[david jones]

So, I'm looking to upgrade my portable and I'm researching all the odvious places, Alltec, Ashbys, Prochem etc and I seem to be finding contradictions on what is the best formation of vac motors.

Ashby's make a big point about parallel motors not increasing vacuum strength and say that in-series is the way to go, yet Alltec make the point that vac motors positioned in parallel give greater air-flow, and that this is the best configuration.

I have to say I have used both configurations in the past and I'm not sure if there is much differance!

I'd love to hear if anyone else has any more knowledge on the subject and which configuration is preferred, if any!

[Ken Wainwright]

For a twin vac porty.

If you are working with 15ft of vac hose, series, IMO, will be better.

If you are working with 25 of vac hose,  IMO, they will be about equal.

If you are working with >25ft of hose, IMO parallel will be better.

Interestingly, if you search for the new Ninja in the States, they have now changed to parallel vacs

Parallel vacs, everything else being equal, will last longer. The number one vac with a series set up always goes down first, and has perhaps about half the life of number two.

Safe and happy cleaning
The Ken

[Adam Fearnley]

That is an interesting point ken and certainly the case with me.  Is number 1 vac the one nearest the exhaust? why does this one fail more often?

[Ken Wainwright]

The number one vac is the one that connects to the waste tank. Because it is being "pulled" by the second vac, it is always running at close to maximum rpm, which is why it has a lesser life expectancy.

[david jones]

That is interesting that the ninjas in America are parallel. Ive heard in-series vac 1 have shorter lives before so that's something to think about. I use either 25ft or 50ft  hose lengths so I guess parallel set up is looking the way to go.

[Simon@arenaclean]

My first twin vac was a cleancare machine that had the vacs in series. In two years I replaced 4 vac motors. The lads at Alltec finally convinced me to buy their Alltec pro parallel machine that had two pipes in the tank. It was three years before I lost a vac and it was my fault

Simon

[Jim_77]

It doesn't matter which way round you organise two vacuum motors... you've still only got two electric vac motors!

2 vacs in series gives good lift but poor airflow.  2 in parallel gives better airflow but lacks lift.  Take your choice

[Colin Day]

It doesn't matter which way round you organise two vacuum motors... you've still only got two electric vac motors!

2 vacs in series gives good lift but poor airflow.  2 in parallel gives better airflow but lacks lift.  Take your choice

I always find Jim's answer on this subject very informative but Jim, which would "You" prefer, better lift or better airflow?

I have an Alltec with the 3 motors in parallel which is of course, Amtec's recommended configuration.

[Karl Wildey]

Airlift is good for upholstery cleaning, not so good for carpets
airflow is good for carpet cleaning, not so good on upholstery.

got to be airflow,

Alltec use a box system that is good for airflow and airlift

[Jim_77]

I prefer better lift AND airflow which is why I got a TM

But if forced to make a choice, I would opt for airflow.

Airflow without quite enough lift is a lot better than loads of lift and not enough airflow.

But really you can do the same job with a 2-vac porty whichever way around it is.