"Dave DesRoches" wrote:

My wife was vacuuming over the weekend and when she withdrew the hose from
the wall, the central vac continued to operate. The only way we could get
it to shut off was to physically unplug it at the main unit (where the bag
is). I checked the contacts at the wall plate - they seem ok - and I
emptied/replaced the bag. Any other ideas as to what the issue might be?

Thanks in advance for any thoughts you could share...

-Dave

I would guess you need to check for shorts in the low-voltage line.

Disconnect the low-voltage line from the vac unit
Does the unit still continue to run - if so you have an issue with the
vac unit (stuck solenoid)
Check the disconnected low-voltage line for a short - use a
multi-meter
if short discovered then it's a process of elimination on where it is
located - 1st check the dust-pan outlets (if you have any - sometimes
they don't close correctly and leave a short in the low voltage line)
Work around each of the other outlets - disconnecting the low voltage
line from each of them (a pain I know) and again check for shorts,
with the multi-meter
If they are all disconnected (outlets), and the short is still there -
it's on the line somewhere - look for damage if you can (rodent
maybe),

I had the opposite - I had an installer rough in the vac pipes and
cables, but he put a kink in the low-voltage line that gave an open
circuit - just as it entered the garage (so I discovered).

-Mike