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Exploring the Causes of Unpleasant Hot Tub Thermal Cover Stink

Exploring the Causes of Unpleasant Hot Tub Thermal Cover Stink

Is there a funky smell coming from your hot tub thermal cover? Is it totally ruining your chill vibe? Sometimes you can fix a stinky hot tub cover quickly and easily, but if the smell lingers and your cover is holding water, it’s time to say goodbye and get a new one. The first order of business is figuring out where that smell is coming from and how to make it disappear!

There are several reasons why your cover may be taking on a peculiar stink. In most instances though, the smell is due to the spa water condition. Maintaining the proper water balance and sanitizer level usually prevents odoriferous covers.


Understanding the Importance of Hot Tub Thermal Cover:

Hot tub thermal cover play a vital role in maintaining the water temperature and conserving energy. By trapping heat and preventing it from escaping, these covers help to minimize heat loss and reduce the energy required to keep the water warm. Moreover, thermal covers also act as a barrier against debris, leaves, and other unwanted materials that can find their way into the water. Additionally, by preventing evaporation, thermal covers help to conserve water, reducing the need for frequent refills.

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Identifying Common Causes of Unpleasant Odors:

A hot tub is an opulent addition to any garden haven, offering mental and physical healing as well as relaxation. But nothing detracts from the enjoyment quite like a bad smell coming from your swim spa cover. It’s not only unsettling, but it may also indicate deeper problems that require attention. We’ll look at a few typical reasons for these disagreeable smells in this blog post and offer practical advice on how to get rid of them.

Moisture Accumulation:

One of the most common causes of unpleasant odors in hot tub thermal cover is moisture accumulation. When the cover is not properly ventilated or if water is allowed to seep into the swim spa cover, it creates a breeding ground for mold and mildew. These microorganisms thrive in warm, damp environments, and their growth can result in a foul smell emanating from the cover. To prevent moisture buildup, it is important to ensure that the cover is properly dried before closing it and to regularly clean and inspect the cover for any signs of mold or mildew.

Chemical Imbalance:

Another common cause of unpleasant odors in hot tub thermal cover is a chemical imbalance in the water. If the chemical levels are not properly maintained, it can lead to the growth of bacteria or algae, which can produce foul-smelling compounds. To avoid this issue, it is essential to regularly test the water and adjust the chemical levels accordingly. Maintaining the proper balance of sanitizers, pH, and alkalinity will not only prevent odors but also ensure the health and safety of those using the hot tub.

Reason for Unpleasant Odors in Hot Tub Thermal Covers

Unpleasant odors emanating from your hot tub thermal cover can quickly ruin the tranquility and enjoyment of your spa experience. Understanding the potential causes and implementing the appropriate solutions is key to escaping the clutches of these odorous invaders. By addressing moisture accumulation, maintaining proper chemical balance, cleaning regularly, and keeping the surroundings tidy, you can ensure a fresh and inviting atmosphere every time you indulge in your hot tub oasis.

Outer Jacket:

Determining the source of the odor requires some elimination approach. To begin, remove the quilt from your tub and place it in an area where it may be spread out. Remove the jacket’s zipper and the foam cores with caution.

Check the outer jacket thoroughly for holes or tears. With a vinyl patch kit, small to medium-sized holes or tears can be repaired. Excellent results are obtained when the spa jacket is thoroughly cleaned and dried before performing maintenance. Your spa cover jacket has to be replaced if it has large holes in it or if the fabric is deteriorating.

Find out here how to take care of spa cover and lifter.

Core Liner:

To keep moisture out, spa cowl foam is covered with a vapor barrier, which is a protective plastic liner. Look for splits or holes in the seams of the liner.

Try drying the foam and using a patch bundle to fix the liner if the middle vapor barrier of the foam has been opened or pierced but the foam isn’t saturated with water. It’s time to replace your cowl if the rip or hollow is just too large to repair or if the foam center is saturated.

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Broken or Cracked Foam:

Broken or cracked foam cores mean your swim spa cover will lose its form, eventually allowing it to make contact with the spa water. Any contact with the water will lead to further deterioration. In this instance, replacing your cover as soon as possible is best.

Trapped water inside the foam stagnates pretty quickly and starts to stink. Once your spa cover foam is waterlogged, it no longer provides any heat retention, causing your electricity bill to soar.

Spa Cover Cleaners:

It makes sense to use non-abrasive, oil-free cleansers made especially for your hot tub and cover. Although there are alternative cleaners available, these may eventually cause damage to your swim spa cover. Additionally, cleaners not meant for use with hot tub covers may find their way into your water and result in a chemical imbalance.

Spa Cover Cleaners


To keep your spa cover looking like new, you must maintain it and use water. Establish a monthly schedule for spa cleaning that includes cover-ups.

  • Make an effort to maintain your cover’s top clear of dust, debris, and grime. This will shield your cover from harm and stop foreign objects from entering your water.
  • You can prevent fading and cracking of your cover by using 303 Aerospace Protectant.
  • Use of silicone oil-based treatments is not advised as this will hasten degradation and sun damage.
  • To let it air out, remove your cover every few months and store it in a dry, safe area.
  • To shield your cover from moisture and excessive chemical evaporation, use a floating spa blanket.
  • Ensure that the water in your spa is adjusted correctly. Water that is out of balance can promote the growth of microorganisms or damage your cover. Bacteria can build in and on your spa cover if the water is not kept clean. Explore the lightweight hot tub covers.


Maintaining a hot tub is a responsibility that comes with numerous rewards. By understanding the causes of unpleasant odors in hot tub thermal covers and implementing the prevention and maintenance tips provided in this blog post, you can ensure a stink-free hot tub experience. Regular cleaning, proper ventilation, and maintaining a chemical balance are essential in preventing odors and keeping your hot tub clean and inviting. Remember to regularly inspect your swim spa cover, replace it when necessary, and follow good hot tub maintenance practices to enjoy a fresh and enjoyable hot tub experience.

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