richardabeattie
Well-Known Member
Two sockets are clearly marked for inflation and deflation. But there's a third one in the middle. Baffled!
Middle socket on Avon foot pump.
- Thread starter richardabeattie
- Start date
Homer J
Well-Known Member
It is probably a high pressure outlet. Outlet 1 for speedy inflation outlet 2 for slow but high pressure (above 0.25 bar for e.g.)
prv
Well-Known Member
Exactly so. For use with air-decks, which have to be inflated to a higher pressure than tubes.
Pete
richardabeattie
Well-Known Member
How could two similar outlets in the same manual pump produce different pressures?
pvb
Well-Known Member
richardabeattie
Well-Known Member
OK - smoke and mirrors is a perfectly satisfactory explanation. So for pumping up a bog standard dinghy with a non inflatable floor I should ignore the central socket and use the one next to the hinges marked inflation.
paulajayne
Well-Known Member
Is it not the air in valve?
richardabeattie
Well-Known Member
No. The air goes in via some small holes near the central socket.
pvb
Well-Known Member
We don't know what sort of pump it is, but most with a third socket have that socket for higher pressure.
pyrojames
Well-Known Member
The central outlet is fed from a much smaller chamber, so the same force from your foot pushes a smaller volume and hence can give a higher pressure.
VicS
Well-Known Member
Yes
It is a two chamber pump. One chamber will deliver a large volume at a low pressure, the other, smaller, chamber will deliver a much smaller volume at a higher pressure.
It would take a lot of pumping to pump an entire dinghy up with the small chamber.
Its all just simple physics ... so it probably does not work!
Last edited:
richardabeattie
Well-Known Member
What does VicS not know?
pvb
Well-Known Member
VicS
Well-Known Member
Anything that's not on Google!
You shouldn't judge others by yourself.
