On 18/04/2019 22:02, Tim+ wrote:
AJH wrote:
My niece has asked me to "fix" her newish Dysaon DC54 which seems to be
suffering from too high a pressure drop across the canister which is
triggering some sort of shut off valve in the motor unit.

It was used to clean up some plaster, whether spilled fresh or sandings
I don't know.

I'll drag a cmpressed air line out and back flush each cyclone I can see
a spout for (42) but if that fails is there a chemical that will
dissolve plaster (calcium sulphate). I don't think brick acid will work
as it is weaker than sulphuric acid that would form the sulphate from chalk.

How soluble is set plaster?

AJH


Plaster will have blocked the filters. Unless youve accidentally sucked up
wet stuff, the cyclones are probably okay.

Yes. So much for Dyson's adverts of no filters and no loss of suction!

My experience of a couple of Dysons over the years (at a rental cottage
that we regularly use) has really put me off them. The filters clog
extremely easily (ash spilt when clearing out the stove) and (in the
case of the DC02) even the carboard disks and streamers from party
poppers jamming in the bend entering the body - whereas our Henry takes
plaster dust, ash or even the entire plastic bodies of part poppers in
its stride.

Wash/replace the filters.

Which is fine in this case, but if you are mid-way through vaccing, you
can't carry on until the filter has dried.

SteveW