Thanks Tony ! That makes sense ! I only take a spare pair when I've got the runs. Pumps in my family never fail except on Christmas Eves. I had a boiler crack one Christmas Day and we lived with towels on the floor and a hissing sound with every drip for two weeks.
Brian
Since having a pump fail late one Christmas Eve I have always kept a spare. At present I have a Grundfos selectric 15-60 which is almost new. However, instead of 1.5" flanges which fit tightly against isolating valves, this pump has 1" male connections at either side. These need to be enlarged...