we’d be honored to have you trust your system to us.  Let us hear from you.

Cottam Heating and Air Conditioning is the leading heating and cooling company in City Island, New York City and Westchester.  If you have any questions about cracked heat exchanger detection of if you’d like a heating system or installed in your home, contact Cottam!  Give us a call at (718) 885-3328. You can also check us out on Facebook or Twitter. We service City Island, Manhattan and Westchester counties! 

Shopping for a New Furnace? Here Are Some Helpful Tips


Replacing your older furnace with a newer and more efficient model can lower the cost of keeping your home warm. A newer furnace produces less pollution and provides heat more consistently than older models. However, there are certain factors you should consider when shopping for a new furnace. Keep the following in mind:


The efficiency of a furnace is rated in terms of its annual fuel utilization efficiency (AFUE) rating. The more efficient a furnace is, the more expensive it will be to operate in most cases. A furnace with 90 percent AFUE may go for $1,000 more than a unit with a 10 percent lower AFUE rating. However, you’ll be able to recover the cost via lower utility bills over the course of the unit’s life.

Note that while electric furnaces are more efficient than gas ones, electricity is often a more expensive fuel than gas. This means that an electric furnace may still be more expensive to run.


It’s extremely important that you select the right-sized furnace. An undersized furnace will not be able to keep your home sufficiently warm when the weather outside is very cold. On the other hand, an oversized furnace will cycle on and off too frequently, which can cause parts to wear out more quickly.

Reliability and Servicing

No matter which brand you choose, you’ll need to maintain your unit to ensure that it functions properly over the long-term. This includes regularly changing filters and having it inspected by an HVAC technician.

If you’re shopping for a new furnace, contact Cottam Heating & Air Conditioning. We have been providing quality HVAC services to the Manhattan and Westchester areas for over 20 years. Our HVAC experts will be able to provide the advice you need to make a good decision.

Cottam Heating and Air Conditioning is the leading heating and cooling company in City Island, New York City and Westchester.  If you have any questions about cracked heat exchanger detection of if you’d like a heating system or installed in your home, contact Cottam!  Give us a call at (718) 885-3328. You can also check us out on Facebook or Twitter. We service City Island, Manhattan and Westchester counties!