Questions on a New Hot Tub

[Daf-Tekno]

Hi,

We're looking at new hot tubs, and want some clarification on a few points:

The Maax Spa dealer has combined UV / Ozonator units on his tubs.
He says the UV acts not on the water but on the Ozone, turning it into a much more powerful sanitiser.
Because of this, you hardly need any chlorine, just a little after you've been in.
No need for any other hygiene system.
He says he wants you to have essentially bath water in which to relax, no chlorine, no salt. You add a little chlorine as you get out.

The Arctic Spa dealer also has combined UV / Ozonator units, but also has salt water chlorine generators installed as well.
It appears to be that:
1. he doesn't understand how his combined UV / Ozonator units work
2. he does but wants to sell a SWG with each tub anyway
3. His combined units don't operate like the Maax units, and merely shine the UV onto the water, then inject Ozone as two separate actions (even though they look virtually identical)
4. The Maax guy is mistaken

The Sundance Spa guy said his tubs come with Ozonators and can also have an Ioniser unit fitted, again greatly reducing the need for chlorine.

I heard that SWGs, because the tub water then becomes salt water, are actually very bad for the tub, as all the components get hammered by the salt water, and fail far earlier than otherwise.

Can anyone advise on:
1. Combined UV / Ozonator units (where the UV turns the Ozone into something far more aggressive)
2. UV / Ozonator units with SWGs
3. Ioniser systems
4. If SWGs are damaging to a hot tub

Thanks - D

 

[YippeeSkippy]

I use a Saltron Salt Chlorine Generator in my Sundance spa and it makes things like sanitation a lot easier and I never give a thought about those alternative hoohas that the dealers try to sway you with
.

https://www.spadepot.com/docs/Saltron-Mini-Manual.pdf

Maddie

 

[Newdude]

Hey Daf !!!

1). Two totally different functions. One does not turbocharge the other.

2). Ozone leaves no residual sanitizer. Need 100% chlorine treatment anyway.

UV leaves no residual sanitizer *and* will eat your 100% chlorine anyway treatment. (Not all of it, but still. It’s supposed to help and not hurt). UV does help in a hot tub to burn off some of the CCs that don’t burn off in the mostly covered tub, so it’s not a total waste, but it’s questionable at best if it helps enough to matter. Opening the cover for 3 minutes on a sunny day will burn the CCs off for free.

SWG will do great maintaining chlorine all the time it’s not being used. It’s super easy to dump some in after your soak to replace what you just used. Then you pretty much won’t have to think about it until next time. (Once it’s all dialed in).

4). Some say they are, but many members have been using them for years without trouble. ‘Salt’ pool/spa water is around 10% of sea water. Most of what you add to the water contains salt. In the tub, you dump it out and start fresh once or twice a year, so it doesn’t compound like it does in the pool, but still. The entire salt argument hinges on whether it matters going from 3% of ocean salinity to 10%.

 

[RDspaguy]

OK. Ozone is a strong oxidizer and will burn off combine chlorine and free chlorine in the water. This is what it is for. It does not mean that you do not need chlorine is or will use less chlorine. It simply means that there will not be a chlorine residual in the water when you open the cover to use it.
I have read a study that said certain wavelengths of uv will produce hydrogen peroxide in water just as they produce ozone in air, but can't say for sure myself. What is known is that uv light, from a uv system or the sun, will burn off chlorine. This is why pools are stabilized.
Both ozone and UV systems will destroy organic contaminants in the water. They both suffer from the same drawback, however, in that they only treat a small portion of the water at a time then return that water to an untreated tub. Since there is no residual, chlorine (or some other sanitizer) must still be used with either system. A salt system can be the source of that chlorine. I personally do not recommend salt systems in spas but not because of the salt. It is user error or system malfunction that can damage the spa.
An ionizer is a silver ion system also known as a mineral purifier. It uses cartridges that are replaced periodically, and also requires the use of a chemical sanitizer or mps.
I like ozone used with chlorine on a 24/7 injection system like Sundance has. I also like a mineral purifier with it. But I add chlorine after each use.

 

[Daf-Tekno]

We've been looking at new hot tubs, and both the Bullfrog and Maax dealers say their tubs are at the top of the list of most efficient hot tubs.

Bullfrog say the list on the Californian Energy Commission website, the Maax guy says it's on the Californian Energy Group website.

We've searched both and can't find any trace of any such list.

Is there a list of hot tubs in order of energy efficiency, or are we being taken for a ride?

The Maax tubs have an energy consumption sticker on the side, from the Californian Energy Group, but we can't find any list related to this entity.

This stems from our attempt to try and get to the bottom of which type of insulation is best:
Perimeter or foam-sprayed bottom.

Arctic state perimeter is far better, with their tubs being able to stand without power in Canadian Winter weather for 5 days before any risk of the water freezing, whereas non-perimeter tubs will freeze in a matter of hours.

But another forum stated that using the R-values, perimeter tubs needed 3 - 4 times the energy compared to spray foam tubs.

Clearly they can't both be correct.

Any help much appreciated.
Thanks - D

 

[Mdragger88]

I am not in the frozen north so I didn’t have the need to research too much on insulation but
@RDspaguy may have some helpful input for ya!

 

[RDspaguy]

If r-value were the only factor to consider, it would be an easy choice. But each type of insulation has advantages and disadvantages. And since most of the heat is lost from the top it's a highly over-rated subject, and not much more than a marketing ploy.
Full foam costs alot more to fix any leaks. Far more than the insulation will save you over the life of the spa. But it will likely have fewer leaks not the result of poor chemistry (the #1 cause of jet gasket leaks).
Any spa, turned off in freezing temps, will freeze. It will freeze the equipment first in a full foam spa, sometimes saving the plumbing in the foam. It will usually freeze the equipment first in a "perimeter" tub as well, as those usually have a foam spray on the pipes and shell too. As with anything involving freezing water, the starting water temp and ambient air temp play the main role, and if a tub actually made it 5 days it was screaming hot to begin with and had ambient temps right around freezing, and was probably in the sun all day too. More marketing BS.
Buy the tub you enjoy, and stop worrying over the specs.

 

[Daf-Tekno]

Hi,

We're looking at new hot tubs, and I've had a wet test of a Maax and a Sundance tub, but for some reason, in my mind they don't seem to have as much pressure coming out of the jets as our old Jacuzzi J480.

Does the J480 have unique high pressure jets, or is my memory playing tricks on me?

I believe the Sundance has essentially identical pumps, so the water pressure should be almost identical.

All I can think of is the jets must be significantly different, but if Jacuzzi jets were THAT much better then everyone else's, then they'd have a reputation that I have yet to hear about.

So that can't be the case.

But I suspect each manufacturer has their individual 'edge' by having their own slightly different jets, so there may be something here.

Or is my memory playing just tricks on me?

Sorry, I didn't know which area of the forum to place this post.

Thanks - D

 

[RDspaguy]

Jacuzzi bought Sundance, and built the j-series in imitation. But every model will be slightly different depending on # of jets, placement, diverters, pump hp, etc.

 

[PoolBrews]

Take a look at TuffSpas. They have the only patented cover that is guaranteed for life, and serves as a shelf/bar when opened. Easiest opening cover I've ever had on a hot tub. Home - Tuff Spas

I've had mine for 5 years now, and it still looks and works like new. All of the parts they use are industry standard (no unique one off heaters, controls, pumps, etc) so you can get replacement parts anywhere. I haven't had to replace anything yet - it just works fantastic. I'll never own another make of hot tub after experiencing the ease of use of this one.

 

[Daf-Tekno]

One thing that has come to mind on this subject:

My J480 had 2 filters, a large one that I think fed the main pumps, and a slightly smaller one that I think fed the circ pump.

Together their combined surface area would be fairly big.

The Maax and Sundance spas didn't have quite the same total surface area of filter, I suspect.

If the same power pump is being fed with a more restricted input (i.e. less filter surface area) then I could understand that its output power / pressure would be less.

Indeed, a tub tech I spoke with the other day said one thing he did to address the output pressure of a tub was to increase the input piping diameter as much as possible.

Maybe this is the reason for the pressure difference I experienced..?

 

[RDspaguy]

One of many factors.

 

[DangerBoy]

@Daf-Tekno , I too am from Calgary and would like to chime in on the perimeter vs injected foam insulation question. I have a 27 year old Hot Springs Grandee tub that I bought used with a number of problems but now have running flawlessly. During the first couple of winters I had with that tub, I had a few breakdowns in very cold weather where it took me a number of days to get the parts needed and make the repairs. I was able to keep the tub from freezing by keeping the cover on, keeping the circulation pump running 24/7 (which they always do on a Hot Springs tub), placing a small space heater inside the engine room and keeping the door on the engine room closed to help keep the heat from the space heater from leaking to the great outdoors. In one instance, I went 5 or 6 days running in that mode when the outside temperatures here were in the -15 to -20C range (around +1 or 2 F - -1 or 2F) and the temperature of my tub water only dropped from 40C to maybe 33C (104F to 90-ish F). That's a LONG ways from getting into the freezing danger zone. I fully attribute this excellent thermal performance to the fact that the tub is foam injected/fully insulated. I do not believe a perimeter insulated tub would've fared near as well.

My Grandee holds 1893 L (500 US gallons) of water which holds a lot of heat but when the ambient temperature gets as cold as it can get here, that heat can be lost very quickly if the container holding that water is not well insulated. As an Engineer who understands a few things about heat transfer, heat loss and thermodynamics, I do not believe that perimeter insulation is a good idea for hot tubs in the climate that you and I live in. Yes, perimeter insulated tubs work fine here but they will be more costly to operate because they will require more electricity to keep them heated and they will lose heat and freeze up more quickly than a injected foam tub if they break down during one of our nasty cold snaps.

I look at it this way: Both types of tubs have their own advantages and disadvantages so you have to choose which advantages you want and which trade-offs you can live with. The perimeter insulated tubs are easier to find and repair leaks whereas it is very difficult and costly to do that with injected foam insulated tubs like my Hot Springs. On the other hand, injected foam tubs will be less costly to operate and can survive and keep from freezing much longer during a breakdown during a cold snap type situation like I've been through a number of times.

But there's another advantage of the injected foam insulation design that also needs to be considered: When the jet pumps are first turned on there is an initial large surge in pressure in the plumbing running to all of the jets the water is being pumped through. During that surge, the plumbing will perhaps want to expand a bit and perhaps want move or shake a bit as well. Over time, these movements can cause fatigue failures at stress points, joints and seals and these can eventually lead to leaks forming. But on a injected foam tub, the plumbing lines running to the jets are pretty much frozen in place so these pressure surge movements are greatly reduced if not completely eliminated. So while finding and replacing a leak in a injected foam insulated tub is difficult and costly, I believe they are much less likely to develop leaks due to material/seal failures caused by pressure surge movements. As evidence, I submit my 27 year old 1995 Grandee which, as far as I can tell, has no plumbing leaks whatsoever.

So there's the trade-off. Easier to find and fix leaks vs less likely to develop leaks plus I would argue better insulated, less costly to operate and can survive longer in cold weather with no heat (as long as you can keep the circ pump running.). What's your choice?

And if I can offer one more piece of advice: I would not buy any tub that makes one of its jet pumps do part-time duty as a circulation pump. It is very inefficient to try and make large jet pumps run at low speed to circulate water in the tub. I believe it is far more efficient to use a small low output pump to handle the circulation duties. As such, I would only ever buy a tub that has a small, dedicated low power consumption circ pump running 24/7 on its own circuit, separate from the jet pump circuits. This is why I like the way Watkins designs its Hot Springs tubs. Aside from the efficiency aspect, having a separate 24/7 circ pump can come in very handy when your heater has failed in the middle of a nasty cold snap. Keeping the tub water slowly and continuously moving through the engine room can be critical to keeping things from freezing in there. This is something that I know to be true as I have gotten my tub through several lengthy down times in very cold weather during the past few winters. This year, I've not had to do that so far due to some modifications I made. (Thanks @RDspaguy! ). I will post about those mods later, after the winter's over.

 

[phonedave]

@Daf-Tekno Do not subject yourself to analysis paralysis. You can become so obsessed with getting "the best" that you will never be happy. What is the point of agonizing over a tub with 40 psi jets and one with 45 psi jets if you would actually be happy with a 30 psi jet (I have no idea what psi jets run at, that is just an example)

I will say, if there is a feature that you really really want, then go for that - maybe you like your tub to light up like a rave, maybe you want a huge sound system, maybe you want a lounger, maybe not

Also, go with a good dealer. You could get the best tub model in the world, and if the dealer is no good with delivery, installs, and warranty service - it is going to be a poor experience.

As an aside, I like my Bullfrog. It seems to retain heat very well. I screwed up my economy schedule (apparently the difference between AM and PM is difficult for me to grasp) and my heaters were off for about 12 hours before I went to go in one night. My tub dropped from 103F to 96F in those 12 hours, and it was in the low 20's. I will be able to see how much power it uses when the bill comes this month. It has been single digits these last 2-3 weeks here.