depending on where your furnace is located you could try putting some insulation or sound proofing the in area where the furnace is. if it is in an enclosed space try putting some on the walls in the space where it is located. this may cut down on the noise that you are hearing from the furnace.
If you're hearing a loud banging or booming noise, this could indicate your furnace has dirty burners. This is hazardous as it can hinder the ignition. This delay in ignition triggers a gas build-up, producing a little explosion when it finally does light. Your burners should be regularly cleaned to avoid this issue.
You'll probably have to remove an access plate to get at the ports. If the blower has grease cups instead of oil ports, remove the screw caps that cover the cups and fill the cups with bearing lubricant, which is available at automotive and hardware stores. When you lube the motor, you should also check the belts.
If it's the sound of the actual furnace you're hearing, you could add some sound deadening panels to the ceiling of your furnace room. If it's the ducts vibrating and making a noise, you could have them re-hung with acoustic isolators. Spray foam may help but it's not meant to be exposed.
On a normal day, your home's furnace might make a little noise as it starts up, when it's turning on, and then when it turns off. You can always expect to hear some noise from the furnace. The thing about this noise is that it should never be disruptive.
Use Sound Blankets and Barrier Walls
One of the most effective solutions for eliminating noise pollution is installing engineered HVAC sound barrier walls. Products like those offered by Sound Fighter Systems are designed specifically for HVAC noise reduction.
One of the more common problems in a blower motor is the bearings. Bearings surround the motor shaft, allowing it to run smoothly at high RPM with almost no friction. When the bearings go bad, the motor may make a grinding or screeching sound, or not run at all because of the friction preventing the motor from turning.
If your furnace produces a loud humming or buzzing sound, there could be an issue with the motor. There may also be something wrong with the fan. It can be something as simple as a loose screw, loose door, or improperly installed furnace filter.
For example, the Lennox SLP98V Variable-Capacity Gas Furnace is at least 50 percent quieter than competitor's furnaces, making the SLP98V gas furnace the quietest furnace you can buy1. SilentComfort™ is achieved by utilizing variable-speed technology. In other words, this furnace has a high and low speed.
If your furnace is making an obnoxious noise, it's likely because the furnace blower motor is turning on and off as part of normal heating furnace cycles. Make sure your thermostat is set properly to the desired temperature and off when you don't need heat (like overnight).
Check the flow rate of your boiler, a low water flow in the system can be a cause of the noise. (The correct flow rate can usually be found in the manual) If this is the issue, keeping it at the correct level will make the boiler function more quietly. Limescale can also be a factor that can cause a loud boiler.
Vaseline: you can use vaseline for all sorts of applications. It is a great lubricant for metal parts such as air installation, but it is also regularly used for installing PVC parts. Note: contrary to ball bearer grease, vaseline does become liquid at higher temperatures (40 - 60°C), causing it to drip.
Benefits of Grease
Besides, grease is the better lubrication choice for linear guide and drive applications. That's because it sticks to the bearing surfaces longer and is better than oil lubricants. Besides, it is less likely to run off or get ejected from rotating parts.
Use 1-2 drops of oil (not more, as it will attract dirt) or 3 mm grease evenly distributed around in the bearing. Make sure that the oil/grease is distributed well by spinning the bearings (can be done very effectively by mounting the bearing on a drilling machine).
The buildup of dirt and debris: The blower wheel and fan blades may get covered in dirt and other particles over time, creating an imbalance that produces loud noises. Your blower wheel component within your furnace will need to be cleaned by a professional technician.
You have a couple of options for lubricating the shaft and bearings of the blower motor. Spray lubricant, available at hardware stores, is sprayed into the oil ports. You may also inject the lubricant into the ports using a grease gun. Squeeze two or three drops of oil into each port.
Look at the float gauge on top of the tank to determine the level. If it is reading empty, you can be pretty sure you are out of oil. If that gauge indicates the tank is full, it could be stuck. Unscrew the plastic cover from the gauge and gently lift the disc to free the float inside the tank.
An HVAC duct silencer is specifically engineered to reduce airborne noise carried along ducts or produced by enclosures. You'll also find these silencers described as sound attenuators when they are used in industrial settings.
Much like a well-tuned orchestra needing regular practice, your loud AC unit requires regular maintenance for optimal performance. Dust, dirt, and debris accumulation inside an air conditioner is a common cause of noisy operation, and regular cleaning and lubrication of moving parts can prevent these issues.