Can this drain valve be replaced with an isolation valve?

[Tog-]

I am renovating my bathroom and have struggled to get a plumber on site.
I have decided to attempt some of the pipework myself as I can't continue with anything until some of it is done.

When removing the old bath I found the hot water feed to the taps has what appears to be a drain valve on it. Can I remove this and replace it with an isolation valve instead?

The central heating/hot water has been changed to a combi boiler, I don't know if that makes a difference?

 

[Notch7]

Is the hose outlet the other side then?

It looks more like a check valve, did the bath have a mixer tap on it

 

[Tog-]

There isn't a hose outlet on it at all, so clearly not a drain valve, thank you for pointing that out.

It did have a mixer tap on it yes. Had hot and cold feed going to it.

Same question I guess though, can it be swapped for an isolation valve or is important to the plumbing system?

 

[Madrab]

I'd say that's more likely to an old lockshield ISO valve, if so then yes it could be changed after isolating all the water. Use a good quality ISO valve. While you're at it put one on the cold supply too, good for servicing if any when required.

 

[Tog-]

It has a square "key" slot like when you bleed a radiator, when I tried to turn it, naively thinking it was an isolation valve water started coming out, hence why I assumed it was a drain valve.