# Dewalt DWV902M type 2 Dust Extractor Alarm keeps Sounding



## Housewife

Hi

I'm new to the forum so hello to everyone. I live in Italy but am English speaking.

I was so excited to get my Dust Extractor and thought I was finally on my way to better air and clean workspace. I bought this as I have 19 window shutters to sand down and didn't want to be breathing all that fine dust.

Started work, but the alarm keeps sounding off, ( poor neighbours) which according to the manual means the flow rate has dropped below 20 m/s. I have a Orbital Bosch Pex 300 270 watt, and a Orbital Skil 6-in-1 sander 270 watt. Both send the DE into a tizzy!

This is what I've checked:

Running the machine without any hose....Fine.

Running the machine with hose, but not connected to any electric tool...Fine.

When I connect it to the sanders the alarm starts after a few seconds and won't stop. The setting for the tube is 32mm. I've played around with the airflow and pipe diameter setting... nothing helps. I've even tried just holding the sanders in the air away from the work piece, same problem.

I am using all Dewalt connectors and the tube that came with the Dewalt system.
The connections are good with no air escaping, airlock in the lock position.. Tomorrow I'll tape the connectors and try again just in case.

I am using a shorter hose ( same diameter but from an old vacuum cleaner) for a table saw and there is no alarm sound.
I tried using the shorter tube for the orbital sanders, but the alarm goes off again.

As far as I can tell there is no blockage in the tube and no holes or cuts along the hose.. that I can see or feel. I have shaken it and used a compressor at 8 Bar to blow air through it. Tomorrow I'll run it and knock the hose along it's length. 

The filter bag only has about 1 cm of dust in it at the bottom. There is a tiny bit of very fine sawdust in the bottom of the bucket.

There is nothing blocking the filters or inside the filters of the machine and they are still pristine. They self clean every 15 sec, I'm also working outside, so nothing blocking the air vents of the machine.

Anyone have any ideas? Are the holes too small on the sanding pad and are mucking about with the airflow? 

I really am at a loss. Now I feel like "what the hell" after forking out all that money.
I've emaled Dewalt Services and the shop that sold it to me. No replies yet.


----------



## Steve Neul

My guess is not enough air can pass through the tools to suite the vacuum. You may have to create a leak to shut it up.


----------



## woodnthings

*your location is ...?*

This is your DE? http://www.buymetools.co.uk/dewalt/DeWalt-80065.html









Sounds like it's UK model?
Anyway, a simple test is to run the DE with just the standard supplied hose. Then place your hand over the end to restrict the flow. Does it sound the alarm when partially or fully restricted? If not, attach the sander without a sanding disc. Does it sound the alarm now? If not place the sanding disac on the sander and see what happens. Come back with your results!


----------



## Housewife

That was a quick reply!

Yes I did do that as well yesterday. Blocking the end of the pipe sounds off the alarm. Attaching the sander without a sanding disc is fine... Elimination by mistake that one, thought I'd solved the problem only to realise I had no sanding disc on it. Haha. 

Sooooo basically the holes on the sanding disc are too small and restricts the air flow?!!!!. My skil has elongated holes on the disc, I'll try enlarging the holes on the sanding disc and see if that works.

@ Steve Neul. How would I create a leak?


----------



## Steve Neul

Housewife said:


> That was a quick reply!
> 
> Yes I did do that as well yesterday. Blocking the end of the pipe sounds off the alarm. Attaching the sander without a sanding disc is fine... Elimination by mistake that one, thought I'd solved the problem only to realise I had no sanding disc on it. Haha.
> 
> Sooooo basically the holes on the sanding disc are too small and restricts the air flow?!!!!. My skil has elongated holes on the disc, I'll try enlarging the holes on the sanding disc and see if that works.
> 
> @ Steve Neul. How would I create a leak?


You could create a leak with a Y connector. Hook your hose onto one side of the Y and either leave the other side open or partially obstruct it with tape. Then the vacuum could draw more air. If you had more than one sander with another length of hose you could also attach the vacuum to both sanders which would create more airflow.


----------



## epicfail48

Im with steve on this one, the sander is restricting airflow. The same thing happens with my shopvac, though fortunately it doesnt have an annoying alarm, just a light. Finding a way to instoduce a leak to keep up airflow is certainly one option, and probably the quickest to do. Personally, id find an abrasive that would allow more airflow. Here in the states we have a product called abranet, its a mesh abrasive that actually allows air to flow through the full face of the disc. May be worth looking into, if you can find it. It costs a little more than regular sandpaper, but it lasts forever. I use it to sand my knife handles, and its really fantastic stuff. Doesnt clog, comes in handy for the exotics


----------



## Housewife

Thank you for the great and easy solutions to solve this very annoying problem. I was thinking about trading down :-(, until you mentioned the same problem with a shop vac. Mirka sell am abrasive disc called Abralon which allows water and air to pass, maybe a similar product. Just so happens I'm going to that store today!

In retrospect I didn't have the alarm problem so much on the first day... now I remember I was using the corner triangle base plate which has 11 holes, the round base plates only having 8! 

Wow, I feel so much better. I'd hate to admit I made a mistake buying the Dewalt, especially to the hubby who want me to go with something much cheaper.

You all have a great day.


----------



## yvilas

Hi. I'm having same problem with the dwv902m. Tried looking for the causes of continious alarms. noticed, that when the extractor has no hose attached, it works fine. But when the hose (any size) is attached, the alarm starts in a few seconds. Some guys here mentioned "Y" connector. There's no such original part with this model, trying to adopt something to work sounds a bit wrong (because machine is not designed/created to work with self-made/adopted connectors). I'm using various power tools (mitre saw, plunge saw, planner, router) plugged into extractor, the machine is almost brand new, though this alarm problem started after few days of usage. First, I have ignored it, though tried looking for solutions online, but when started working in close quarters (smaller rooms), the sound is too loud to be ignored anymore.

Would appreciate on any advise.


----------



## Bellarosecabinets

It is a faulty vacuum and cheap design that uses a resistor for determining air flow by cooling the resistor. To save money that went with a cheap solution that wood dust just doesn't work well with.


----------



## Housewife

I took mine to a Dewalt service center and got them to remove the alarm. The Y connector worked, but I didn't like the extra hose lying on the floor. Mine is used for a home workshop and not commercially. Also clean the filters on a regular bases, tapping them against something and NOT with an air compressor. It doesn't warrant the price. Shame on you De Walt.


----------

