Pump just died, panic mode engaged.

[Desiato]

I've read that higher horse power on a single speed pump is a bad idea as you are just putting extra strain/pressure on your filter and pipes and could lead to problems. One site had my 1hp pump slightly underpowered for my pool but the jump to 1.5hp was too big. I don't see much talk about pump sizing when it comes to VS pumps, just that they are quiet because they run at slower speeds and are more expensive. What I'm really trying to find out is, for my pool (which doesn't have any extras like hot tub/slides) what size VS pump should I be looking at? If I go too big do I run the risk of leaks because I'm trying to push too much water through my filter which is only designed for a 1hp pump? It's a balance between hp and $ but I think there are other considerations I need to take into account and I don't want to make a mistake by not finding out what they are and regretting it later.

 

[Bperry]

I've read that higher horse power on a single speed pump is a bad idea as you are just putting extra strain/pressure on your filter and pipes and could lead to problems. One site had my 1hp pump slightly underpowered for my pool but the jump to 1.5hp was too big. I don't see much talk about pump sizing when it comes to VS pumps, just that they are quiet because they run at slower speeds and are more expensive. What I'm really trying to find out is, for my pool (which doesn't have any extras like hot tub/slides) what size VS pump should I be looking at? If I go too big do I run the risk of leaks because I'm trying to push too much water through my filter which is only designed for a 1hp pump? It's a balance between hp and $ but I think there are other considerations I need to take into account and I don't want to make a mistake by not finding out what they are and regretting it later.

Slower speed = lower pressure so extra unused horsepower doesn’t matter. All those question go away in that case. I don’t see any reason to get a larger pump than needed, but some people are uber-sensitive to electric costs.

 

[Desiato]

This guy recommends that for 1.5" pipes (which mine is), it's probably best not to go over 2hp. He likes the Hayward TriStar VS SP3202VSP which is a 1.85hp but his video is 4 years old and looking on the Spanish Haywood site the 1.85hp is no more, mainly 1.5hp & 2.0hp models. I guess either of them would be fine for my basic needs and as you say, the 1.5hp should be cheaper but the 2hp could cover its additional costs in an extra year or so? Time to get the calculator and spreadsheet out. I did say at the start that €2k was too much of a stretch but I'm coming round to the idea if it can pay for itself in cheaper electricity bills in 5/6 years or so.

Anyone familiar with these models? Of the four pumps, the K-Flo VSTD says suitable up to 80m3 and mine is 67.75m3, is that the best way to choose a model or is there a more important factor I should consider? (apart from the price).

EDIT It looks like Hayward only do single speed 3 phase pumps. That would suggest that a variable speed pump that has a 3 phase power supply is not a viable option. Is that why VFD's exist, to fill that gap?

​

 

[Desiato]

There are other VS motors out there that you may be able utilize, or a complete new VS pump and motor package.

This thread seems to be dying, I think my confusion and non stop talking early on has scared people away so I'll try and keep it short.

As I have a 3 phase supply I've been looking for a 3 phase variable speed pump and found it almost impossible to find. I search through the specs of Hayward pumps and all the VS pumps are single phase, is there a reason for this?

Your suggestion of getting a 3 phase pump and adding a VFD to vary the speed would seem to be the only option.

I'm also looking into surge protection, as in, do I have any? My friendly electrician will tell me.

I made another mistake earlier, I said my pipes were 2", they are not, they are 1.5".

1.5" pipes = 2HP max power (from video linked above) so any recommendations for reliable single speed pumps? (or anyone know of a 3 phase VS pump?)

 

[Bperry]

This thread seems to be dying, I think my confusion and non stop talking early on has scared people away so I'll try and keep it short.

As I have a 3 phase supply I've been looking for a 3 phase variable speed pump and found it almost impossible to find. I search through the specs of Hayward pumps and all the VS pumps are single phase, is there a reason for this?

Your suggestion of getting a 3 phase pump and adding a VFD to vary the speed would seem to be the only option.

I'm also looking into surge protection, as in, do I have any? My friendly electrician will tell me.

I made another mistake earlier, I said my pipes were 2", they are not, they are 1.5".

1.5" pipes = 2HP max power (from video linked above) so any recommendations for reliable single speed pumps? (or anyone know of a 3 phase VS pump?)

You can use a phase converter to get from 3 phase to single phase, then you can use any pump you want.

 

[Desiato]

You can use a phase converter to get from 3 phase to single phase, then you can use any pump you want.

Thank you Bperry, talk about getting straight to the point. That's all I needed to know. You're a legend.

EDIT.

Guess I jumped the gun a little bit there, a quick google for prices for a "3 phase converter" on Amazon brings up "Variable frequency drive".

I thought the VFD was only needed to make a single speed pump variable speed? Why would I install a VFD and then buy a VS pump when they are 3 times the price?

 

[mknauss]

recommends that for 1.5" pipes (which mine is), it's probably best not to go over 2hp.

Does not matter with a Variable Speed (aka Variable HP) motor. You limit the rpm to a lower level.

 

[Bperry]

Thank you Bperry, talk about getting straight to the point. That's all I needed to know. You're a legend.

EDIT.

Guess I jumped the gun a little bit there, a quick google for prices for a "3 phase converter" on Amazon brings up "Variable frequency drive".

I thought the VFD was only needed to make a single speed pump variable speed? Why would I install a VFD and then buy a VS pump when they are 3 times the price?

Not the same thing (they may call it a single phase transformer?) If cost is your issue, then might not make sense anyway. I read you can convert 3 phase to single for phase by just using one of the phases and a neutral but thats just for dumb motors, etc without sensitive electronics. Probably best for an electrician to handle.

Maybe a VFD with a single speed motor is your most economical option.

 

[Darin]

Since you are on three phase power you will need to find a motor that can accept the input.
Here in the USA we don't really have three phase to house (unless you have a really, really big house), only single phase. Anyway since you are Spain all your local dealers will have the proper systems for your input voltage. Just go with the VS and you will be happy and save money.

 

[Darin]

You can use a phase converter to get from 3 phase to single phase, then you can use any pump you want.

Phase converters are old school, dare i say obsolete. VFD's are cheap and readily available.

 

[Darin]

I can now say with utmost confidence that what you have said is completely true, you do not need a VFD if you are changing from a single speed to a variable speed.

Option 1
If you were to replace your motor with a like motor you could install a VFD and have variable speed control,
Option 2
or you could replace your motor with an integrated motor/controller for VS with you needed input voltage to fit your pump
Option 3
Purchase a complete Pump with motor that has an integrated controller for VS for your needed input.

Three options and how much to spend to save later.

 

[Bperry]

Option 1
If you were to replace your motor with a like motor you could install a VFD and have variable speed control,
Option 2
or you could replace your motor with an integrated motor/controller for VS with you needed input voltage to fit your pump
Option 3
Purchase a complete Pump with motor that has an integrated controller for VS for your needed input.

Three options and how much to spend to save later.

I think is issue is that #2 and #3 are hard to find in Spain.

 

[Darin]

I would think V-Green would make motors for the European market.

 

[Desiato]

Since you are on three phase power you will need to find a motor that can accept the input.
Here in the USA we don't really have three phase to house (unless you have a really, really big house), only single phase. Anyway since you are Spain all your local dealers will have the proper systems for your input voltage. Just go with the VS and you will be happy and save money.

Three phase supply to larger houses are quite common here, not sure why. All the VS pumps I can find are single phase and all the 3 phase pumps I can find are single speed. I'll admit I haven't spent days looking but this is what I've seen with a few hours searching the web. My electricity bills are stupidly high so going for a VS pump would help but as I can't find any 3 phase ones, option 1, single speed pump +VFD ticks the right boxes and is cheaper than a VS pump.

I'm seeing pump and motor spoken about as if they are two separate units. For me a pump has a motor and if it is a VS pump, comes with a controller to change the speeds. That's as far as my knowledge goes.

Thanks for the replies Darin and Bperry, I've got a builder friend who install pools looking to see what he can get for me and a friendly electrician trying to fix the pump and if that fails, we'll talk about single speed 3 phase pumps + VFD + surge protection. But for now, I'm still stirring in the bleach with the broom.

 

[Desiato]

I would think V-Green would make motors for the European market.

A google search for Vgreen and "Bomba Piscina €" finds nada.

 

[Desiato]

Most of the forum posts I've read about VFD's talk about using the VFD to change from 3 phase to single phase or vice versa. This got me thinking, do I go:

a) 3 phase supply > 3 phase into VFD, 3 phase out of VFD > 3 phase single speed pump

b) 3 phase supply > 3 phase into VFD, mono phase out of VFD > mono phase single speed pump

I then found this.

Post 4 in this thread from 2013 says "You always need an inverter duty motor when using a VFD or the motor and drive will not last very long. I don't believe you can use a three phase VFD on a single phase motor since the phasing is not correct. Single phase is split-phase, 180 degrees apart, while two arms of a three phase supply is 120 degrees apart. Plus in a three phase VFD, all three arms must be balanced or it will fry the VFD. Plus, I doubt a $150 VFD is very high quality and would last that long".

Inverter duty motor + VFD, that's new? Can't use a 3 phase VFD with a single phase motor? Are the $150 VFD's lasting very long?

Just so much to learn.

 

[Darin]

No, the above text is gibberish.

Pools motors are small and static is not a problem. Some VFD's are only for taking single phase input to three phase output. some take single or three phase input to three phase output, some take three phase input to three phase output. You need one of the last two. They are cheap.
You need a AC motor like you have and a VFD ~$150 that is it. My old TECO VFD was about $200 five years ago and it is just fine. VFD's are getting cheaper every year.

Is your three phase input 220V or 400V? Here is a cheap one for input three phase 220V, output three phase 220V.

Amazon.com

 

[Desiato]

I must admit, I've been reading the headline and not the details and just like in the VFD you linked, it says "single to 3 phase" in the headline but "Input：220VAC(+/-5%) 1 or 3phase（for single-phase input, just connect the input wire to the R and S terminals） .Output：3phase 220v. Frequency：0-50hz/60hz. 0-400hz" In the details.

I said something earlier about "why would I buy a VS pump + VFD if I can buy a SSP + VFD and achieve the same outcome for considerably less $?". Well, talking to my electrician yesterday, he wasn't very keen on installing a VFD for my 3 phase single speed pump because "the pump wasn't designed to be run at slower speeds". I initially dismissed this (in my head) as some of you guys have been doing this for years but then I read that VS pumps are built differently, with permanent magnet motors. Hmm, so maybe just reducing the power has drawbacks? Why would they design a completely new motor if all they had to do was add a box of tricks that reduced the power?

So I'm a little stuck now, I want to add a VFD but need to convince my electrician that it is safe to do for a single speed pump. Anyone got anything I can point him at apart from "well, it's working for me". No offence to those people, it may be working fine for years but it may also be slowly killing your pumps, just as an example.


Not related but I decided to add up how many hours I run my pump a year and came to an interesting conclusion. It's 8 years now since finding this site and I've got the chemistry ticking along nicely without any unexpected algae outbreaks. I run my pump 4 hours at night during the summer months, 3 during spring and fall, 2 in the cooler months and 1 during winter (no need to close the pool in winter, haven't seen snow here for decades) and it's been just fine. That adds up to roughly 1000 hours a year. Add on 52 for vacuuming an hour a week and 48 for backwashing and occasional running when the pool is full of kids and I get 1100 hours a year.

The pump pulls roughly 900 watts according to my monitor, (I also recorded 20Kw when running for 24 hours so that also ties up) so that's 1000 kw/h and at a cheap rate of 11.11 cents an hour my bill is €110 + 10% vat = €121 a year.

A VS pump would double the number of hours running and halve the cost (based on estimates I've seen here) so a saving of €60 euros a year. If I saw a 75% saving that would be €90 a year.

This would still make adding a VFD a viable option as I can see I would get that money back in a few years but upgrading to a VS pump (without a SWCG), can't see the financial benefit there. If I went down the road of SWCG and ran the pump 12/24 hours a day, sure, I can see how that would work but for me and how I've been managing my pool, I don't need to run my pump that much.

Anything I've got glaringly wrong there?

 

[Bperry]

I must admit, I've been reading the headline and not the details and just like in the VFD you linked, it says "single to 3 phase" in the headline but "Input：220VAC(+/-5%) 1 or 3phase（for single-phase input, just connect the input wire to the R and S terminals） .Output：3phase 220v. Frequency：0-50hz/60hz. 0-400hz" In the details.

I said something earlier about "why would I buy a VS pump + VFD if I can buy a SSP + VFD and achieve the same outcome for considerably less $?". Well, talking to my electrician yesterday, he wasn't very keen on installing a VFD for my 3 phase single speed pump because "the pump wasn't designed to be run at slower speeds". I initially dismissed this (in my head) as some of you guys have been doing this for years but then I read that VS pumps are built differently, with permanent magnet motors. Hmm, so maybe just reducing the power has drawbacks? Why would they design a completely new motor if all they had to do was add a box of tricks that reduced the power?

So I'm a little stuck now, I want to add a VFD but need to convince my electrician that it is safe to do for a single speed pump. Anyone got anything I can point him at apart from "well, it's working for me". No offence to those people, it may be working fine for years but it may also be slowly killing your pumps, just as an example.


Not related but I decided to add up how many hours I run my pump a year and came to an interesting conclusion. It's 8 years now since finding this site and I've got the chemistry ticking along nicely without any unexpected algae outbreaks. I run my pump 4 hours at night during the summer months, 3 during spring and fall, 2 in the cooler months and 1 during winter (no need to close the pool in winter, haven't seen snow here for decades) and it's been just fine. That adds up to roughly 1000 hours a year. Add on 52 for vacuuming an hour a week and 48 for backwashing and occasional running when the pool is full of kids and I get 1100 hours a year.

The pump pulls roughly 900 watts according to my monitor, (I also recorded 20Kw when running for 24 hours so that also ties up) so that's 1000 kw/h and at a cheap rate of 11.11 cents an hour my bill is €110 + 10% vat = €121 a year.

A VS pump would double the number of hours running and halve the cost (based on estimates I've seen here) so a saving of €60 euros a year. If I saw a 75% saving that would be €90 a year.

This would still make adding a VFD a viable option as I can see I would get that money back in a few years but upgrading to a VS pump (without a SWCG), can't see the financial benefit there. If I went down the road of SWCG and ran the pump 12/24 hours a day, sure, I can see how that would work but for me and how I've been managing my pool, I don't need to run my pump that much.

Anything I've got glaringly wrong there?

You don’t have to run a variable speed pump longer. It’s just an option. With a single speed pump you are stuck running it at high speed for however long it takes to skim the water and mix chlorine.

The variable speed pump also isn’t a linear power savings in that you can run it at half speed for the same amount of time and results in 50% less cost. (It’s supposed to be more than 50% savings.) The slower it runs, the power draw drops off non-linearly.

All that said, I think you’re thinking about it too much. If you don’t mind the single speed and money is kinda tight, stick with it. I was thrilled about the noise reduction of the variable speed pump running so slow I can’t hear it anymore and the cost was worth it just for that.

 

[Desiato]

You don’t have to run a variable speed pump longer. It’s just an option.

That's not strictly true though is it? If I run my single speed pump for 4 hours at 2850 rpm to get a single turn over, I'd need to run a VS pump at 1425rpm for 8 hours to achieve the same, no?

The variable speed pump also isn’t a linear power savings in that you can run it at half speed for the same amount of time and results in 50% less cost. (It’s supposed to be more than 50% savings.) The slower it runs, the power draw drops off non-linearly.

Agreed, that's why I gave two savings of 50% and 75% to see what that monitory saving would look like. I also said double the time for half the cost as that's what I've been reading here.

All that said, I think you’re thinking about it too much.

Am I though? If I had rushed out and bought the first VS pump I could find (any VS pump it would seem), I'd have to return it because it was single phase and I have 3 phase. I've read so much about how much money you will save off your electricity bill by going variable speed and only this morning did I calculate exactly what savings I'd be looking at and it's not that much. This thread has introduced me to VFD's and given me a route into reducing my bills long term by reducing the power but I need to get the electrician onboard as his experience with VFD's is with larger machine pumps and he uses them to smooth out the initial surge when powering them on. He has reservations about using them for a pump that wasn't designed to have it's power altered so you could call that overthinking it but I prefer to call it being thorough and it's saved me many times in the past from costly mistakes. That said, after doing my calculations, I won't be seeing any big savings going the VS pump route but I can see a VFD happening when both my electrician and I look a bit more at what options are available and what pumps are better suited to power reductions. Funnily enough, a whisper quiet pump is close to bottom of my list of 'must haves' so clearly we all have different USP's.

Thanks for your replies though, much appreciated. At least your only contribution wasn't to ask if I had a broom!

PS, The electrician has repaired the pump with a new bearing but it's making some interesting, how do I describe it, sonic reverberation type noises so at least I can put the broom away but will take this breathing space to work out the best upgrade solution.