If you're hearing a hiss, you're likely hearing escaping air. This could be caused by an improperly installed air filter, or one that is the wrong size. Often having too many closed vents, or having furniture blocking air flow can be the cause of a hissing sound.
Your radiator heater may be hissing air for about 30 minutes due to air trapped in the system. This is a common occurrence when air gets trapped inside the radiator or pipes. The hissing sound should subside as the air is purged from the system and replaced by water.
Most radiators should be bled every year or so. Sometimes, the bleed valve will loosen itself, or someone might not have shut it tightly enough the last time they used it. Bleeding the radiator and closing the valve tightly should stop the hiss.
The potential fix for a hissing water heater depends on the root cause of the problem. Adjusting the temperature setting may solve the issue if the temperature is too high. However, if there is a leak or sediment build-up, it is best to call a plumber to inspect and repair the water heater.
Weird hissing sounds are caused by low pressure of cooling agent in system, and it is too low because something (like some connection o-ring seal) in system is leaking. Faulty seals must be detected and fixed, and then system re-filled. Another option, unplug conditioner pump connection and disable this system forever.
Hissing Sound From Heater Core
Either way, if you can hear a hissing sound from the heater core then it's a problem that will need rectifying as soon as possible. Make sure you act quickly to prevent significant long-term damage being done to the engine.
A hissing or whistling radiator is caused by too much air leaving your radiator and you might need to replace the air vent. Replacement air vents can often be found at your local hardware store at an affordable price, but be sure to consult with a heating engineer before purchasing them.
One of the most common reasons for a hot water heater to make a hissing sound is because condensation is coming into contact with a hot surface. This sound will often occur after a long shower or when the dishwasher is running — any time you use a large amount of hot water — and is a fairly normal occurrence.
Old furnaces rarely made running water or gurgling noises because there was no condensation or liquid involved. Today, newer and high-efficiency furnaces produce condensation, which is why your furnace may sound like there's running water somewhere.
Most homeowners should flush their water heaters every 6 months or so, but if you have extremely hard water, you may want to do it more often. Flushing your hot water heater could be necessary as often as every few months depending on the mineral content of your local water supply.
Any odd noise coming from a furnace, boiler, or heat pump could mean something in the system has malfunctioned and is in need of repair. While low humming sound is typical when heating systems operate, any sound that is not common coming from the furnace or heat pump could mean a problem is present.
When recording, you can eliminate the noise by removing noise sources such as a fan or a computer. You can also reduce the hissing sound by placing the microphone closer to the subject. Another way to eliminate hissing noise is to turn off the auto-gain settings in the camera.
Tinnitus is one possible reason, but there are also myriad other causes of a hissing sound. Medical conditions like high blood pressure, reactions to medications, and injuries to the head and neck can also prompt a hissing noise or cause the perception of this sound.
Condensation may cause sizzling and popping noises within the burner area during heating periods. Water hammer noises due to high water pressure in the home's plumbing system can result in leaking water heaters, banging water pipes and excessive wear on appliances.
Loud Bangs, Rumbles, Knocks, or Booms
Loud noises like this are a sign of a build of gas in a furnace. The noise you hear can mean your heat exchanger is at risk of cracking. Even worse, it's a sign that something dangerous could happen if you continue to use your heater.
From hissing and popping to knocking and clicking, a noisy water heater can be more than just a nuisance. It could be a sign that your water heater needs some maintenance or repair.
The operation of your water heater can also contribute to sounds of water movement within the pipes. As the heater heats water and sends it through the plumbing system, you may hear a gentle flow or ticking sounds. These noises are typically associated with the normal function of the water heating system.
When you hear a hissing sound from your furnace, something similar is probably happening – this is usually the sign of a leak. This could be a leak from an improperly installed filter or an incorrect filter size. It is also possible that there is a leak in your ducts.
Hissing - from a water heater tank means that there might be too much air disrupting the system. Hissing from the pipes means that there might be leakage and air is let through together with the water.
As the water heats up and runs through the system, the copper also heats up and expands. As the pipes expand, they may be able to brush against other surfaces, like walls, joists, brackets and floorboards, causing a creaking, groaning or gurgling noise.
If you're hearing frequent hissing and seeing moisture on or around your water heater tank, it is a sign of an internal tank leak. As we mentioned earlier, excessive sediment buildup can cause tears and leaks in your tank, wasting a substantial amount of water (and money).
Radiators move hot water or steam, so they may hiss from time to time. A stuck or clogged air vent can cause a hissing sound. Radiator leaks may lead to hissing noises. You may need to bleed the radiator to fix the hissing.
Understanding Water Heater Noises
Gurgling or boiling sounds are usually a sign of sediment buildup, causing water to overheat and produce steam bubbles. Popping sounds are caused by water trapped under the sediment layer, indicating a need for tank flushing to remove the sediment.