Building a swimming pool

[Neil.SuperGuide]

Hi Guys
I am just about to build a small swimming pool 3x8 meter
I got 2-3 offers but I am totally confuse.
Is there any tips anyone can give about the brand of pump to use and other tips ?
thanks

[frank1957]

hayward pumps are really reliable, I would also make your pool slightly bigger if possible we looked at 3x8 and ended going for 4x9 and it made a big difference

[JW]

If you wanna swim laps go 12x3.

[jingjoe]

I agree i just installed an 11by 4.4 fibreglass pool just the right size for laps.fibreglass only takes a week from install to swim..better on chemicals and takes the hassle out of a build

[huahin4ever]

Jingjoe: could you post a picture? Who build such pools in Hua Hin?

[jingjoe]

swimming pool fibreglass

another pool shot

phpKM8sxcAM.jpg (47.52 KiB) Viewed 1478 times

[brianks]

I would recommend a longer pool for sure. Makes a big difference if your planning on using the pool for exercise rather than just getting wet.

You asked about a pool pump. Purchase the Pentair variable speed pump. I have one on my new 4m x 14 meter pool and when pool completed on only added 500 baht to elect. bill. Its a computer controlled pump that will adjust its speed for any size pool. Mine runs at only 600 RPM and is very quiet. Much different that the noisy single speed pumps I had in my two pools in Hua Hin. Cost is 39,000 baht but when you factor in the savings in electricity will pay for itself in a year or two.

[PeteC]

I would recommend a longer pool for sure. Makes a big difference if your planning on using the pool for exercise rather than just getting wet.......

I really agree with that. Mine is 10 and I try to do 200 meters each morning. All I'm doing is turning around all the time and it gets frustrating. A 25 is really best but $$$ and space, space, space. Pete

[Nereus]

I would recommend a longer pool for sure. Makes a big difference if your planning on using the pool for exercise rather than just getting wet.

You asked about a pool pump. Purchase the Pentair variable speed pump. I have one on my new 4m x 14 meter pool and when pool completed on only added 500 baht to elect. bill. Its a computer controlled pump that will adjust its speed for any size pool. Mine runs at only 600 RPM and is very quiet. Much different that the noisy single speed pumps I had in my two pools in Hua Hin. Cost is 39,000 baht but when you factor in the savings in electricity will pay for itself in a year or two.

Where did you buy this pump? Does the price include a seperate program controller? Thanks.

[dozer]

http://swimmingpoolsthailand.com/en/pum ... iland.html

A friend of mine fitted a BADU EcoM3 3-speed pump to his pool, got it locally.

[brianks]

Pentair Pool variable speed pool pump can be purchased from Mr. Pool which is a Bangkok based company. Contact: sariya@peerapat.com as she is the president of the company. You cannot purchase a better pump! Google Pentair Pool Pumps and read the literature about it. Would show a picture but seems my shrunken image is still too large for this site.

This company was at the recent Architect 14 show in Mung Tong Thani, Challenger Hall and is a reputable company. There current price is 39,000 baht as shown at the show. Pump, computer and everything comes as one unit with a LCD display on the pump.

PM me with email address and I can send you pictures or any more information on it. I am sold on this pump as the pumps on my pools at my former houses cost about 1,500 baht/month for electricity and were noisy. My current pool is much larger at 4 x 14m than my former pools of 3 x 7m and 3.5 x 12m yet my electric bill is 1/3rd less because of the Pentair pump. We had the pump shipped to Surat Thani where we picked it up. Installed by a pool equipment installer in Puckett who also sold the pump but charged twice the price to his customers for it.

[PeteC]

Variable speed pool pumps are a whole new level of product I wasn't even aware existed. Hayward and I'm sure others seem to have gone down the same path. Pete

https://www.hayward-pool.com/ctg/In-Gro ... 4002_I.htm

[Nereus]

I am just in the process of writing up some info on them. I was also unaware that these type of motors were being used on pool pumps.

[brianks]

Here is the website for the Pentair Intelliflo-VS-SVRS variable speed pump.

http://www.pentairpool.com/products/pum ... mps-76.htm

It is NOT plastic.

[Nereus]

I post this as general interest for those interested. If you are not interested please ignore it and refrain from snide remarks. Thank you.
...........................................................................
An interesting use of modern technology. The pumps are using a new type pf electric motor known as: PMAC, or Permanent Magnet Alternating Current motor.

In a conventional AC induction electric motor there is a “stator”, the circular frame of the motor that is fitted with a slotted laminated core, in which the coil windings are wound and energised by the AC supply voltage. The coils are arranged to produce a magnetic field, either in a North –South alternate sequence in the case of a single phase motor, or a “rotating field” in the case of a 3 phase motor.

The “rotor” consists of a shaft on which is built up another laminated core, and in place of the windings as in the stator, the slots carry a cast in set of “rotor bars”, which are joined at each end and called a “squirrel cage”.

In operation the magnetic field produced by the stator is “induced” into the rotor bars, which, because of the way they are made, cause an opposing magnetic field to be produced that reacts with stator field in the well known “like poles repel—opposite poles attract”, and hence result in rotation of the rotor and shaft, and why it is called an “induction” motor.

It should be also understood that this type of motor is “asynchronous”, that is; it runs at a slightly lower speed than the theoretical speed that the number of poles and the supply frequency produce. This is called “slip” and can be thought of as the rotor trying to “catch up” with the stators magnetic field. In a single phase motor it is necessary to have a “starting winding”, or otherwise the rotor would just “lock up” and could not turn. The starting winding is only used for few milliseconds at switch on (about 75% of full speed), and is the “click” you may have heard as the motor starts up. The noise comes from a centrifugal switch that opens and disconnects the starting winding. (more modern motors are now using an electronic switch). 3 phase motors do not need a starting winding, or switch.

This type of motor is well proven and use understood technology, having been in use for decades. (even I understand how they work!)

Although a highly efficient method of converting energy, there are still some losses in the process. Depending on the application, the overall efficiency can be anywhere between 70% to around 90%. One considerable reason for some of these losses is referred to as I squared R, where the loss is seen as wasted heat. It is not feasible here to detail all of the causes, as there are many variables. Bearing friction and windage drag can also be considerable, especially in higher speed motors. The “slip” mentioned above is also considered a loss. A motor running at other than its designed load also loses efficiency.

Speed: The rotational speed of an AC induction motor is a function of the number of magnetic poles in the windings, and the frequency (Hz) of the AC supply. This means that the speed is relatively fixed (disregarding losses), except in the case of 2 speed motors that are wound with 2 sets of windings, and in that case still fixed at whatever the 2 speeds are wound for.

Conventional AC pool pump motors are usually single speed, 2 pole motors. With a 50 Hz supply the synchronous speed is 3,000 rpm, and the actual speed after taking into account “slip”, is around 2,850 rpm.

NOTE: The frequency should be taken into account when looking at pump output graphs on the Internet, as most of them are calculated with the USA supply frequency of 60 Hz.

The end result of all of this is that it very likely that your pool pump is either way over capacity for the required flow, or is not big enough leading to longer running time to achieve the desired result. As ALL pool installations are different in regards to actual flow required, energy is wasted and paid for with a bigger electric bill each month.

MPAC Motors: With the introduction of this type of motor there is now the option of setting a running speed most suited to each individual pool system.

Variable speed drives have been in use in industry for many years. The biggest percentage of them use DC motors, although there have been some specialized and expensive AC motors, mostly used in the textile industry.
With modern electronics, mostly using silicon controlled rectifiers (SCR), or thyristors, very precise speed control is achievable. However, a DC motor requires a lot of maintence, and the conversion from AC has a very poor power factor, leading to poor efficiency.

The modern trend is to variable frequency AC drives; VFD, where an electronic controller using pulse width modulation, PWM, is used to drive an AC induction motor. These drives are mostly made for 3 phase motors, although some are now appearing for single phase. The efficiency is good and a standard AC motor can be used for most applications.

The more recent development of PMAC motors is what this is about. The motor still has a stator with coil windings, but the rotor now has permanent magnets in place of the older style “squirrel cage”, which eliminates the need for the stator windings to “induce” a magnetic field into the rotor. The other BIG difference is that a “drive” is required, which is similar to the electronic controller used with the VFD above. One notable difference is that the “drive” is built into the frame of the motor. The motor also runs at synchronous speed, so an accurate output of the pump can be calculated.

Rather than try and write up a deeper explanation I will link to a very good description on the Internet. Also, a link to just how and why, a variable speed pump is able save on power use.

PMAC Motor: Although this motor is designed for a hybrid car, it shows a very clear description.

http://www.johnwmorehead.com/nissan-lea ... -ac-motor/

How a PMAC motor can save power usage: This article has a bit of material that is not applicable in Thailand, but it has a very good and clear description of how the concept saves power. It also makes a comment concerning the use of pipe fittings that I have complained about previously!

http://www.nrel.gov/docs/fy12osti/54242.pdf

Like all things, you do not get something for nothing! It is still necessary to “turn over” the complete volume of water in the pool, preferably twice, every 24 hours.
So, to achieve this the pump will have to run for a much longer period, albeit it at a much lower power consumption.

Running at a much lower speed the life of the windings and bearings will be much greater, but the main reason is it will run much cooler, and heat is a destroyer of insulation.

(PMAC motor losses (the inverse of efficiency) are 15% to 20% lower than conventional induction motors)

To get sufficient flow for cleaning it will be necessary to run the pump at a much higher speed for the time that it takes to vacuum the system. If you want to use a “robot” type of pool cleaner, the same will apply, as the low flow rate will not operate these devices. If you have a spa section, the same will apply, or you will need a separate pump. (which most have in any case)

With the well known “iffy” electrical supply in this country, you could have problems with the electronics, unless you can provide some type of AC filtering device. I believe that some of the more up to date chlorinators are prone to failure for this reason.

I doubt very much if any, even the supplier, has the facilities, or the technical expertise, to repair these motors in Thailand. If it fails I would suggest that you would be up for a complete new motor. The pump end of it should not be any different to existing pumps. But only time will tell about that, and I hope that it does not become a problem.
I notice that the frame type is T.E.F.C, which is something existing pumps are not, and also something else that I have commented on previously. All pool pumps should be of this frame type.

To get the full advantage of this pump, and still maintain the condition of the pool, some experimenting with run times and pump speed will be required.