My family experience with Grundfos pump at home:

I moved into a 3 storey house near 10 years ago, installed a Grundfos CH2-50 from my water tank outlet during renovation and been using it ever since. The water tank area and all the outlet pipes are in open air subject to sun and rain in my roof area, so the pipes all suffer some form of sun and rain. As the years go by, my dad and I have to cut and repair cracked pipes due to the high pressure and exposed pipes. We have so many rejoints now that we just replaced a full set of all the piping once early this year. Just to be clear, all our pipes are rated class 7.

Not to scare anyone away from using Grundfos pumps, but they are a powerful and highly durable workhorse. Just make sure you know where all your pipes run, cuz as your pipes age it may crack and some joints may also come loose due to vibration. Always pay attention to your pump making noise, if it makes noise too frequently even when no one has been using any water for some time, then u potentially have a pipe leak somewhere.

Previous pipe class 7, now also still class 7. Just that my water tank is on a cement platform on top of the roof, and it is exposed to sunlight and rain. Over time all the pipes in that area that is connected to the Grundfos pump cracks one way or another. Worst part is each time we rejoin, need to leave at least 12-24 hours for the joint to harden before turning on the pump again, else the joint will burst (just happened again yesterday).

I remember seeing before a commercial plastic pipe system that uses a special tool to heat melt the joints, but dunno where to get.