Possible to reduce spa spillover without changing pump speed?

[robbief00]

My pump/filter splits to six pool returns and one spa return. There is no valve to control the spa return. I would like to reduce the volume of water on my spillover from a loud waterfall to a slow/quiet trickle without reducing the pump speed.

My thought was to just reduce the eyeball return in the spa from a 1" to a smaller 3/4" or 1/2" orifice. I don't think this will affect pump efficiency/filter pressure much (if any) since more water will just divert to the pool returns. I also don't think filtering and chlorine levels in the spa will be affected much since it is all a connected system.

Is there anything else that I am not thinking of that may cause harm by changing the spa eyeball return?

 

[JasonLion]

Using a smaller return fitting on the spa will reduce the amount of water flowing into the spa. For even more flexibility you could install a valve on that line so the flow rate can be changed any time. There may be a tiny effect on the filter pressure, but it won't cause any problems.

 

[mas985]

There is no valve to control the spa return.

Then how do you put the spa into spa only mode so you can heat it?

 

[robbief00]

Then how do you put the spa into spa only mode so you can heat it?

Coming out of the filter and heater, there is an actuator valve. This valve switches between 1) pool returns and single spa return that creates the spillover and 2) all spa jets (for heating). When in mode 1) there is no valve on the single spa return so I cannot adjust the spillover flow.

 

[mas985]

The eyeball might help some but if you really want more control, you should have a valve there. Is there enough room to add a valve?

 

[robbief00]

I could probably add a manual valve there eventually. I am just trying to avoid cutting into my brand new plumbing and voiding any warranty I have with my builder. I will try the smaller eyeball first.

 

[robbief00]

I just thought of another possible solution. I also have an actuator on the suction side that switches between pool drain/skimmers and spa drain. The spa drain is normally closed in pool mode but I might be able to adjust it so the spa drain is slightly open to reduce the spillway amount. I think this could get dangerous though if the spa drains more water than is being put back in with the return.

 

[Richard320]

I just thought of another possible solution. I also have an actuator on the suction side that switches between pool drain/skimmers and spa drain. The spa drain is normally closed in pool mode but I might be able to adjust it so the spa drain is slightly open to reduce the spillway amount. I think this could get dangerous though if the spa drains more water than is being put back in with the return.

Bingo! We have a winner.

I tried balancing the input and output on my spa. It was hard to match and someone pointed out the risk. What if the skimmer basket gets restricted with leaves? Where will the pump draw from? The spa, that's where, because it has less resistance. So then it starts drawing more from the spa than it returns. And then it starts sucking air and loses prime. And you've smoked your pump.

 

[mas985]

I could probably add a manual valve there eventually. I am just trying to avoid cutting into my brand new plumbing and voiding any warranty I have with my builder. I will try the smaller eyeball first.

The builder should have put in a valve. That is what is normally done. Show him this Jandy pic: