DI Vessel Fittings - Removal and Alternatives

Looking for some help, because I'm beginning to feel moronic - this little blighter (pictured - GF Hozelock to 3/4" Male) is evading every tactic to remove it from our DI vessel. It came fitted by WCW, and we cannot find a square spanner to fit it, standard spanners (open and closed) spin around it, eating up the plastic, and pliers are destroying any chance of a proper tool to remove them. I'm at a loss! Any thoughts?

Also, were looking for recommendations for better fittings for DI Vessels. The ports are 3/4" BSP female. Ideally we want rid of hozelock fittings entirely! 

Thanks!

I would have thought it should come of very easily with the correct size spanner. if you are or were using plumbers pliers they will just slip on the plastic and damage the fitting, not sure if a damp cloth over the fitting then a spanner or plumbers pliers would work or these Strap Wrench Toolstaion

Yeah it should come out fairly easily. If it’s not then maybe it’s been cross threaded or just like fused in place after being there a long time. First thing I would try is... If you keep your DI’s outdoors try bringing the lid in overnight so it’s warm, then trying again or more likely vice versa. The temp change may help loosen it. 

I'd boil a kettle full of water and pour it over where the threads are.

Are you turning it the right way? Easy mistake to make.

I would use an adjustable spanner on that, should come out pretty easy unless it's been glued in.

Part Timer said:

I'd boil a kettle full of water and pour it over where the threads are.

Click to expand...

Heat could well do the trick, when it comes to changing my R/O membranes the plastic end cap is a nightmare to remove so I have to use a heat gun aka my wifes hairdryer then they unscrew very easily.