Let start by saying that this page has been great for me as a new 1st time pool owner. We moved into our house last September and got a few weeks of use out of the pool before it was time to have someone close it for us. We are getting ready to open the pool back up in a few weeks and I've been reading through this page getting ready to take care of the pool myself.
One project I need to complete before we open the pool is installing a new automatic pressure side cleaner. I guess a little summary of my current system would be helpful. The pool has two skimmers that feed through the pump an into a DE filter. A Hayward Vari-Flow valve controls the flow through the DE filter. The pump motor is a AOSmith model USQ 1102 (1HP, 115/230 V, 14.8/7.4 amp). Between the pump and the multiport valve is the dedicated pressure line that is controlled by a 3-way valve. The pressure line has a Jandy Energy Filter on it.
The discharge from the DE filter goes to a Raypak gas heater (model RP2100 or R185-R405?). After the heater is another 3 way valve that allows me to chose whether to send it to the returns or the pool drain. I think that is to turn the water over better and help with heating.
The cleaner was an old Ray Vac or something along those lines that didn't really do much at all other than spin in circles in the deep end. I was given a Polaris 280 and I need to install a booster pump to run it. I see that normally it would be installed after the filter and the heater, but it my case would it make sense to just install it after the Jandy Energy Filter rather than replumbing to put it after the heater? I understand that I need to make sure that the main pump is running when the booster is on, so I would need to put the booster on a switch rather than relying on a timer. Either way it isn't a big deal and will plumb it whatever way makes more sense.
My next issue is running power to the booster pump. The pool sub panel is fed by a 240 v 30 amp circuit from my main panel. The run is about 100 to 150 feet and they used 10 AWG wire. In the panel is a 20 A breaker that runs the pump (240V). The heater and a GFI outlet are also run off of that. The pool light is run off a separate breaker. I am not sure how much the gas heater draws and am wondering if I will have enough capacity to run a booster pump. I'm looking at the polaris pumps and it seems like they will draw about 7 amps at 240. I believe the main pump draws 7.4 at 240. There is room in the subpanel for additional breakers, but want to be sure that I'm not going to be taxing it. Thanks for any help.