Filtration in hot tubs

[DPS]

As far as the filter bypass goes, Marquis single pump models have zero bypass.  Everything goes through the filters - period.  On two pump models, the primary pump still has zero bypass.  It is still filtering with no by pass when the jets are on high speed.  The second pump does by pass the filters.  On high speed in a Marquis Spa you still have 120gpm or 160gpm being filtered with absolutely no by pass when the jets are on high speed (120gpm on 120v convertible models and 160gpm on 220v models).

[Spatech_tuo]

As far as the filter bypass goes, Marquis single pump models have zero bypass.  Everything goes through the filters - period.  On two pump models, the primary pump still has zero bypass.  It is still filtering with no by pass when the jets are on high speed.  The second pump does by pass the filters.  On high speed in a Marquis Spa you still have 120gpm or 160gpm being filtered with absolutely no by pass when the jets are on high speed (120gpm on 120v convertible models and 160gpm on 220v models).

OK, that's how I figured. I thought they were doing something different that I was unaware of.

[shabba34]

Hey DPS,

What sq ft are the filters on the spas?  50 a piece?

[MarKee]

50 sq ft or 35 sq ft.  Both are available.  They now come from the factory with 35 sq. ft.  

[Bonibelle]

So Markee are you saying that my Epic probably has the 35 sq ft filters but when I buy new ones I can go with the 50?  With more square feet of filter area does that mean you can go longer between cleaning? Or are the filters rated for the volume in the tubs, or number of  pumps or what?  :-/

[shabba34]

50 sq ft or 35 sq ft.  Both are available.  They now come from the factory with 35 sq. ft.  

My question is how can the spa filter 160 gpm when there is only 70 sq ft of filtration without a bypassing??

[drewstar]

My question is how can the spa filter 160 gpm when there is only 70 sq ft of filtration without a bypassing??

Just a guess:

The 70 sq ft of filter is the surface area of the filter cartridge.  So how much water would need to pass through a square foot of  filter membrabne to achieve 160 gpm?

2.3 gallons per minute.   Is that not possible?  Or did I miss something?

[shabba34]

Just a guess:

The 70 sq ft of filter is the surface area of the filter cartridge.  So how much water would need to pass through a square foot of  filter membrabne to achieve 160 gpm?

2.3 gallons per minute.   Is that not possible?  Or did I miss something?

Yes, that is true, but not without minimizing the micron capabilities of the filter and starving the jet pump for water.  Water is moving through too fast causing a lot of back pressure.  This causes deminished jet pressure and lack of filtration capabilities.  Rule of thumb is 1gpm per 1sq ft of filtration.  Remember also, that dirty filters further hinder the situation.  I realize that the claims of the no bypass during filtering are true, just not at the gpm's that were stated.  Commercial or residential pools will allow for up to 3gpm to 1 sq ft of filtraton, however not recommended due to reasons stated above.  Most contractors will equally match the filter sq footage to the size of the pump.

[MarKee]

When you pull from 360 degrees around the filter instead of one direction (the direction of the wier gate), it's amazing what you can accomplish!

[East_TX_Spa]

What I've never understood (and maybe someone can explain it to me) is why all of these companies that "filter 100% of the water" put by-pass valves in their spas.  Don't by-pass valves do exactly that....by-pass the filters?

I'm anxious to hear the answers.

Terminator

[drewstar]

What I've never understood (and maybe someone can explain it to me) is why all of these companies that "filter 100% of the water" put by-pass valves in their spas.  Don't by-pass valves do exactly that....by-pass the filters?

I'm anxious to hear the answers.

Terminator

Well that's why they need to change the water over many many times.  Eventually you'll get it all.   Even with No By pass filtration,  not all the water in the tub gets filtered on the first change over.   It's "All the water entering the pumps" gets filtered.  

no?

[hymbaw]

When you pull from 360 degrees around the filter instead of one direction (the direction of the wier gate), it's amazing what you can accomplish!

Sales deception!!!!!

Are you saying that when the pump sucks the water out of the center of the filter, the vacuum created in the center of the filter can determine which side of the round filter the wier gate is on?



B S !!!

[East_TX_Spa]

When you pull from 360 degrees around the filter instead of one direction (the direction of the wier gate), it's amazing what you can accomplish!

[shabba34]

What I've never understood (and maybe someone can explain it to me) is why all of these companies that "filter 100% of the water" put by-pass valves in their spas.  Don't by-pass valves do exactly that....by-pass the filters?

I'm anxious to hear the answers.

Terminator

They filter without a bypass only during filtering cycles with pump on low speed.  In essence, when your not using the spa.

[East_TX_Spa]

They filter without a bypass only during filtering cycles with pump on low speed.  In essence, when your not using the spa.

Oh.  I guess using a little bit of common sense would then dictate there is probably a little more hair, dead skin, toenails, dirt, and buttcheese in the spa when there are actually people USING the spa.

That's when I really like to have my water clean.  Before and after is nice, too.

Terminator