I installed three Magicstream Laminar Jets in 2016 when we built our pool, and they worked great for several years. But nowadays, instead of a nice perfect arc, we get "pulsing", primarily from the two closest to the supply. This has been going on for a few years now, and wondering what could be causing it? I've cleaned the cartridge filter in the supply for them, but not sure what else could be causing this. This is not only an aesthetic problem, but is also causing much more splashing and noise than when the smooth stream used to hit the pool surface with almost no splash. Any ideas? Below the picture is more info about the system in case that's helpful.
There are two drains on the side of the pool that go to the dedicated laminar pump via 2" pipe. It is a run of about 16', and the pump is located 6' below the pool deck. The pump is a Pentair Superflo 0.5HP. A 1.5" flex line runs 4' from the pump to the Pentair cartridge filter. Leaving the cartridge filter is a 1.5" flex line with a T and then it expands to 2" line into a check valve. From the other side of the T is a 3/4" line with a ball valve running back to the intake of the pump. From the check valve is 2" line running about 45' with a 7 foot height gain to the planter shown on the right in the picture. It has about five 90s and a couple 45s. The 2" line has two Ts and a reducer, so that three 1" PVC lines leave from it, each going to one of the three laminar jets. Just before each laminar jet is a ball valve to adjust flow to it.
Looking at the performance curve of the pump, I determined that the 1/2 hp pump would have about 20% more power than needed, so I wanted to error on the side of two much power (also, 1/2 HP was the smallest pump I could get from Pentair). Upon first test, all three jets hit the ceiling! By the time I turned their ball valves down enough to make the stream of reasonable height, the back pressure on the pump was very high and it was getting quite hot so that's why I installed the 3/4" return from the filter outlet back into the pump inlet. Even with this return to the inlet, the back pressure is still a tad bit on the high side, but no longer unreasonable.
Like I said at the beginning of the post, these worked great for many years. I'm confused as to what could have hapenned to cause this issue. I do not audibly hear the pump pulsing, it sounds very constant. Thanks for taking a look at this!
There are two drains on the side of the pool that go to the dedicated laminar pump via 2" pipe. It is a run of about 16', and the pump is located 6' below the pool deck. The pump is a Pentair Superflo 0.5HP. A 1.5" flex line runs 4' from the pump to the Pentair cartridge filter. Leaving the cartridge filter is a 1.5" flex line with a T and then it expands to 2" line into a check valve. From the other side of the T is a 3/4" line with a ball valve running back to the intake of the pump. From the check valve is 2" line running about 45' with a 7 foot height gain to the planter shown on the right in the picture. It has about five 90s and a couple 45s. The 2" line has two Ts and a reducer, so that three 1" PVC lines leave from it, each going to one of the three laminar jets. Just before each laminar jet is a ball valve to adjust flow to it.
Looking at the performance curve of the pump, I determined that the 1/2 hp pump would have about 20% more power than needed, so I wanted to error on the side of two much power (also, 1/2 HP was the smallest pump I could get from Pentair). Upon first test, all three jets hit the ceiling! By the time I turned their ball valves down enough to make the stream of reasonable height, the back pressure on the pump was very high and it was getting quite hot so that's why I installed the 3/4" return from the filter outlet back into the pump inlet. Even with this return to the inlet, the back pressure is still a tad bit on the high side, but no longer unreasonable.
Like I said at the beginning of the post, these worked great for many years. I'm confused as to what could have hapenned to cause this issue. I do not audibly hear the pump pulsing, it sounds very constant. Thanks for taking a look at this!
