magiline pools

[jpadie]

Hi

Does anyone have experience with magiline pools (with their fx30 filters and fxv motors)? I'd like to sense check something.

The pump has no suction side. It's just an impeller. Behind the pump the pool robot is connected to 25mm fittings. It's powered by a Venturi effect from the impeller.

I'm removing all the magiline system and replacing with a standard pump and sand filter. So far I've removed the turbine from the existing pump and replaced it but I am concerned that I will lose the robot if I do this.

There is a possibility of removing the pump altogether. Putting some reducers in the 50mm incoming pipe and plumbing directly to the 25mm robot outlet. However I assume that this circuit would be on the suction side of the new system (no way to tell for sure at the moment). Which might make a good solution for a barracuda type robot (?) but not for a Polaris that's currently there

I have an electric robot too (another Polaris). But it isn't up to much

Any thoughts?

Thanks
Justin

[Teapot]

Justin the best thing you can do with the 2nd worst system in the pool world. Are you going to add more return fittings or just keep to the one placed stupidly close to the skimmer?
Is the pump still working ok, I have a customer who's pump has just failed and we were discussing replacement of the whole system just as you are but if they can get through summer we'll do it in the closed season so if your pump is working we may want to buy it.

[jpadie]

I've got two skimmers (one each end). Each has a return too. There is a suction and return where the pump is (although the return is for the robot) and I have one further return by the steps.

There is also a drain but I can't say that I have ever felt it work nor have I ever known where the drain pipe emerges. If there ever was one. Perhaps something that the company charged for but never delivered on. Hardly uncommon...

My pump went last season. With magiline charging 800eur supply that's what stimulated me to change. And typically it takes me three-six weeks to open the pool each year, together with copious amounts of shock. It turns a pleasure into a chore.

I party disassembled my pump last week whilst removing the turbine. It's probably fixable as the coils don't seem burned out. Also I don't think it is that straightforward to remove the pump permanently as the pump is used to terminate that length of pipe. Perhaps when the whole pool is back working again I will feel able to remove the pump and weld in a reducer to go from 50mm to 25mm maybe with an inline tap to control the robot.

My total cost for a new system has been so far 550 EUR for a 22m3 sand filter, 340 for a 1.5hp super pump (triphase) 100eur for a VFD. I took the magiline salt system to bits in my electronics lab and repaired that so it worked (quite evidently it had never worked in 15 years). I've designed and built a prototype pH doser. Too. Cost of £20.

What is going to cost money and time is preparing the "point technique". Diggjng, concreting and putting a shed around the kit. But it will be much more accessible afterwards than the hole in the ground magiline left me with.

Disregarding the digging and concreting my costs have been less than a new motor and one filter from magiline. Or thereabouts. And adding in the VFD should make for a material power reduction going forward. I've built a controller for that too so it can be timed and remote controlled. Once it is all working I will build a sensor for orp and use that to control the salt system and/or extra liquid chlorine dosing.

[Teapot]

You have my applause. You'll have to do your upmost to prevent the short distance between skimmer and return from drawing in the water you have only just returned to the pool.
I am sure you have a flow switch connected for the chlorinator.

[jpadie]

Yes. That is a worry - how to counter the Venturi effect within the non-pump skimmers. I will have a proper look down there when I drain down the pool a wee bit. I'm thinking that it either might not be too bad or I might be able to print some inserts.


But I'm guessing at the construction. Assume that there is a genuine flow and return in addition to the venturi. Do you know of any diagrams for the FX line?

[Teapot]

Google images has a couple, very clear illustration.

[jpadie]

yup - but no info on how the flow and return are typically plumbed in accordance with magiline standards. i'm a bit lost as to how the whole thing works when the pump has no suction side!

[Teapot]

The pump is flooded (below the water line) so no real suction required it's just a pusher.
As for Magi standards, do they have any? There isn't a cat in hell's chance that Venturi flows 50m3 per hour out of a single return jet. Placing a filter in front of a pump as they and Desjoyeux do is really inefficient.

[jpadie]

so where does the 'pull' from the pool occur? just from a venturi effect by each skimmer?

my new pump placement will be below fractionally below the water line too. somewhere between 6-12 inches depending on the eventual dig out.

i've never believed the magiline claims about being able to recycle the water in 4 hours. the filters clog up whenever they are within 10m of a piece of dirt and the return flow slows to something an old man with prostatitis would be proud of. I like the polaris pressure robot that the fitter threw in though. it's been abused for fifteen years and I've rebuilt it a dozen times with scrap plastic and it soldiers gamely on.

[Teapot]

There isn't much pull on most pools at the mouth of the skimmer it's more spill over and push from the returns. As this spill over is concentrated at the mouth of the pipe work there is a strong pull, some pools have ridiculously large powerful pumps that could do damage should someone's body part be involved. Above the water line pumps have different impellers to self prime the system and these same pumps are universally used when positioned below the water line but all you really need is an impeller that pushes.
I have a non self priming pusher pump on my pool and correct flow to provide great filtration with minimal electrical usage.
Where this idea of trying to impress people with silly high flow rates comes from I can only guess at the marketing people because it is counter productive to good filtration. Slower flow equals better filtration catching roughly 4x more dirt etc.
It can save a lot of electricity, I say 90% saving to my customers guaranteed if the system is suitable as I have seen some horrible plumbing, can sometimes sort this out but not if it's concreted in obviously.

[jpadie]

Yup. I see.

I think with the magiline pools, or at least with mine, the suction effect is quite strong when the filters are clean. A significant vortex occurs in the skimmer areas.

A key problem with my pool is that there is little turbulence in the basin outside the immediate are of the skimmers. So the water doesn't seem to circulate and suspended particulates below the skimmer like stay unfiltered. I've always felt that if the bottom drain was connected to a filter that would improve things. But magiline assured me that this was not the case and the bottom drain was only ever used for emptying.

On a related note I'm not going with a variable speed pump as the prices seem very high. Experiments with a standard single speed pump (triple phase) and a cheap VFD suggest that this will work fine. And works out a 1250 cheaper than the quote from aquajulien. Have you ever tried or used a separate VFD to control a pool pump?

I suspect this will burn out every couple of years (the VFD not the pump). But given cost and availability that seems an acceptable cost.

[jpadie]

So coming back to the original question, it does look like I lose the return for the robot as that is part of the pump and will be on the suction side of the new pump. The pool is in a large concrete deck so it isn't practical to replumb. I'm adding the filter and pump in the section of plumbing that used to have the chlorinator. One 63mm pipe coming in to the chlorinator and three 50mm pipes leaving.

I think that means I also lose the side suction below the old pump placement.

So if I want to keep the robot do I have to leave space for a secondary pump and attach the robot directly to that?

[jpadie]

Just to avoid confusion, this is not the system that I have.

The pump is there but there is only a 50mm tube coming in to the impeller. There is no secondary pipe above.

There is a filter cartridge in the area next to the pump but it has no skimmer. In lieu there is a side entry about 60mm wide that pulls water through the filter from the outside and then through the large orifice at the bottom of the inside of the structure. There is no return in this area.

I will have to continue digging for a diagramme of the older type of units.

[Teapot]

Ok yes, I vaguely remember that earlier one but any photos would help. Not converted any of those, only the pictured ones