Phresh stealth hyper silent

I got this fan in 10" a couple of years ago, the fan speed adjuster didn't work out the box but I read online without this the fan runs full throttle, I didn't have any intention of running it at lower speed as it was so quiet anyway and wanted the best air exchange. As it was the first fan I bought I had nothing to compare the gust given out with. (edit) The fan was then put in a cupboard until this row

Fast forward to last week and the room was starting to get pretty warm and humid so as a quick fix I got a little 6 inch rvk which literally blew me away, cooled the room within 10 minutes. This got me wondering if the Phresh fan is shifting the air they claim, or if I have a faulty one. Phresh claim 1065 cfm the Rvk was second hand but guesstimate from online research is 400-500cfm. I cant see how the phresh can be shifting over twice as much air, it feels like a babies breath when I put my face against it.

All my ducting is as straight and short as possible on both fans.

What I can say is there was no smell from the room when I was running passively and when I put a cigarette paper at the crack of the bottom of the door it was sucked into the room, but I was only using 2 6 inch holes and an 8 inch hole into my chimney so I think the fan was working hard before I got the noisy as f rvk

So to cut a long question short, can anyone vouch that these big silent mix flow fans shift the air they claim, and does the way they shift it feel unimpressive? Or do I maybe have a faulty one/ overworked one from too little passive intakes?

Mixed flow fans suck ass IMO, they don't deal with static pressure loss well so ducting really reduces flow.. To really move air you want a centrifugal blower.

Renfro said:

Mixed flow fans suck ass IMO, they don't deal with static pressure loss well so ducting really reduces flow.. To really move air you want a centrifugal blower.

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Yeah I'm not sure how bad the filter affects it too, I did go for a 12" though. Heats under control and the room I extract to is noticeably warmer. There's no smell from the room yet in week 5, so I'm hoping there's still some decent negative pressure.

Those blowers look great but the quietest one I saw was about 50db. I live in a small apartment in a built up area, I find it difficult to sleep with the 6 inch rvk as it is.

Hoping I'm at least getting enough airflow for maximum co2 for my setup. 4x8 grow space in 10x10x10 room with 3x660 watts HPS. Doubt I'm getting near 1065cfm claimed by phresh, but including the penalty for amount of lights and filter I only need a little more than half that.

The drop off with any resistance can be huge with some fans and not so much with others. Like renfro said, mixed flow are bad for this.

But also a 6" fan pushing air at 500cfm will feel to your face far more powerful than a 10" fan pushing 1000cfm at your face.

A 6" fan orifice is 28.27 square inch.
A 10" fan orifice is 78.54 square inch.

So pushing 500cfm through a 28.27 square inch hole air will be moving faster than 1000cfm through a 78.54 inch square hole.

coreywebster said:

The drop off with any resistance can be huge with some fans and not so much with others. Like renfro said, mixed flow are bad for this.

But also a 6" fan pushing air at 500cfm will feel to your face far more powerful than a 10" fan pushing 1000cfm at your face.

A 6" fan orifice is 28.27 square inch.
A 10" fan orifice is 78.54 square inch.

So pushing 500cfm through a 28.27 square inch hole air will be moving faster than 1000cfm through a 78.54 inch square hole.

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Hey thanks! Thats what I needed to know, im thinking of getting another mix flow for the intake as I'm not into the constant noise, even a big bowl of couch lock wont wont send me off, so that puts my mind at rest. Even at 4am i would really have to listen out for the Phresh, so maybe another 10 or an 8 with a speed controller

They do make duct mufflers that can help with the noise of the fans. They work best in duct runs, not just put it on the fan and call it done.

If you wanna see how much are you are actually moving, grab a cheap anemometer, then put it where the air is flowing and measure the velocity in feet per minute, or convert the supplied figure to feet per minute. Calculate the area of the orifice your air is moving through, that is your Duct Cross Sectional Area, a square hole it's just length x width, for a circle it's 3.14 x the radius squared. Multiply the velocity in feet per second by the DCSA (in square feet), you may need to convert your numbers, google is handy for this. Now you have a real world CFM number.

I have the 6" model of the hyper/phresh silent fan, it's got absurd static pressure n moves tons of air, spanks my old'ish canfans. Imo get your speed controller functional cuzz something's wrong if it's not acting like a black hole device.

Maybe the built-in fan speed adjuster on the 10" is stuck in low gear. What type is it?

Renfro said:

If you wanna see how much are you are actually moving, grab a cheap anemometer, then put it where the air is flowing and measure the velocity in feet per minute, or convert the supplied figure to feet per minute. Calculate the area of the orifice your air is moving through, that is your Duct Cross Sectional Area, a square hole it's just length x width, for a circle it's 3.14 x the radius squared. Multiply the velocity in feet per second by the DCSA (in square feet), you may need to convert your numbers, google is handy for this. Now you have a real world CFM number.

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I actually have http://www.reedinstruments.com/product/reed-lm-8000-multi-function-windmeter

I thought there would somehow be a way to use it to measure it but wasn't sure how to ask google, going to try get a nights sleep and get on it tomorrow, really I'll lie thinking about it and end up up a set of ladders at 4am. nice one cheers

Bubblin said:

I have the 6" model of the hyper/phresh silent fan, it's got absurd static pressure n moves tons of air, spanks my old'ish canfans. Imo get your speed controller functional cuzz something's wrong if it's not acting like a black hole device.

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Yeah it really does feel unimpressive when you put your face up to it,but going to put renfros calculations to task and put the ambiguity to bed! Will report back with results

OldMedUser said:

Maybe the built-in fan speed adjuster on the 10" is stuck in low gear. What type is it?

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I've dug out the adjuster and going to fiddle with it tomorrow, can be a bit lackadaisical, if its not working in 5 mins and didn't think I needed it I'd have lost interest pretty quick lol(edit) Its this one
https://www.futuregarden.co.uk/phresh-hyper-fans-stealth

Renfro said:

They do make duct mufflers that can help with the noise of the fans. They work best in duct runs, not just put it on the fan and call it done.

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I have a 10 inch muffler I got for the silent fan in case it wasn't quiet and never got round to sending it back, hm wonder if I could et a 10>6 inch reducer haha

McFrosticles said:

I have a 10 inch muffler I got for the silent fan in case it wasn't quiet and never got round to sending it back, hm wonder if I could et a 10>6 inch reducer haha

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You might have to get a 10-8" and 8-6" to make it work tho any big HVAC store could probably make you one up pretty quick for not a lot of money.

If that speed controller is a separate unit then the fan must be running full bore so unless it's screwed up then that's what you got.

I made my own speed controller out of ceiling fan controller I put in an electrical box with cords out each end. Then plugged it into my watt meter and marked where the fan was at half speed going by watts used as the dial was turned down. 120 at max so 60 at half. 6" n0-name POS inline fan about due for replacement.

I want one of these in it's 8" version. Vortex 'S' series. Sexay!

OldMedUser said:

You might have to get a 10-8" and 8-6" to make it work tho any big HVAC store could probably make you one up pretty quick for not a lot of money.

If that speed controller is a separate unit then the fan must be running full bore so unless it's screwed up then that's what you got.

I made my own speed controller out of ceiling fan controller I put in an electrical box with cords out each end. Then plugged it into my watt meter and marked where the fan was at half speed going by watts used as the dial was turned down. 120 at max so 60 at half. 6" n0-name POS inline fan about due for replacement.

I want one of these in it's 8" version. Vortex 'S' series. Sexay!

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Yeah it is a little separate cheap looking digital dial thing, looks like it came out a cereal box. That's why I chucked it at the time as I had no intention reducing it.

That's the sort of stuff that get's me electrocuted! I grabbed the end of a live lead I was soldering to lengthen it a couple of weeks ago, plugged the kettle plug in instead of the solder iron. After that I'm being as hands off as I can haha

That fan looks a piece of art! I'm looking at the soler and palau ones atm. They're all so bloody expensive though

That Vortex is sweet all right. Around $240Can and made in Canada. No speed controller on it but comes with a 10 year warranty and all sorts of good features. Doesn't move as much air as other 8" units but I don't need massive air movement so not a concern. No worries about noise either tho that one has built in sound deadening features as well. Could get a couple of cheap ones for that price but not so nice.

I'm careful about wiring and bought a code book to make sure I hook thing up right. I've run wiring from the main panel to make extra outlets in the grow room and out to the carport for outside plugs and a dusk to dawn light in front of the carport. No problems after 15 years. I'm no electrician but that stuff ain't rocket science. lol

The fan controller is on the left plugged into the Temp/RH controller.



I bought a 500W baseboard heater for the room and it wasn't until I wired it up that I realized it was 240V and barely got warm with only 120. Next project is to run 240 in there and wire it all up with a thermostat. ATM I'm just running a box heater using a baseboard heater thermostat wired up like the speed controller one. Works but more clutter in the room.

That was a huge help @Renfro , found a handy little calculator to save me making any mistakes. The fan is providing the cfm advertised while sucking through a filter and a 180 degree bend so more than happy. I input the m/s as 2.4 but it was fliping between 2.4 and 2.5, so actually a little better than the values given.

Mind at ease, cheers!

https://www.engineering.com/calculators/airflow.htm

Link to the calculator if anyone is interested

OldMedUser said:

That Vortex is sweet all right. Around $240Can and made in Canada. No speed controller on it but comes with a 10 year warranty and all sorts of good features. Doesn't move as much air as other 8" units but I don't need massive air movement so not a concern. No worries about noise either tho that one has built in sound deadening features as well. Could get a couple of cheap ones for that price but not so nice.

I'm careful about wiring and bought a code book to make sure I hook thing up right. I've run wiring from the main panel to make extra outlets in the grow room and out to the carport for outside plugs and a dusk to dawn light in front of the carport. No problems after 15 years. I'm no electrician but that stuff ain't rocket science. lol

The fan controller is on the left plugged into the Temp/RH controller.

View attachment 4344220

I bought a 500W baseboard heater for the room and it wasn't until I wired it up that I realized it was 240V and barely got warm with only 120. Next project is to run 240 in there and wire it all up with a thermostat. ATM I'm just running a box heater using a baseboard heater thermostat wired up like the speed controller one. Works but more clutter in the room.

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"Sound deadening features" need some of that in my life

Not rocket science but certainly some hands on stuff I wouldn't want to be meddling in. Obviously like to get your hands dirty!

McFrosticles said:

"Sound deadening features" need some of that in my life

Not rocket science but certainly some hands on stuff I wouldn't want to be meddling in. Obviously like to get your hands dirty!

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You could say that. Jack of all trades. Master of none. Do have a diploma in environmental chemistry tho after going back to school in my 30's for 3 years. Almost 30 years since I graduated that and ended up driving truck for a living up to about 5 years ago when health issues forced me to retire early. Will become an official old fart in Oct when I start collecting old age security.

Nice link for the air flow calculator. When I was at tech school they had a smoking room in the Sci/tech wing where I hung out that they were thinking of closing as it was fairly small and often crowded. One of my professors liked to stop in for a smoke and got me to measure the air exchange in there. Turned out it could support up to 50 people all smoking at the same time and it was never that bad so the room was saved and I got extra credit for the great job I did on the report.

I've had this calculation for how much air exchange is needed based on using HID lights for ages. Never really used it tho and don't think it's complete enough to be much help. No input for incoming air temp and how it would influence room temp. Down in my basement it can get as cold as 35F and as warm as 64F depending on season and all the air going into the grow room comes from the larger area down there.