Festool CT 25 Particle counts - doesn't appear to be filtering

hello

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Hi Everyone,

I just bought a Festool CT 25 (my first festool) to replace an old Ridgid (Black Friday Special) with a Hepa filter. I have a dylos pro particle tester and wanted to see if having a full unit HEPA certification made a difference on the particles coming out of the unit.

The Ridgid did better. What am I missing? I'm going to reach out to festool support.

Brand New Festool CT 25 Extractor:
Held at exhaust with CT 25 suction setting on Low (Also tried high).
Particle Count goes Up > 800 (.5-micron particles)
1759270155988.png

Update: I placed the diffuser from the Ridgid into the CT 25 exhaust and the reading went way down.

1759339164680.png

Update 2:
The particle counts coming out of the air intake/exchange port on the left of the unit are > 10,000. This is expelling something. Could be motor particulates or oil particulates from the motor itself.

1759517119951.png
Ridgid Shop Vac with Aftermarket HEPA Filter (Non sealed unit):
Held at Ridgid Exhaust Port
Particle Count goes down (with and without shop vac exhaust diffuser).
< 5 (.5 micron particles)
1759270184521.png

Particle Tester: Dylos DC1100 Professional Air Quality Monitor
 
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Lots of things going on here. First is the fact that while I know a lot of woodworkers use that brand of sensors, it is very much not what I would consider a precision instrument by any means. The devices we use, for example, for clean room monitoring cost an order of magnitude more and still require regular calibration and verification. Even barring that, did you account for break-in of the filters, inducement of surrounding air, etc? Lots of unaccounted for variables could easily be giving erroneous results.
 
I do understand that the Dylos units are not professional units. However, I've found that they do offer a good representation of what's occurring. I don't have $3,000 plus dollars for a professional monitor.

I tested the CT 25 first then the Ridgid HD 1640 with the Ridgid VF8000 HEPA filter in a closed garage within 5 minutes of each other. The CT 25 test should have made the Ridgid test more challenging because any air streams stir up dust (as you know).

Additionally, I just ran my air filters in my closed garage until the particle count was near zero. I turned on the CT 25 and held the Dylos unit close to the exhaust and the particle count went up to over 1000 (this does not occur with the Ridgid). It looks like there is some sound proofing material down in the blower port. I'm wondering if that's what is blowing out.

There should be no break in of true HEPA filters. This is only for other dust collectors that do not have HEPA filters. These vacuums are rated for RRP work. It would be highly unethical for Festool to expect a break in period while a vacuum is spewing lead dust over a client's home.

If this is Festool's official response (it sounds like you might work for festool), I'll send this unit back.
 
I tested the CT 25 first then the Ridgid HD 1640 with the Ridgid VF8000 HEPA filter in a closed garage within 5 minutes of each other. The CT 25 test should have made the Ridgid test more challenging because any air streams stir up dust (as you know).

Additionally, I just ran my air filters in my closed garage until the particle count was near zero. I turned on the CT 25 and held the Dylos unit close to the exhaust and the particle count went up to over 1000 (this does not occur with the Ridgid). It looks like there is some sound proofing material down in the blower port. I'm wondering if that's what is blowing out.



If this is Festool's official response (it sounds like you might work for festool), I'll send this unit back.
I don't believe that is the official response from Festool. Festool responds on this forum using one of their accounts that indicate that they are Festool employees. Please note, although I may moderate this forum, I am not employed by Festool. Festool has not been active answering questions such as yours here for a long time. If you want help with your situation you should indeed contact Festool directly as you previously stated.

Peter
 
You held it where?

There is a secondary air flow to cool the motor. That just sucks in air from the environment and blows it out again, along with stuff that went into that path from previous use; unfiltered but slightly warmer.

Also; do both vacs contain the same type of dust?
 
You held it where?

There is a secondary air flow to cool the motor. That just sucks in air from the environment and blows it out again, along with stuff that went into that path from previous use; unfiltered but slightly warmer.

Also; do both vacs contain the same type of dust?

I placed the dylos intake into the exhaust from the blower port on the Festool. If you're looking at the front of the CT 25, it's on the right side. There is a little latch that opens so you can plug a hose into this port to function as a blower. Isn't this filtered air? I just updated my original post. I placed the diffuser from the Ridgid into the blower port of the Festool and took another reading. The .5 micron count went down to 4.

The Festool is empty and the Ridgid is full of wood dust (The Ridgid .5 micron count went down to 1).

From my research, the .3 micron dust seems to be the most dangerous dust. Maybe the Festool is capturing more .3-.499 micron dust (The dylos only measures dust as small as .5 micron).

I tested another Ridgid vac with the green HEPA like material and that was letting a lot more material blow by.

I really wish the Festool came with a diffuser.
 
I have a Dylos DC 1700 and I'll take it outdoors from time to time just to see how well it tracks the readings of the local air monitor that's about 1 mile away. I've tried it on 3 different occasions and each time it tracks the local air monitor well.
 
@hello - can you share a little more detail about the Ridgid green HEPA? That’s the version I used to upgrade my 14ga Ridgid.

The Ridgid Green HEPA was letting some particles go through the filter. The Ridgid description of that filter is "HEPA Like" which is misleading to consumers. I do not believe "HEPA Like" has to reach the same 99.97% of .3 microns that a true HEPA requires.

They released a new filter V8000 off the top of my head that has white filter material with orange end caps. This filter is a true Hepa filter. I also use cheap bags from amazon for the Ridgid.

The issue with the Ridgid vacuums is that they are not HEPA rated systems, so you can get some air that bypasses the filter. However, mine appeared to be doing well and I'm not sure what I've gained with the Festool Vacuum.

It is quieter. The fact that the exhaust is not diffused is really annoying to me. It raises the particles quite a bit by just stirring up dust on the floor (You get the same result walking around on carpet if you place the monitor there).

Basically, I can place my Ridgid in the center of the shop and turn it on. Because of the diffuser the particles don't go up. I can place this CT 25 right next to it and the particles will shoot up from 25 to around 450 just because it's stirring up dust. For reference, If I resaw an 8" board on my bandsaw in the shop the particles will go up to around 300.

Please remember I'm a dummy in a garage with a $250 particle tester (do your own research on health implications of this test).
 
I have a Dylos DC 1700 and I'll take it outdoors from time to time just to see how well it tracks the readings of the local air monitor that's about 1 mile away. I've tried it on 3 different occasions and each time it tracks the local air monitor well.
Good to know! I read a couple of blogs before purchasing and users were comparing the results to local air monitoring stations. There was always a pretty consistent correlation. The readings in my garage are always pretty consistent. It's pretty interesting how the particle count will skyrocket inside if someone blows out a candle or cooks without the stovetop vent on.
 
I think that outlet is supposed to be behind the filter yes. Not sure if it's still mixed with the motor cooling.

With diffuser you mean it spits out the air at lower velocity?

It's also important to note that one small leak around the filter will cause such readings.

I know from experience that if too much dust escapes at the tool you create it... the airflow created by the vac will make that go airborne real quick.
 
I think that outlet is supposed to be behind the filter yes. Not sure if it's still mixed with the motor cooling.

With diffuser you mean it spits out the air at lower velocity?

It's also important to note that one small leak around the filter will cause such readings.

I know from experience that if too much dust escapes at the tool you create it... the airflow created by the vac will make that go airborne real quick.

Yeah, it just makes the exhaust more spread out. I'm not sure why particles increased without the diffuser. Either it was funneling other air into the air stream or perhaps the stream of air going through the dylos was faster.

With the Festool being a certified HEPA system, air shouldn't be able to bypass the filter. I agree that things can go wrong though (that's why I like to test).

I'm not using this for Lead paint, but I wanted a vacuum that was sealed. Guess I read too much about dust you can't see :)

This is from the EPA:

According to the definition in 40 CFR 745.83:

"HEPA vacuum means a vacuum cleaner which has been designed with a high-efficiency particulate air (HEPA) filter as the last filtration stage. A HEPA filter is a filter that is capable of capturing particulates of 0.3 microns with 99.97% efficiency. The vacuum cleaner must be designed so that all the air drawn into the machine is expelled through the HEPA filter with none of the air leaking past it. HEPA vacuums must be operated and maintained in accordance with the manufacturer's instructions."

Therefore, renovation firms should look for a vacuum cleaner that was designed to be operated with a HEPA filter, rather than a shop vacuum that can be fitted with a HEPA filter in place of the original basic filter. A vacuum retrofitted with a HEPA filter is not necessarily properly sealed or designed so that all of the intake air goes through the HEPA filter. EPA also recommends that renovation firms ask the manufacturer or retailer whether the machine has been tested to ensure that it achieves the high efficiency required of a HEPA filter (capturing 99.97% of 0.3 micron particles).

Question Number: 23002-20634


Diffuser:
 
Home Depot has a shitty website just blocking all EU traffic.

Anyway; a slightly wrongly installed filter... for example; it was replaced but the new one sits on a rim of dust.. will negate the HEPA rating.
 
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