Frequently Asked Questions

Heating FAQ

• What is an A.F.U.E. (Annual Fuel Utilization Efficiency) rating and what do they mean to you?
• What is a Modulating or Two-stage furnace?
• Do I need to get my furnace cleaned every year?
• How often should I change the standard throw-away 1" filter on my furnace?
• How can I make sure that my HVAC system is safe for operation?
• If I go away for a few days or even longer during the winter, at what temperature should I set my thermostat?
• My thermostat is equipped with two position settings for the fan, “automatic” and “on”. Where should I set it?
• I have trouble getting even amounts of heat/cooling to certain parts of my house. How can I get more heat/cooling to the upstairs/downstairs of my home?
• Does it pay to turn down the thermostat at night or when you leave your home for any length of time during the day?
  
  

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What is an A.F.U.E. (Annual Fuel Utilization Efficiency) rating and what do they mean to you?

The efficiency of a furnace is measured in a rating known as A.F.U.E. (Annual Fuel Utilization Efficiency). A lot like your car’s miles per gallon rating, A.F.U.E. tells you how efficiently the furnace converts fuel (gas, oil or propane) into heat. An A.F.U.E. of 80% means that 80% of the fuel is used to heat your home, while the other 20% basically goes up the chimney.

In 1992, the government mandated a minimum A.F.U.E. rating of 78% for furnaces installed in new homes. (In contrast, many furnaces manufactured before 1992 had A.F.U.E. ratings as low as 60% - so nearly half the fuel was being wasted.) Furnaces with A.F.U.E. ratings of 78% to 80% are considered “mid-efficiency”, while those with ratings of 90% or higher are termed “high efficiency”.

In general, a higher efficiency furnace usually means two things.

* lower monthly operating costs
* higher comfort levels

If you have an older furnace (10 – 15 years old with an estimated A.F.U.E. of around 60%), you could save up to 40% on your heating bills by replacing it with a new high-efficiency furnace. So the cost to replace your older, inefficient furnace is paid back through lower utility bills. Back to the top.

What is a Modulating or Two-stage furnace?

Modulating Furnace: Most furnaces are either “off”, providing no heat, or “on” at full capacity, with the burner and blower operating at 100%. This causes the temperature in your house to go up and down by several degrees – affecting both your comfort and your energy bills. Furnaces are designed to keep your home warm on the coldest of days. But in most cases, those days account for only 2-1/2 percent of the heating season. The rest of the time, you furnace is providing more heat than is needed to satisfy your comfort requirements. Modulating furnaces solve this problem by “modulating” between different capacities (40-100%), depending upon the comfort requirements of the homeowner and the temperature outside. This results in lower operating costs, quieter operation and much more even temperatures throughout the home. It’s like having a separate furnace to handle the unique heating requirements of each day – all in one unit! Check out the Rheem Modulating Furnace with Contour Comfort Control – the only truly modulating gas furnace in the world!

Two Stage Furnace: A two-stage furnace has the same concept in mind as a modulating furnace. The difference lies in the fact that while a modulating furnace can operate at any capacity between 40% and 100%, a two-stage furnace operates on a low-stage and a high-stage. The low and high stages have preset BTU outputs. On most days, the furnace will operate at its first stage to only provide the heat you need to stay comfortable. On those very coldest days of the year, this furnace will ramp up to its second stage and give the full BTU output of the furnace to keep satisfying the heating requirements of the home. It’s basically like having two furnaces in one – one for warmer days and one for the very coldest. Back to the top.

Do I need to get my furnace cleaned every year?
Naturally, you would expect a heating contractor to recommend an annual furnace cleaning as we do. But we do so for a number of reasons. A cleaning means that your furnace will operate more efficiently, getting more heat for your fuel dollar. More importantly, however, the cleaning also includes a thorough safety check of the entire unit for cracked or defective/damaged parts. This annual maintenance check will assure you a carbon monoxide free winter. An annual cleaning is also recommended by all manufacturers as well as utilities. Back to the top.

How often should I change the standard throw-away 1" filter on my furnace?
You should change your standard 1” filter every 6-8 weeks. Believe it or not, a filter actually becomes more efficient as it gets dirtier – up to a point. After peak efficiency is reached, the efficiency drops again. Make sure to inspect the filter and use your own judgment. Don’t let the filter get “clogged” as this can cut down on the efficiency and/or cause damage to the unit. Back to the top.

How can I make sure that my HVAC system is safe for operation?
Always have your system checked annually to make sure that the unit is safe. In many cases, tiny cracks or perforations in the heat exchanger occur. If you furnace is burning inefficiently or incompletely, carbon monoxide can escape and fill the house causing serious health problems and/or death to those inside. Back to the top.

If I go away for a few days or even longer during the winter, at what temperature should I set my thermostat?
We recommend 55 degrees. It’s low enough to save you energy and money but warm enough to protect your pipes and other vital parts of your structure. Also, it’s a good idea to turn your main water supply off even if you’re only going to be gone for a day. A water leak could cause serious and very costly damage to your home. Back to the top.

My thermostat is equipped with two position settings for the fan, “automatic” and “on”. Where should I set it?
The two positions are usually used in conjunction with a central air cleaning system. The normal setting is on “automatic” and the fan’s cycle will be controlled by the temperature in the room. However, if your home is equipped with an air cleaner (media or electronic) or you wish to keep a continuous flow of air, switch the setting to “on”. Remember, central air cleaning devices only work when the furnace is circulating air. If you wish to get the most from your air cleaner, you should keep the setting to “on”. Back to the top.

I have trouble getting even amounts of heat/cooling to certain parts of my house. How can I get more heat/cooling to the upstairs/downstairs of my home?
Adjust the louvers inside the registers on the wall or floor in the room where too much heat/cooling is present so that the registers are partially closed. For example, to get more cooling upstairs during hot summer months, partially or fully close the registers downstairs to force more airflow to the upstairs registers.

Another possible solution is a furnace equipped with a variable speed blower motor. These furnaces are designed to overcome airflow problems in a home and will keep the airflow steady all over the home. These types of furnaces also use about 1/3 the electricity of a standard furnace and can save considerable amounts of money in operating costs.

A zoning system is also a possible solution to this problem. Zoning is the controlled delivery of heated or cooled air to a particular area of the home, without heating and cooling the entire home. Temperatures can be set and maintained independently throughout the home through the use of multiple thermostats. Back to the top.

Does it pay to turn down the thermostat at night or when you leave your home for any length of time during the day?
Yes, there would be some fuel savings but we do not recommend lowering your thermostat by more than 5-7 degrees. You might think about the purchase of a programmable thermostat. It would do the job for you automatically. Back to the top.

Air Conditioning FAQ

• What is a S.E.E.R. (Seasonal Energy Efficiency Ratio) rating and what does it mean to you?
• Why does a higher efficiency rating (SEER) save energy?
• How does an air conditioning system actually work to cool the air in my home?
• How do I know what size unit our house needs?
• If an outdoor unit needs replacing, should the indoor unit be replaced too?
• Can shrubs or flowers be planted around an outdoor unit?
• Can I turn off the power to my central air conditioning system during the cold winter months?
  
  

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What is a S.E.E.R. (Seasonal Energy Efficiency Ratio) rating and what does it mean to you?
S.E.E.R. stands for Seasonal Energy Efficiency Ratio, the standard measurement of air conditioning efficiency established by the U.S. Department of Energy. What does this mean to you? Higher S.E.E.R. ratings translate into greater energy efficiency which means lower summer cooling bills. The most important thing to remember is the higher S.E.E.R. rating, the more money you save. Back to the top.

Why does a higher efficiency rating (SEER) save energy?
If your current air conditioner or heat pump is more than 10 years old, it could be operating at lower than 8.00 SEER. Compare the estimated annual bill of an 8.0 SEER system to that of a higher SEER, such as a 12.0 or 13.0. For instance, if the annual cooling bill of an 8.0 SEER system in a particular area is $1,000, it could cost only $615 for a 13.0 SEER system to operate at the same capacity in the same area. This is an annual savings of 38%. Now that makes sense, doesn’t it? Back to the top.

How does an air conditioning system actually work to cool the air in my home?
An air conditioning system consists of 2 parts: an outdoor unit (where liquid refrigerant is contained) and an indoor coil (where the refrigerant is pumped into). As the air moves across the air conditioning coil (usually located on top of the furnace), the refrigerant removes the heat from the air as well as the moisture by condensing it on the cold surface of the coil. In this way, an air conditioner not only cools but also dehumidifies the air. Virtually any system can have air conditioning hooked up to it provided that it is a forced air system. In cases where there is not forced air heating or a duct system, we can use “ductless” air conditioning systems to cool an entire home or small business. Back to the top.

How do I know what size unit our house needs?
Ask your Rheem Team dealer. He will consider many factors before making a recommendation. Factors like… size of the house, climate, the number and type of windows installed, insulation, and even the number of people living in the house. Back to the top.

If an outdoor unit needs replacing, should the indoor unit be replaced too?
Yes. Rheem air conditioning and heating systems are designed to operate as a complete, matched system. The efficiency rating is based on the entire system. Replacing the entire system ensures the system will be reliable and efficient. Back to the top.

Can shrubs or flowers be planted around an outdoor unit?
Yes. However, we recommend that plants be no closer than 18 inches from the unit. This allows for plenty of room for air circulation in and out of the unit. Without this room for air circulation, the unit could overheat, resulting in a premature need for service. Back to the top.

Can I turn off the power to my central air conditioning system during the cold winter months?
Yes, you can. There is a disconnect in your panel box or at the outside unit. Turn it off over the winter and save energy. But when you turn it on again in the spring, do it at least 24 hours before turning on the cooling equipment. A day’s delay will give the oil time to warm and lubricate the essential parts upon startup. Back to the top.

 

Water Heaters FAQ

• I am looking at purchasing a new water heater. What does the energy factor mean?
• I need to purchase a new water heater. Are they all the same?
• How can I do an emergency shut down of my gas water heater?
• Why is my water heater making noises from within the unit?
• How do I drain my residential water heater?
  
  

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I am looking at purchasing a new water heater. What does the energy factor mean?
Energy Factor is a relative number that is a standard measure for storage water heating products. It is determined through a Department of Energy (DOE) standard test procedure. This procedure involves a water heater that is put through a 24 hour simulated test.

The same DOE simulated use test is used by all water heater manufacturers. All of the test procedures are mandated by the DOE. Test procedures include the length of the test, the thermostat setting, the water temperature of the cold water delivered into the water heater, and the quantity of hot water drawn from the heater during the 24 hours of testing.

The final number is displayed in a decimal equivalent. It is not meant to be a percentage. This number, call the Energy Factor (EF) represents the efficiency of the water heater. The higher the EF, the more efficient the unit. Back to the top.

I need to purchase a new water heater. Are they all the same?
Whether you use gas or electricity the most important feature of a water heater is energy efficiency. Some of our water heaters can save you hundreds of dollars over the life of the product. For example, our professional grade water heater is more energy efficient and provides more hot water in less time than a typical water heater. A professional installer can help you select the right model for your home. Back to the top.

How can I do an emergency shut down of my gas water heater?
Should overheating occur or the gas supply fails to shut off, turn off the manual gas control valve to the appliance. If the water heater has been subjected to fire, floor or physical damage, turn off the manual gas control (shut-off) valve, and do not operate the water heater again until it has been checked by qualified personnel. Back to the top.

Why is my water heater making noises from within the unit?

Rumbling and Pounding
Rumbling, pounding and other noises when the heater is in operation are usually caused by formation of scale and sediment. Minerals will form a scale on the bottom of the inner tank that traps minute amounts of moisture. Heat from the gas burner changes these tiny trapped amounts of moisture to steam and the pressures developed cause the rumbling and pounding noises. In addition to being very annoying to the homeowner, accumulation of sediment and mineral deposits in the bottom of the tank can appreciably shorten the tank life of the heater. Back to the top.

The sediment can interfere with the transfer of heat from the flame through the tank wall to the water. The sediment acts as an ‘insulation’ restricting heat transfer and may contribute to a ‘not enough hot water’ trouble call. If a homeowner does not periodically drain and flush the tank, the sediment will build up – eventually to the point it may cover the immersed thermostat bulb. Diagnosed early, these sediments may be flushed out simply be periodically draining the tank. Back to the top.

Sizzling
Another noise associated with a gas water heater is a sizzling or pinging noise. Condensation is the most likely cause of this annoying problem. Condensation forms on the side of the tank and flue ways when it is first filled with cold water, during heavy hot water usage periods or when the cold water inlet temperature drops as the seasons change. Drops of water falling on the burner can produce a sizzling or pinging sound and may be seen by opening the jacket door and looking at the burner assembly. The condensation is not unusual and will disappear after the water in the heater becomes hot. If the problem persists, check connections and the tank for signs of leaking. Back to the top.

Banging Baffles
Inside the middle of the water heater is a flue, a device that carries the combustion air products and discharges them, through the venting system, to an outside atmosphere. The flue also aids in heating the water by transferring heat through the flue tube to the water. Inside the flue tube is a device that retards air movement through the flue called a baffle. The flue baffle is a metal device used to keep the heating combustion gases in the flue longer for maximum heat dispersion to the tank water. The baffle is an engineer designed component of the heater and is essential to the heater’s efficiency rating. On occasion, the baffle will make a noise like banging metal to metal. This is exactly what is happening. The baffle is ‘wiggling’ round the hander bracket and making noise by banging against the side of the flue tube. This is a normal noise and can be removed by bending the metal tabs on the hanger bracket to tighten the baffle. Another method is to remove the baffle and bend it slightly; then reinstall the baffle. The idea is to make a snug fit back into the flue tube. Back to the top.

How do I drain my residential water heater?
CAUTION: Flushing your water heater may put you at risk of being scaled by hot water. Please be careful when working on your water heater. The water will be hot…be sure no one is near the drain hose or they could get scalded.

1. Turn to power OFF the water heater at the circuit breaker (electric heater) or main gas line (gas heater).
2. Fasten a length of garden hose to the drain valve at the bottom of the heater. Put the other end of the garden hose in the nearest floor drain or snake it outside the home.
3. Close the shut off valve at the cold water inlet line.
4. Open the temperature and pressure relief valve at the top of the heater. Now open the drain valve and allow the water to drain. You will probably notice some small white particles (called scale or sediment) during the early stages of the flow.
5. When the water stops, close the drain valve and remove the hose. Also close the temperature and pressure relief valve at the top of the heater.
6. Open a hot water faucet somewhere in the home. Open the shut off valve at the cold water inlet line. You will hear the heater start to fill.
7. When you have a steady stream of water from the open faucet, turn the faucet off.
8. Turn the power ON to the water heater at the circuit breaker (electric heater) or main gas line (gas heater). Allow the water heater to recover. Check the drain valve one more time to make sure it is tight.

Homeowners should flush their water heaters at least every six months. Some areas of the country with hard water may need to be flushed more often. After flushing your heater a few times, you will discover the schedule that is right for you. Back to the top.