My SWG is 7 years old, got error code 120 and after cleaning still getting code, so am replacing as this is likely culprit. Pulled the old PLC1400. Put in place the new item, aquapure that started with an R model # (was told by pool store this was identical to PLC1400) the unions on the replacement were smaller than the existing nuts, the same nuts that held in the old PLC1400. As I recall, the nuts provided in the box with the new SWG were too small for the old PLC1400. Am I making sense? Are these units made with different size unions or am I just an idiot. The pool store swore that the item they sold me was identical to the old PLC1400. Called Zodiac and they couldn't seem to figure out why I couldn't just drop in the new one and tighten existing nuts. Help?