steam escaping from tub

[Steve]

Cool! Another fellow Edmontonian!

A number of items has been discussed already but to your original question... No, there shouldn't be steam escaping and certainly not to the degree we are seeing in your picture.

The cost of heat loss is tough to say but there certainly would be a cost associated to this. How old is this cover? Is it heavy?

The cheapest solution that will aide at this point is a solar cover that floats on the surface. There can be a gap between the skirt of the cover and the tub itself and I would always rather see a cover that's too big than too small. As Doc indicated, the skirt itself doesn't offer anything really with regards to an "insulation" factor.

If the cover is less than a couple of years old (in warranty), talk to the boys at Arctic. You may also want to check the top of your mold for trueness. We've seen a couple of posts recently where the mold itself isn't level and this can certainly cause what you're seeing. If the cover is more than 4 or 5 years, it will be due for replacement most likely.

Luckily, temps are quite nice right now in our fair city so it shouldn't be too much of a concern immediately.

Take care,

Steve

[lagator43]

Thanks Steve.  The cover is about 6 months old and the cover I had before this did not have steam escaping.  I am going to call Arctic after Christmas and get them to replace it.  

Go Oilers Go!

[Dr. Spa™ Ret.]

When the cover is closed, there's absolutely no vacuum beneath it. When you open the cover, yes, the skirt may "suck in", but that's due to air now attempting flood in to fill the larger void created by lifting the cover. As you begin to lift the cover there's isn't enough space to allow air to FREELY flow in to fill the space created by opening the cover.

Lift the cover very slowly, and it will lift right up. This is due to the air needing to enter under the cover more slowly.

A simple example of this would be an old fashion fireplace bellows. Pump it slowly, and it easily moves up and down, pump more quickly and it becomes more difficult.

None of this has any bearing on the insulating ability of the cover.

 

Try lifting the cover without creating a vacuum.  If the skirt is continuous, it will draw tight to the shell when lifting.  The air draw is the cover "sucking air" in as it is lifted.    This minimizes the movement or loss of air while the cover is in place and passing wind is not pulling or drawing air from under the cover.  If the corners are split, the vacuum is less effective.  With a continuous skirt, they at times bunch up in the corners and need to be straightened out, where split corner skirting "flaps" allowing the skirt to not bunch up at the corners.  

I am of the opinion that the cover skirting has a more meaningful purpose than just to shade the sun light.  If I had a cover without the skirting, the wind would be getting uner it and picking it up all the time.

[Brewman]

Doc's explanation makes sense to me.  Especially considering he makes covers for a living and all..............

[clover]

When the cover is closed, there's absolutely no vacuum beneath it. When you open the cover, yes, the skirt may "suck in", but that's due to air now attempting flood in to fill the larger void created by lifting the cover. As you begin to lift the cover there's isn't enough space to allow air to FREELY flow in to fill the space created by opening the cover....None of this has any bearing on the insulating ability of the cover

I agree with the beginning of your statement 100%, there is no vacuum until you lift.  When you do lift and it draws tight, it is, as you say, because of the inability of air to easily enter and fill the opening.  This is good, as it inhibits the seepage of air whether it is in or out with a continuous skirt.  The ability for air to escape happens to be the other side of that coin.  You will not have icicles hanging from your cover.

IF you say the skirt has no bearing on the insulating qualities of a cover, you must not live in the "snow belt" where we experience freezing temperatures daily for months at a time.  Icicles are created by warm air escaping and freezing on contact with the frigid air.

I have never found icicles hanging from a D-1, or Marquis cover which have continuous skirting.  But, like Marquis, some of the upper end makers are very particular about how their covers are made.  They export their products around the globe to all weather climates and they know their product will be judged by the end user regardless of where he lives.

IF you don't live in an area that reveals this weak spot, it would be easy to dismiss the importance of a continuous skirt for the cover.  If it has no bearing on heat retention, why the icicles?  And then, why no icicles on the D1's?  Could it be less air loss, or heat loss, maybe?  

Like Marquis, D1 covers are made by Sunstar and they are not inexpensive.  We replace a lot of covers every month.  No matter how you cut it, you are going to replace your cover sometime, but better quality covers last longer and less costly covers do not perform to the standards of the better covers.

[Gomboman]

The vacuum you feel is the suction of air as the cover is lifted up.  The wet edges enhance the seal as it is lifted, but it is all about the air that draws the vacuum.  I do not believe your statement "no insulation, no vacuum whatsoever," is accurate.  But then, many covers are made differently, and they vary by manufacturer.

I've never noticed any type of vacuum action with my HS cover when I open it up? I always thought there was something wrong with my cover. After listening to Doc's explanation, I'm thinking the "vacuum" that most people describe is actually stiction between the bottom of the cover and the top surface of the shell. I vaguely remember this from one of my college physics classes.

Here's a Wikimedia definition:

"Stiction is an informal portmanteau of the term "static friction" ([ch956]s), perhaps also influenced by the verb "stick".

Two solid objects pressing against each other (but not sliding) will require some threshold of force parallel to the surface of contact in order to overcome static cohesion. Stiction is a threshold, not a continuous force."

[Vinny]

I've never noticed any type of vacuum action with my HS cover when I open it up? I always thought there was something wrong with my cover. After listening to Doc's explanation, I'm thinking the "vacuum" that most people describe is actually stiction between the bottom of the cover and the top surface of the shell. I vaguely remember this from one of my college physics classes.

Here's a Wikimedia definition:

"Stiction is an informal portmanteau of the term "static friction" ([ch956]s), perhaps also influenced by the verb "stick".

Two solid objects pressing against each other (but not sliding) will require some threshold of force parallel to the surface of contact in order to overcome static cohesion. Stiction is a threshold, not a continuous force."

Don't forget the surface tension of the water on the 2 surfaces.

[Tom]

My son just noticed the steam escaping from our tub the other day.  How much $$$ money is this problem costing me. Keep in mind that I live in Edmonton Alberta and we have had a cold winter so far. Help

Although I've never seen it myself, one of our Customer Service guys tells me that this is not uncommon and can occur in many brands of cover.  The Arctic cover has a full-length insulating baffle as well as two end baffles to prevent  heat loss.  "It's not a significant loss and won't damage the cover, so tell the customer there is no cause for concern," said the CS rep I talked to.
 
The CSR didn't say this, but it appears from your photo that moist air is escaping through the seams.   Pushing the two halves together should 'pinch' the baffle more firmly (thanks to all who already mentioned this) , and maybe in the summer you might apply some seam sealer to the seams.  And if you use a cover lifter, be sure to use the Cover Savers with it, as this will prevent  the seams from being stretched by the weight of the cover.

To answer another question in this thread, the Arctic cover extends approximately 1" on either side.  The skirt extends to cover the lip of the acrylic and the cedar rail for weather protection.  The skirt itself does not offer additional insulation nor is it intended to seal the cover to the spa.

[lagator43]

Although I've never seen it myself, one of our Customer Service guys tells me that this is not uncommon and can occur in many brands of cover.  The Arctic cover has a full-length insulating baffle as well as two end baffles to prevent  heat loss.  "It's not a significant loss and won't damage the cover, so tell the customer there is no cause for concern," said the CS rep I talked to.
 
The CSR didn't say this, but it appears from your photo that moist air is escaping through the seams.   Pushing the two halves together should 'pinch' the baffle more firmly (thanks to all who already mentioned this) , and maybe in the summer you might apply some seam sealer to the seams.  And if you use a cover lifter, be sure to use the Cover Savers with it, as this will prevent  the seams from being stretched by the weight of the cover.

To answer another question in this thread, the Arctic cover extends approximately 1" on either side.  The skirt extends to cover the lip of the acrylic and the cedar rail for weather protection.  The skirt itself does not offer additional insulation nor is it intended to seal the cover to the spa.

What is a Cover Saver?

[Dr. Spa™ Ret.]

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