The professionals I payed to install a rain water storage tank failed to install a suitable anti-backflow valve resulting in the water tank filling up with sewage (when the drain was blocked). I have now dug down and found the plastic pipes which require the value fitting, have found a supplier of a suitable valve and don't know what to do next.
Can anyone tell me...
1. How do I disconnect the existing plastic pipes? Do they just pull apart and if so how much pipe am I going to have to expose to be able to do so? Is there a technique to do this easily?
2. I believe that I need an access to the valve but looking at the inspection chambers available they all appear to be for junctions. Is there a special type of inspection chamber for an inline valve or some other solution?