I started getting my plumbing together for the return pump swap to the 2nd RD3 230. The plan is to do the swap on Sunday although I may do it Saturday afternoon as I am planning on help LA Fish Guy Jim with some plumbing at a customers on Saturday morning.
As I mentioned earlier, this pump swap will be a more a challenge compared to the first RD3 230 that I installed on my closed loop. The return pump plumbing was originally setup for a Hammerhead where as the closed loop was setup for a Dart. The way I had set my Darts up with the unions, the inlet union further away from the volute and the outlet union was higher up than the Hammerhead return pump. The RD3 with the fittings I needed to adapt it to my system works out perfect for replacing the Darts but is a pain when trying to adapt to the Hammerhead and in my case impossible on the exit side because of the hard plumbing.
As such, I was left with no choice but to change the exit side of the return plumbing. The inlet isn't an issue but on the exit side, it pushes the plumbing back about 1.5" and raises the union about 1.5". Not a huge deal as I was prepared to make this change and tend to be very organized and efficient when it comes to my plumbing. The good thing is that I will be able to keep just one pump for a spare which in this case will be a Super Dart Gold. It will be plug and play for either my return pump or the closed loop and have the unions on it so it can be swapped in with a moments notice should I have a pump failure. Once I get this swap done, that will give me a damn near new Hammerhead Gold and a Dart Gold to sell.
Below is a shot of my return plumbing. It's the plumbing on the right. I need to replace everything going out my existing return pump to just past the upper elbow that leads to the horizontal run. The blue valve leads to my chiller loop. The double union ball valve above that leads to my manifold and the line above that leads to my return in the tank. I will have to make one cut to remove the lines from the pump to the horizontal run above the elbow. I will install a union ball valve in the horizontal section and connect that to the new pump plumbing. The manifold line will be reconnected to a new double union ball valve so no cuts needed there and the chiller loop will likely need a new union ball valve as blue handle one is really old and I can't find another like it. Not a big deal though as I have other 1" union ball valves.
As I said, I really plan things out and in this case, I need to have everything laid out and as much preglued as possible so I can keep down time to a minimum. In this case, I would expect the system to be down no more than an hour. That will give me time to shut the return pump off, break the siphon at the top of the tank, close the valves before the return pump. Cut the line above the return. Remove the return, remove the old section of plumbing, glue the new union ball valve above the new section and finish up the new section. Really, I don't expect it to take more than 30 minutes total since I will only need to glue about 8 joints when all is said and done as I have already glue a bunch of it together. I could glue it all before hand but some of the fittings will need to be glued in place so things line up properly.
Here is a shot of the new RD3 230 return pump with the unions glued in place so they can be connected to the union ball valves on either side. You can also see the new T fitting glued to the double union ball valve that will leads to my manifold. The other T fitting will go to the chiller loop. This was taken with dim light so the colors are kind of funky..
This is how it will go together. Above the upper T will be an elbow leading to the union ball valve that will sit between this plumbing and the tank. If I ever need to mod the plumbing again, the extra union ball valve will make it easy and I won't need to cut things under there.