Is it normal to be able to feel the suction from a channel drain?

[Cluckr7]

We heated our spa for the first time today and I noticed that I could feel more suction that I expected when putting my foot over the middle of the channel drain (the part over where the pipe enters). It’s much stronger of a suction than I expected...still able to lift my foot very easily but I expected to not be able to feel any discernible suction at all with a channel drain. Is this typical?

Also, I looked back at pictures and it seems the PB used only a single PVC pipe underneath the channel drain. That is, he didn’t split it into two PVC pipes. Does this seem right? I know with normal drains you need the pipe to split into two drains at least three feet apart but not sure what is safe or typical with a channel drain.

Pictures attached.

 

[Cluckr7]

I will add that it’s the same design for my main drain. However for my waterfeature’s sidewall drain, there is a channel drain but for some reason the PB used two parallel PVC suction pipes behind the channel drain. Not sure why the different approaches.

 

[ajw22]

The channel drain is VGBA compliant and wide enough that a person cannot block the entire drain and get entrapped. The length of the channel drain accomplishes the same thing as two suction ports separated by 3 feet.

 

[Jimrahbe]

7,

You will just never be able to feel any real suction at a main drain(s).. This is just normal..

In most cases, having main drain is almost a waste of space.. We recommend having your skimmers wide open and your main drain only open about 5 or 10% just to keep the lines sanitized..

Thanks,

Jim R.

 

[Cluckr7]

Thanks for the quick responses.

For clarity Jim, I was actually concerned that I was feeling TOO MUCH suction from my spa channel drain. When I put my foot over the middle right above where the single pipe enters the channel, I can feel a pretty strong pull. Made me nervous with kids and long hair.

 

[Jimrahbe]

7,

I'm surprised... I have three pools, and although none of them have a channel drain, two of them only have single drain and I can't feel any suction at all.. You must have much larger pipes and a big pump than I have..

Let's see what @mas985 has to say as he is our flow dynamics kind of guy...

Thanks,

Jim R.

 

[Cluckr7]

A little extra info - I think my drain might be this or a similar model: AquaStar 32" Channel Drain with 3 Port Sump/Flat Grate Anti-entrapment Suction Outlet Cover (VGB Series) | White | 32CDFL101

Note that I don’t have an actual part number, I am just basing it on appearance.

I was reading the manual for this and it looks like it has connections for up to three pipes though I believe my PB only used the center one. I’ll need to get a better look next time - I only got a quick glimpse while holding my breathe in kind of bad lighting.

 

[JamesW]

Is that the only suction with a 2.7 hp VS pump at full speed?

Even if it is code compliant to just have one, I would have used at least two separate suctions for a 2.7 hp pump.

 

[Cluckr7]

That’s correct just one for the spa.

The pool has two skimmers and the drain.