Variable Speed Demand Water Pumps

[RAH]

I am thinking of swapping out my stock Shurflow water pump for a Flojet VSD – the 3.7 gpm model. Reason I’d like to try the VSD pump is to get a quieter pump (hopefully). There is one instruction that makes me question if the VSD will work. “Note: When using a power supply or converter, a battery must be in the circuit for proper operation.” When I’m connected to shore power I normally have the “battery disconnect” switch to “store” so I don’t over-charge the batteries. With that, haven’t I taken the battery out of the circuit? I guess I could always leave the battery in “use” but it wouldn’t make sense (to me) to sacrifice a battery just for that.

I am struggling with why the VSD pumps require a battery in the circuit, whereas other water pumps do not. Is anyone out there using a VSD water pump? Any thoughts on if the VSD pump will work, or if I should even give it a try?

Thanks

[Bigventure]

Are you sure you don't have a varable speed now? My 2011 came with one from new.

[RAH]

I don't think I have a variable speed now - it doesn't say VSD anywhere. What model do you have in your 2011 - Shurflow or Flojet?

[ROBERTSUNRUS]

Originally Posted by RAH

I am thinking of swapping out my stock Shurflow water pump for a Flojet VSD – the 3.7 gpm model. Reason I’d like to try the VSD pump is to get a quieter pump (hopefully). There is one instruction that makes me question if the VSD will work. “Note: When using a power supply or converter, a battery must be in the circuit for proper operation.” When I’m connected to shore power I normally have the “battery disconnect” switch to “store” so I don’t over-charge the batteries. With that, haven’t I taken the battery out of the circuit? I guess I could always leave the battery in “use” but it wouldn’t make sense (to me) to sacrifice a battery just for that.

I am struggling with why the VSD pumps require a battery in the circuit, whereas other water pumps do not. Is anyone out there using a VSD water pump? Any thoughts on if the VSD pump will work, or if I should even give it a try?

Thanks

Hi, your trailer may be different than mine, but when mine is plugged into shore power it automatically bypasses the store mode.

[daveswenson]

The store mode isolates the batteries from the 12 volt system. The converter still powers DC but the batteries do not charge or provide power.

[idroba]

I believe that AS uses the variable speed Sure Flow pump as standard, at least it was standard on the 2013 FC series and my 2014 has one. I am not overly impressed with it but there are far more 90 degree elbows in the intake and outlet distribution piping that AS builds than are necessary. I think my system has way too much friction in it to work properly. That, however is a guess on my part. So, my thoughts are that the piping system is more of a problem than the pump is.

You ask why would a battery be required with the Flo Jet system according to the instructions... I believe it is because many SOB's have a very poor electrical converter charger capacity and they would not supply enough power to run the variable speed pump properly. However, the AS converter/charger is a 55 amp version and has plenty of capacity even without the battery in the system. So, if you did change the pump out I don't think you need to worry about that specification.

If you really want to protect and save your batteries I would recommend you change out the guts of your AS original converter/charger for a PD 46xx 3 stage converter charger for about $200. Then you never have to worry about any long term overcharge or problems and can leave your USE/Store switch on USE all the time.

[Castaway]

We have a variable speed pump in our 2012 25'FC, you can hear it pick up speed when you increase the water volume.


Gary

[dkottum]

RAH, I keep the switch in the store mode on shore power as well for the same reason. Our 2012 FC has a variable speed pump.

I wonder why the batteries would have to be in the circuit for the Flojet VSD pump operation. Perhaps a converter can supply the voltage but not the amperage requirement of that pump.

It seems unusual though to have shore electric without shore water supply available.

doug k

[jdalrymple]

My 09 has the variable speed pump from the factory.

It runs fine with the the battery switched in use or store.

It is not a quieter pump, by any means.

The most I have done to quieten things down is to add an accumulator tank.

I did this with the full understanding that the factory does not recommend an accumulator tank with variable speed pumps.

With the tank, the water flow is much more even with no surges and the pump is noticeably quieter.


Regards,

JD

[jaygood31]

Voltage from the converter is not "clean" DC. With the battery in the circuit the peaks and valleys are filtered out by the battery. If you run the pump direct from the converter you may damage the pump over time.

Jay.

[tkasten]

I've installed a Flojet Var. 3.7 in my 65 Safari and love it. It provides water flow like our house on full and is very quiet. When running lower flows we can't even hear it run.

[jdalrymple]

Originally Posted by jaygood31

Voltage from the converter is not "clean" DC. With the battery in the circuit the peaks and valleys are filtered out by the battery. If you run the pump direct from the converter you may damage the pump over time.

Jay.

I agree it is not the most filtered power source, but my isn't bad enough to ruin a pump.


Regards,

JD

[Bigventure]

Originally Posted by RAH

I don't think I have a variable speed now - it doesn't say VSD anywhere. What model do you have in your 2011 - Shurflow or Flojet?

I can't make it all out because its under the oven on my unit. It's a Sureflow Start sense 4900-???

[RAH]

Thanks for the advice everyone. I will be putting the Flojet VSD 3.7 gpm in tomorrow. Somewhere along the line my next projects will include surge protection, maybe later changing the converter/charger as idroba suggested in #6 above.

[Bruce B]

I am sure you have made up your mind now but I will add my experience with the VSD pumps. We went through three of them in about 5 years on our sailboat before I gave up.
They are not any quieter than the conventional type. I finally switched to a Jabsco 6 valve monster pump that is now 4 years old and is working just fine.
Also our little 16' Serenity has not got a VST pump. They may use the VST in larger units? I hope you do better than We did.
Bruce

[RAH]

Thanks for sharing your experience Bruce. I haven't so much "made up my mind" as decided to "give it a try". I installed the FJ VSD pump this morning - so far so good and it seems quieter (just perception?) But as you point out time will tell. The install instructions on the VSD pump have made me think about power a bit more - my next purchase will be a surge/voltage protector from Progressive Industries. It doesn't make much sense for me to think of that relative to "protecting" a water pump that cost $194 given the cost of all of the other electronics that I have including solar. But better late than never. Thanks again.

[Bigventure]

This has happened to me. You pull into a campground and hook up. Your surge guard will not let power pass because it says the polarity is reversed.

At that point your dead. If you have a portable unit you can just unplug it and not use it. Essenually bypassing it. If its built in you will have no power at all and cannot read the screen on it if its buried under a cabnet.

Reverse polarity is not good for flat screen TVs and AC but you can still use a toaster, fridge and charge the batterys.

[daveswenson]

Originally Posted by Bigventure

This has happened to me. You pull into a campground and hook up. Your surge guard will not let power pass because it says the polarity is reversed.

At that point your dead. If you have a portable unit you can just unplug it and not use it. Essenually bypassing it. If its built in you will have no power at all and cannot read the screen on it if its buried under a cabnet.

Reverse polarity is not good for flat screen TVs and AC but you can still use a toaster, fridge and charge the batterys.

You're not dead. You just plug into the front outlet that bypasses the surge unit.

Buried under a cabinet? How hard is it to open a door?

I guess that's why they make both built in or portable so you can make a choice.


I thought this thread was about water pumps.