P
Plumb Duff
Hi all, I recently got with a pressurised water heater connections consisting of 3/4 brass nipples and brass couplings, the coupling has rubber seals and nylon internal thread, why would this be the case and can I not just directly couple to the water heater without the coupling supplied using 3/4 elbows to the water heater with the nipples fitted? What is the purpose of the supplied coupling? (attached photo)