I have been doing boiling water canning and recently decided to start
doing some pressure canning. I have a new Presto pressure canner and
got the gauge tested today. It is under by 1 lb. The person who tested
it at the cooperative extension said if I still follow the normal
pressure requirements I will be over by 1 lb. I emailed Presto to see
about getting a replacement since it is new and never been used. Has
anyone had this happen with a new gauge, is it common? I got the
canner on clearance at Walmart and there are no more so I can't return
it for another.

chele519 wrote:
> I have been doing boiling water canning and recently decided to start
> doing some pressure canning. I have a new Presto pressure canner and
> got the gauge tested today. It is under by 1 lb. The person who tested
> it at the cooperative extension said if I still follow the normal
> pressure requirements I will be over by 1 lb. I emailed Presto to see
> about getting a replacement since it is new and never been used. Has
> anyone had this happen with a new gauge, is it common? I got the
> canner on clearance at Walmart and there are no more so I can't return
> it for another.

Not unusual at all for a pressure gauge to be under or over by a small
percentage. Why swap it? The next one you get may be the same way. If it
is reading under by 1 lb then make a Sharpie mark at 10 lbs on the gauge
and that will give you the 11 lbs you're shooting for, you then know
it's under at higher pressures. My gauge is about 5 years old and I have
it tested annually and mark the proper pressure point on it.

George (who spent over 40 years working in chemical plants and used
sensitive gauges all that time)

1 pound over is ok too high a temperiture is much safer than too low.