Mistake 3: Running more than one feature off the same pump When you’re designing a smaller pool/spa combination for a cost-conscious homeowner, it might be appropriate to power the spa jets and pool filtration with the same pump.
A system becomes more effective, however, when you equip the pool, spa, and water features with their own pumps. It has even become standard practice to outfit a vanishing edge with its own pump. The homeowner has the option of switching on a spa, fountain, or vanishing edge without operating the filtration.
Mistake 4: No air break in a vanishing-edge system Without exaggeration, this mistake can prove disastrous. A vanishing edge is created when a higher pool spills into a lower vessel. It is then pumped back up to the main pool so it continues to overflow.
When the pump shuts off, the top pool stops overspilling. Anything that doesn’t fit into the main vessel settles into the lower basin.
At this point, gravity wants to take over. If it could, the water would escape the main pool through inlets, and flow backward through the plumbing to the catch basin below. Without check valves and an air break, it will do just that. But the smaller basin can’t hold the entire volume of the main pool, so it would overflow. In the worst of cases, these thousands of gallons of spillage can cause soil erosion on hillside properties for your clients or their neighbors.
To prevent this, builders need to introduce a barrier that will stop the water on its backward path. Check valves are a must, but they can fail. As a crucial backup, knowledgeable builders install a Hartford loop. This piece of plumbing comes up out of the ground until it’s higher than the main pool’s water level, then goes back down, forming an upside-down U. If water somehow escapes by going backwards, it won’t surmount the loop because of its elevation.
Keep in mind that the same precaution should be taken for spas or water-features that are tied to the main pool and sit at a lower elevation.
Mistake 5: Feeding jets or inlets off a straight line When sending water through a series of inlets or hydrotherapy jets, or designing a series of vertical plume fountains, the volume and pressure must be consistent from one to the next. This allows spa users to enjoy the same hydrotherapy pressure no matter where they are sitting, and will give the fountains the same height.
When building these outlets into a system, the builder should not simply run a trunk line then attach the smaller pipes for the jets, fountains, or outlets. As water moves through the trunk line and escapes little by little out of each subsequent fitting, pressure will drop. So the last jet will be weaker, or the final fountain shorter.
To avoid this problem, builders should feed the series through a plumbing manifold or loop. Water enters at the series’ midpoint, so it splits in two directions and only has to feed half the jets, fountains, or outlets. A manifold still runs in a straight line, with caps at the end. A plumbing loop is the ideal. Its ends are connected, so the water travels in a never-ending circle, guaranteeing consistent pressure.
