Masterdoc 9420 Tuning

[claudiojr]

I've got a masterdoc 9420 wich i've been using with only one pump for about 2 years. Now i need it to work with 2 pumps, so i've bought another hydrofoamer. It seems to be impossible to tune the skimmer with both hydrofoamers working. I've been trying for almost 3 weeks with no success. Is there a "trick" to make it work? What should i do/try?:headwalls:

 

[shawnz28]

Are you using the shorter standpipe now you are running two pumps to lower the water level inside the skimmer?

 

[claudiojr]

Hi Shawn,

Yes i am using the shorter pipe, but foam level is too low in the skimmer, below the cup.

 

[rvitko]

Are both pumps running and are both correct 9420 and not one 9420 and one 9410? Have you checked that the needlewheels are the same? For 60Hz the needlewheels should have 2.5 rows, the 3rd row the needles are half length.

 

[Macca_75]

Separate Question, but is that level of water about correct? I have a single pump on a 9420 and run it much more shallow (top 1/2 of the pump is exposed). I've never really been sure about the depth and can't find a good photo of one running.

Thanks

 

[rvitko]

The depth can vary and is also a form of adjustment, but usually a higher water level is more likely to foam over, not underfoam, the skimmer pumps don't have to work as hard as the static water level is much higher, the skimmer is already that much more full of water. I generally would have 2/3rds of the pump submerged at a minimum and the water level can be as much as a few inches over the pumps.

 

[Macca_75]

Cheers