can this be used on a heating system?

You may be able to use the adaptor on a heating system with the correct washer/sealant, but check with a local plumber.

Will the female 22mm connector fit a G5/8 male connector?

A 5/8 BSP parallel internal thread will be about 20mm to 21mm across the flats and the fitting on Amazon is 22mm . your thread will be 14 TPI BSPP . BSP threads are very confusing as there were many changes over the years an NPT thread could as they are similar .

Manufacturer	Remer
Part Number	SU-AA-004
Package Dimensions	5.4 x 5.2 x 2.1 cm; 18.14 g
Item model number	SU-AA-004
Size	22 mm
Finish	Polished
Material	Metal
Item Package Quantity	1
Number of Pieces	1
Batteries included?	No
Batteries Required?	No
Item Weight	18.1 g

Remer Metal Adaptor Reduction for Water Faucet Tap 22mm Female to 1/2" BSP Male Joiner

Details

Description

Specifications

Common Questions