Sounds like you’re not pushing enough cool air through the heat exchanger, which means it can’t dissipate the heat fast enough. With a conventional gas furnace, you should be at about 140°F-170°F at the supply plenum. A high efficiency furnace will be lower, around 110°F-140°F.
Herein, how hot does furnace heat exchanger get?
A blower fan blows air through the heat exchanger and then into ductwork that distributes the heated air to vents around your home. When the combustion occurs and air is first heated, the temperature is between 140 degrees F and 170 degrees F.
Furthermore, what does a heat exchanger look like on a furnace? A furnace’s heat exchanger is a set of tubes or coils that are looped repeatedly through the air flow inside your furnace for the purpose of heating air. Simply put, the furnace heat exchanger is the part of your furnace that actually heats the air.
Besides, how hot should the air coming out of my vents be?
Heat pumps usually produce air that is 85-92°F. This is plenty warm to heat your home to your desired 72°F. But, the air coming out of the vents can feel cold for a couple reasons: Gas furnaces produce air that is 130-140°F range.
What are the symptoms of a damaged heat exchanger?
3 Signs Of A Bad Heat Exchanger
- Cracks. A cracked heat exchanger is one of the most basic and common symptoms, and also often the most drastic sign of a damaged heat exchanger.
- Discoloration. Sometimes a cracked heat exchanger has cracks that are simply too small and thin to be directly observed.
- Odd Furnace Flame Behavior.
17 Related Question Answers Found
Can a cracked heat exchanger cause a fire?
Cracks in the heat exchanger or “Fire Box” is no laughing matter. There are two major dangers with having a broken heat exchanger: The first is the potential for the furnace to catch fire and potentially spread to other parts in the home. The second danger is carbon monoxide emissions.
Can I run my furnace with a cracked heat exchanger?
If it is your heat exchanger, you cannot run your furnace, even if it seems to be running fine. The gases will continue to seep into your home’s air. Many companies, upon finding a cracked heat exchanger, will shut your furnace down so you cannot run it.
Should my furnace be hot to the touch?
Most single stage furnaces should be just uncomfortable to touch on the main trunk just above the main unit. As Heat rise levels can range from 50-70 higher than ambient air temp. Yes, it’s normal.
What makes a furnace overheat?
A clogged air filter restricts airflow through the heat exchanger, causing the furnace to overheat. The high-limit switch detects the dangerous overheating and signals the computer to shut off the burners and run the blower fan to cool off the heat exchanger. Once the furnace cools, the computer tries to fire up again.
How do I clean my furnace?
How to Clean a Gas Furnace Turn off power/gas to the furnace. Turn off power to the furnace at the breaker box. Clean furnace surfaces. Wipe exterior surfaces with a damp rag. Remove the blower. Carefully clean the blower. Clean the pilot or hot surface igniter. Clean the flame sensor. Inspect the drive belt. Lubricate (but not too much).
What is the function of heat exchanger?
This arrangement is what we mean by a heat exchanger: the gas jets cool down and the water heats up. A heat exchanger is a device that allows heat from a fluid (a liquid or a gas) to pass to a second fluid (another liquid or gas) without the two fluids having to mix together or come into direct contact.
Why does cold air come out of the heat vent?
Explanation: Leaks in your ductwork means that cold, unconditioned air from inside your attic gets sucked into your ductwork. That cold air mixes with the warm air from your furnace, causing the air coming from your vents to feel considerably cooler than it should.
Why does my heat feel like cold air?
You see, a heat pump heats your home by moving heat from the outdoor air into your home. But as it gets colder, and your heat pump can’t pull as much heat in from the outdoor air, the air coming from your vents drops slightly in temperature. If so, your heat pump is blowing warm air that just feels cold to you.
Why is my furnace blowing lukewarm air?
The lukewarm air coming out of your furnace can also be the result of leaky air ducts. If your ducts are leaking (and ENERGY STAR says that almost all homes leak about 30% of the air in their ducts), cold outside air is making its way into your ductwork. This can cause the air to feel only lukewarm.
How cool should my house be if it’s 100 outside?
More specifically, for our area, most systems are designed to lower your indoor temperature about 20°F from the outdoors. So, on days when it’s 100°F outside, and your system is running at its peak efficiency, your indoor temperature will likely never maintain a level lower than about 80°F.
How often should you change your furnace filter?
every 90 days
How many degrees should an air conditioner cool?
15 to 20 degrees
Why is my furnace not putting out heat?
Dirty filters are the most common cause of furnace problems. Dust and dirt restrict airflow—and if the filter gets too clogged, the heat exchanger will overheat and shut off too quickly, and your house won’t warm up. If the blower is running but no heat is coming out, replace the filter.
What happens when heat exchanger fails?
The problem is that all heat exchangers will eventually fail, developing holes or cracks that allow those poisonous gases to leak out and contaminate your home’s air. These leaks can be extremely dangerous, even deadly. In fact, cracked heat exchangers are one of the major causes of carbon monoxide poisoning in homes.
What causes a heat exchanger to crack?
The most common cause of an overheated heat exchanger is as simple as a dirty air filter. A clogged air filter restricts airflow through the furnace, overheating the heat exchanger, and eventually resulting in stress cracks. An over-sized furnace can also cause overheating and heat exchanger cracks.
Can a heat exchanger be replaced in a furnace?
Your HVAC technician will replace the heat exchanger so your furnace will function safely. Heat exchangers offer a typical service life between 10 to 20 years – depending on the life of your furnace and other factors, you may decide to replace the entire furnace if the heat exchanger requires replacement.
How long should a furnace last?
15 years