How to check furnace intake?

Author: Gladyce Rogahn Sr.  |  Last update: Thursday, February 5, 2026

First, shut off the power to the furnace at the circuit-breaker box. Look for your furnace intake pipes, which are often white or black PVC pipes that exit a wall close to your furnace. Find where the intake pipes exit on the outside of your house. They are close to where your furnace is on the inside.

How do I know if my furnace has a fresh air intake?

To find a fresh air intake, look for a grilled vent near a gas appliance. The vent may be out in the open, but it can also be installed behind the appliance or a door. If you can't find it right away, look around and behind the furnace and check for an access panel.

How do I check my furnace airflow?

In general, you need to take a static pressure measurement on the return and supply side of the air handler. This kit is designed to easily and quickly perform this test. Compare this measurement to the manufacturer's max static pressure value. If the TESP is too high, it indicates there's an airflow issue.

How to clear furnace intake?

Unblocking a Furnace Intake Vent

A small brush is usually enough to clear debris off the screen. For more stubborn buildup, you can use a shop vac, but that usually isn't necessary.

How do I check my furnace intake?

HVAC Care
  1. Look at your furnace and find the plastic (pvc) intake and exhaust pipes. ...
  2. Go outside and look for the intake and exhaust pipes, based on where they exited the building when you looked at the furnace. ...
  3. Examine the intake and exhaust pipes, looking for anything that could be blocking the pipe.

High Efficient Furnace Exhaust and Intake Pipe Blockage Causing No Heat Calls

How do you clear an air intake?

Make sure the engine is cool to the touch before cleaning.
  1. Remove the filter. Take the air filter out, taking care to make sure no dirt or debris falls into the airbox or intake. ...
  2. Apply cleaning solution. Spray the filter with Simple Green All-Purpose Cleaner and let it soak.
  3. Rinse. ...
  4. Dry. ...
  5. Oil and replace.

How do I know if my furnace is venting properly?

#1 Moisture and Condensation

Increased moisture within the home is a sign that your furnace venting isn't adequate. Without proper ventilation, fumes from the furnace leak into your home and cause condensation. This moisture is most notable in the morning and when you first turn on your heating unit.

How do I balance my furnace airflow?

Here are 5 ways you can help balance airflow in your home.
  1. Check the Location of Your Thermostat. ...
  2. Keep Rooms and Vents Open. ...
  3. Adjust Ductwork (fix, seal, add new return ducts) ...
  4. Increase Insulation (windows, walls) ...
  5. Install an Air Handler or Zoning System. ...
  6. Call Lakeside for Professional Air Balancing.

What happens if the air filter is backwards?

The most common problem you will face with a backwards facing filter is simple inefficiency. If your furnace is forced to blow air through the non-porous end of a filter, it will take more energy to do so. The blower will be overworked and you will pay more money for your heating.

Can I add a fresh air intake on my furnace?

Can a fresh air intake be installed on an existing furnace? Yes, it can often be added to existing systems, but it's important to have this done by a professional to ensure proper installation and compliance with local codes.

How come my furnace is blowing cold air?

Your furnace will blow cold air if there is no air to heat and send back into your home. Another reason you may not be getting enough air flow is if your ductwork is not sized properly. Unfortunately, this is quite common. If your return ductwork is too small, it will not be able to take in the required amount of air.

How do I know if my air intake is bad?

Keep reading!
  1. Symptom 1: Air Filter Appears Dirty. Alright, let's start with the basics. ...
  2. Symptom 2: Decreased Gas Mileage. ...
  3. Symptom 3: Reduced Engine Power. ...
  4. Symptom 4: Unusual Engine Noises. ...
  5. Symptom 5: Misfiring Engine. ...
  6. Symptom 6: Rough Idling. ...
  7. Symptom 7: Reduction in Horsepower. ...
  8. Symptom 8: Hard Starts.

What happens if air intake is blocked?

The engine's combustion relies heavily on air, which mixes with fuel to generate energy. In the absence of a sufficient quantity of oxygen, an engine will not be able to generate power, and it may not even start. Whenever the air filter in your car's engine becomes too clogged, it may start to misfire.

Should furnace intake have a screen?

A common question that we receive is “should my intake and exhaust vents be covered with a screen?” The short answer to this question is yes. Sooner or later something is going to try to find its way into the PVC termination vents. It may be a bird, squirrel or even lawn debris like leaves.

How do I check my furnace air flow?

You can determine if your home has an air flow problem by performing the garbage bag air flow test – so named because the goal is to determine how long it takes for a garbage bag to fill with air (or whether it does it all).

How can I increase the air flow to my furnace?

Improve Airflow with a Booster Fan

Installing a booster fan in your HVAC system ductwork will increase airflow to rooms that are struggling to get warm air. A booster fan is a DIY trick that homeowners can use if they don't want a complete overhaul of their ductwork.

How much does it cost to balance air ducts?

How much does it cost to have your HVAC system balanced? Getting an air balance in HVAC systems, with no significant issues or modifications, can range from about $200 to $500. This typically includes airflow measurements, adjusting dampers, and ensuring proper temperature distribution.

Do all furnaces have fresh air intake?

Every home is legally required to have a fresh air intake if a gas appliance, such as a furnace, is installed.

What happens if there is improper venting of the furnace?

If the furnace exhaust can't provide proper airflow, there won't be enough oxygen for complete fuel combustion. Partially combusted gas molecules can pose a health hazard in your home if the furnace exhaust pipe can't disperse them outside.

How much airflow should be coming out of vents?

If you notice a change in the airflow of your HVAC system, then you should look into calling a professional. They can come out and test your equipment to determine how strong the airflow is. How strong should air come out of vents? The recommended airflow for each room is typically 50 cubic feet per minute.

How do I reset my air intake?

Reset the MAF sensor by idling your engine without the sensor installed for at least 10 seconds. You can also reset the MAF sensor by removing the negative battery terminal and waiting 10 minutes. You may be able to drive without the MAF sensor, but it's bad for your engine to drive without the sensor for too long.

How do you clean an HVAC air intake?

Steps To Clean Your Air Conditioner Vents
  1. Intro To The Guide. ...
  2. Remove the vents. ...
  3. Vacuum the ducts. ...
  4. Dust off your vents. ...
  5. Prepare some soapy water. ...
  6. Soak your vents for up to 15 minutes. ...
  7. Dry your vents with a towel and put them back on. ...
  8. Replace your air filter & turn your HVAC system back on.

How do you unclog an airflow?

Put the glass with the handpiece into the water-filled ultrasonic bath. If possible, set the temperature to 50°C (122°F) and activate the ultrasonic power at your usual setting for approximately 15 minutes. Rinse the AIRFLOW® MAX handpiece with tap water.

Previous article
What is the issue of white paper?
Next article
How do I stop smelling like old?