PVC union help - Sand filter unit plumbing connections

[brunoforestier]

I'm completely new to dealing with plumbing in swimming pools, and have next to zero plumbing experience otherwise. That said, I'm still going to try and give this a go.

I need to visbily check the sand in my Tagelus TA-60 filter. I have never done anything with the filter, in the five years I've owned it, other than backwashing/rinsing it. The filter/pool was not new when I purchased the home, so it could be substantially longer since the filter sand has been replaced.

Attached are some photos of the plumbing and the multiport valve atop the unit.

Is the red glue-like material an indication I'll need to hacksaw the PVC?

Are there guides for people like me trying to work on a setup like mine? I tried searching and learned about PVC unions, and PVC glue. The PVC unions in my setup appear to have been glued/sealed?

 

[TO116]

I would try to unscrew the grey union at the heater. Then cut the other pipe and add a threaded union.

I just had to do this to my filter as well, similar situation.

It does look like someone cut and coupled the piping before to remove the MPV.