Static shock from vacuuming log fire ash - why?

[readiescards]

Clever bods,

 

I'm most curious why every day when I clear out the log burner stove with my old but trusty DC04 Dyson vacuum cleaner I get one or two static electric shocks - resting my arm on the log burner top (learnt not to use my hand to rest as too sensitive).   Is ash flowing down a plastic tube an electrical generator?

 

Curious rather than concerned 

[Russell griffiths]

Be careful I know two different people who have set fire to their hoovers doing this. 

I just use a dustpan and brush and a metal bucket. 

Both swear it was stone cold. 

[readiescards]

3 minutes ago, Russell griffiths said:

Be careful I know two different people who have set fire to their hoovers doing this. 

I just use a dustpan and brush and a metal bucket. 

Both swear it was stone cold. 

 

Ooo, not thought of that, typically do it 12 hours after last log.  Not too worried if a 20 year old gets burned as long as it does not take my house with it!  Ta for warning

[Simplysimon]

10 minutes ago, readiescards said:

Clever bods,

 

I'm most curious why every day when I clear out the log burner stove

 

 

you must use a lot of timber, we clean ours about every three weeks.

[Russell griffiths]

I discovered ours after I had finished and the vacuum was sitting in the kitchen and started to smell a bit. 

Could have been nasty. 

[Onoff]

Its the friction of the ash going up the plastic hose. You can get anti static hoses but they "earth" to the machine. 

 

You could ground yourself to something via a wrist strap maybe. 

 

Get enough of a charge and it could ignite the dust even if "cold". Dust fires in things like flour mills are horrific. I worked at a mill where all the conduit systems were pressurised (to keep the dust out).

[readiescards]

4 minutes ago, Simplysimon said:

 

you must use a lot of timber, we clean ours about every three weeks.

 

Small 5 kW stove, with very small pan - used some days from 6am till 9pm = one and a bit small baskets of logs/day = ash pan brim full so easier to vacuum

[Simplysimon]

ours 5kw but only on in the evenings, aga little wenlock.

[Onoff]

Taken to the extreme you see flashes of lightning within volcanic eruptions and pyroclastic clouds.

[readiescards]

Ours is a ACR Oakdale with direct air feed

 

http://www.stovesonline.co.uk/wood_burning_stoves/ACR-Oakdale.html

 

Does seem to get through wood fast

[Simplysimon]

@readiescards does it put out much heat, i do appreciate 5kw! but running a low amount of wood as we are going passive but someone in the family wants another woodburner 

[readiescards]

It nicely heats a 5 by 15 m kitchen, dining, living room space in a brick and block house with 2.5 air tightness. After a 4 or 5 hours we start to really back it off as room temp gets to 23.5 degrees which is getting too warm really. 

 

In a full air tight house things might be different

[SteamyTea]

11 hours ago, Onoff said:

You could ground yourself to something via a wrist strap maybe. 

Or a stove.

 

I just see this as another danger of WBS, not one I have thought of, but I am sure I can 'sex it up' to make it really dangerous.  And add in a bit about EMF.

A picture of a hipster's beard going all spiky should do it.

 

Probably because of the type of plastic that Dyson uses, cheap Malaysian stuff.

[ProDave]

So let me understand this.

 

Instead of using the handle provided to withdraw the ash pan and tip it into a metal bucket (then hoover up any you drop) you leave he ash in the pan in the stove and suck it all out with the hoover.

 

WHY?

 

We leave the ash in the metal bucket for a very minimum of 24 hours before tipping it into the wheelie bin.

 

 

[readiescards]

I do hold the stove as a way of grounding me, but it still sparks across from my arm to the stove body - probably because the stove is enameled.

 

The Acr Oakdale has a very small ash pan so I can ether:

 

1. spend time forcing the ash from the fireplace into the ash pan, with-drawing the over full ash pan which dumps some ash into the base of the fire and then very carefully carry it through the house leaving a trail of dust (or tip it into a large bucket creating a dust cloud)

 

or

 

2. simply hoover the fireplace and then the ash pan

 

When the Dyson packs up I'll get a metal based vacuum cleaner something like:

https://www.espares.co.uk/product/es1674002

 

(The blowing feature looks handy - for helping me pull some chord through a long underground duct too)

 

 

[dpmiller]

metal based or not, it's the friction of the powder in the tube that causes problems.

 

/it's a long time since I sat my ATEX certification but I'll never underestimate the risks of moving dusts, just as @Onoff describes.

[readiescards]

Brought a little Wellco ash vacuum, seems to work fine and no electric shock :-)

 

Even got a useful blow feature that will help me fix a broken drawn cord in a duct without resorting to my car exhaust

[Temp]

+1 to what others have said.

 

It's a problem for grain stores. They make dust which is an explosion risk and create static electricity to detonate it.