Electric indoor brewers: What size (CFM) bathroom fan? (pics)

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kal

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Question for you electric indoor brewers: What size (CFM) range hood or bathroom ceiling fan do you use?

My electric setup is in a basement coldroom that is very small: 5.6' wide, 11' long, 7' high. 60 sq feet of floor space, 430 cubic feet of air. There are two 4" diameter vents to the outside of the house. One will be used for air intake, the other will be attached to a bathroom ceiling fan directly above the boil kettle to exhaust to outside. It's only a 4 foot distance without bends so any CFM drop due to resistance should be minimal.

100 CFM enough? 200 CFM? More? Without actually doing a 10-15 gallon full wort boil for an hour or two, I have no idea what I'll need. The room has a solid core door between it and the rest of the house.

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Kal
 
Yup. Pictures were taken with an extreme wide angle lens (Canon 10-22mm EFS).

Kal
 
The tiled ceiling will sure help with moisture control, but I'd recommend you get an inexpensive kitchen hood with a fan and maybe even put a pull-fan at the outlet. Being electric you don't have to worry about CO2 or CO but I would try to remove as much moisture from your basement as possible so you don't end up with mold problems.

Very nice setup BTW.
 
If it were me I would be looking at commercial sized vent hood fan, assuming the noise did not drive you nutty. Thinking its like taking a two hour hot shower and after, you realize that the typical bathroom vent fan just did not do the job. I would go with 400 CFM on a variable control (rheostat) switch, which is what I used when I had a commercial style kitchen hood in my old house. I'd also wear earbuds plugged into a walkman or ipod.

Also hopefully you have fresh air coming in and have not sealed up the door too tight. Nice looking brew room - do you have a floor drain so you hose the place down when
done brewing?

I really want that sink & commercial style faucet - any pricing/model info you can pass along- must have now! LOL
 
The inline fan from vortex I just put in works great and its wisper quiet. With that smaller space I would use the 4" model. You can always put a cheap speed controller on it and dial it down. Better to have more fan then not enough.

Mike
 
Nice setup! I would think a 100 cfm fan would be enough as it would provide an exchange of air every 5 minutes or so. However, this depends on where your air inlet is located. Is it located in the same hole as the outlet? If the inlet is too close to the outlet, you could "short circuit" your air flow and moisture could build up in the other areas of your brew room. Another consideration is that the outlet pipe will have very moist air flowing through it. You should slope the outlet pipe away from your fan. In other words, it is likely that water will condense in the outlet pipe, collect, and then flow. You don't want it to trickle back into the room and drip into your boil kettle when you turn off the fan.
 
Thanks guys!

Also hopefully you have fresh air coming in and have not sealed up the door too tight.

Nice setup! I would think a 100 cfm fan would be enough as it would provide an exchange of air every 5 minutes or so. However, this depends on where your air inlet is located. Is it located in the same hole as the outlet? If the inlet is too close to the outlet, you could "short circuit" your air flow and moisture could build up in the other areas of your brew room.
I've added a couple of photos to my original post to help see the big picture and answer your questions. Let me know what you think:

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Nice looking brew room - do you have a floor drain so you hose the place down when done brewing?
I installed have a drain (stack) for the sink but no floor drain unfortunately. It's something I would have really liked (so that I could simply hose things down and be done with) but that would require digging up part of the concrete floor to put in a trap and then retiling. Not worth it IMHO.

I really want that sink & commercial style faucet - any pricing/model info you can pass along- must have now! LOL
The sink was bought locally (Canadian made) from a restaurant supply store. Brand name is Tarrison, model PS1-24. Here's a PDF: http://www.tarrison.com/catalog/catalog_sections/Tarrison_pg.16-21.pdf

Figure $300-400 USD for a single tube stainless sink, no faucet(s). Ebay has nice sinks too but being in Canada means that the shipping would have been insane so I bought the sink locally. Shipping within the US is typically very cheap for anything.

The pre-rinse unit with 12" facet is from B&K Resources out of the US. MOdel # BKF-VSMPR-WB-AF12. Link: https://bk-resources.c2.ixwebhosting.com/Groups.asp?Prod=3&Page=1&Group=0&hdg=Prerinse Units
Bought off of ebay for ~$130. About 1/3 the price of buying locally even after you add in any extra taxes/fees/duties.

Kal
 
I have a 160CFM range hood. I'd double that if I was to do it over again. On a 60 minute boil I get condensation on the hood itself, some steam also escapes around the outside.
 
Another consideration is that the outlet pipe will have very moist air flowing through it. You should slope the outlet pipe away from your fan. In other words, it is likely that water will condense in the outlet pipe, collect, and then flow. You don't want it to trickle back into the room and drip into your boil kettle when you turn off the fan.
Good point. Putting a slope in will (unfortunately) not be possible as the outlet outside the house is actually a couple of inches higher. I was hoping (maybe naively) to be able to keep running the fan for a good 20-30 mins after the boil to make sure all humidity was out. This would (hopefully?) dry out most of the water too (?).

Kal
 
4" vents are pretty constrictive. I would make them 6" or 8" for better flow and less noise, if possible. Especially if you put in a 400 cfm vent. A nice large stainless hood sure would look and work good in that room with those blingmanns...
 
I have a 160CFM range hood. I'd double that if I was to do it over again. On a 60 minute boil I get condensation on the hood itself, some steam also escapes around the outside.
Thanks!

Is the range hood directly connected to the outside like a 'typical' install over a stove? Or is there a distance to go with lots of twists and turns? What diameter duct? Just curious as these all factor into greatly reducing the overall CFM. That 160CFM fan may only be doing 80CFM once you factor in the duct distance/diameter/turns.

Kal
 
4" vents are pretty constrictive. I would make them 6" or 8" for better flow and less noise, if possible. Especially if you put in a 400 cfm vent.
You've read my mind...

I'm starting to think that a 4" diameter duct isn't going to be enough. Range hoods typically use a 7" circular duct or a 10x3" rectangular duct. That gives you a LOT more air movement and less air flow restriction. In fact, the larger bathroom ceiling fans also use larger 10x3" rectangular ducts to get the 200+ CFM that some of them are capable of doing.

Those holes to the outside are 4" in diameter and go through almost a foot of concrete as they're in the house poured foundation (this is a basement room)! I have no idea how I'd enlarge those or if I'd even want to attempt something like that. Crap.

Kal
 
"Those holes to the outside are 4" in diameter and go through almost a foot of concrete as they're in the house poured foundation (this is a basement room)! I have no idea how I'd enlarge those or if I'd even want to attempt something like that. Crap."

I bet a convict could do it with a tooth brush...LoL

There must be some tool for the job. Not sure what I would do for that one. Hmmm.
 
After looking at the pics again, it looks like those holes were made after the room? Like they were chiseled or sawzall'd.
 
I would trade a handy friend some brew or something. I don't think it's impossible to make at least the outtake bigger.
 
The inline fan from vortex I just put in works great and its wisper quiet. With that smaller space I would use the 4" model. You can always put a cheap speed controller on it and dial it down. Better to have more fan then not enough.
Interesting Mike. Is it rated for use in humid locations? Other inline fans (like Nutone) are not for use in bathrooms. Got a link to the Vortex manufacturer website by chance? Google's only finding hydroponic sites that resell it.

Edit: Vortex fans are build by a company called 'Atmosphere' out of Canada. Found their website here: http://www.atmosphere.com/English/vortex.htm
No info on humidity but given that they're used mostly by dope growers in high humdity environments and run 24/7, I'd probably be ok. :)

Kal
 
Running the fan for a while after the brew should take care of the condensation. You could also install a "lowpoint" in the duct between the fan and the wall. It could be a "tee" with the bottom pointing towards your sink. Put a valve on the tee or even a threaded plug and open it up after you're done brewing.

The location of the air intake might be a problem. It looks the incoming air would "channel" directly from the intake to the fan. You could consider putting an elbow on the intake and directing it towards the floor. Another idea would be to install two fans and exhaust out both holes and leave the door open for the air intake.

By the way - that triple Blichman setup looks really nice.
 
After looking at the pics again, it looks like those holes were made after the room? Like they were chiseled or sawzall'd.
The holes are building installed (all the houses on the street have them). The previous owner for whatever reason framed and drywalled this cold room, and then decided to go with tiled walls on top of that. So everything's dropped a bit and in a bit so the vents are slightly offset.

Kal
 
Running the fan for a while after the brew should take care of the condensation. You could also install a "lowpoint" in the duct between the fan and the wall. It could be a "tee" with the bottom pointing towards your sink. Put a valve on the tee or even a threaded plug and open it up after you're done brewing.
Not a bad idea. The duct passes directly over the sink (which I always thought would be a pain).

The location of the air intake might be a problem. It looks the incoming air would "channel" directly from the intake to the fan. You could consider putting an elbow on the intake and directing it towards the floor. Another idea would be to install two fans and exhaust out both holes and leave the door open for the air intake.
Yes, some sort of 4" pipe to the floor or at least half way into the room along the wall would help. Exhausting out both is also an interesting idea. That would double the output without me having to chisel or try and make one existing hole bigger.

By the way - that triple Blichman setup looks really nice.
Thanks! I like it too. ;)

Kal
 
I would maybe get 2 inline 4" fans and exhaust out both of those ports and either leave the door open or install a square vent in the bottom half of the door so it could stay shut if that was needed.
 
Thanks. That's a pretty direct path and 7" is a huge duct:


I'm going to have to do bigger/larger for sure than what I thought of doing (which was around 200CFM into a 4" duct).

Kal


It does cut down the moisture a lot, but better to run it right the first time now that you know. As suggested by the other poster I'd do the two 4" ducts with inline fans (Or squirrel cages at the ends?). If it is worth doing... it is worth over-doing :)
 
I would maybe get 2 inline 4" fans and exhaust out both of those ports and either leave the door open or install a square vent in the bottom half of the door so it could stay shut if that was needed.

That is what I was thinking, use both those holes as exhaust, and get your make up air from the rest of the house, or at least from another room, so you do not end up with the channeling issue someone else mentioned. But then you are blowing a lot of heat out of the house in the winter. Perhaps you have another air source in your basement?

I love that room. Being in the south, my first thought was, Man it is going to get HOT in that room, but that is probably not your real concern:).
 
Thanks guys - been thinking about this more and the dual 4" in-line exhaust seems to make the most sense in my head too.

Just not sure what to put over the kettle to funnel. Some sort of hood?

Kal
 
One thing you could do to enlarge the holes. Lay out the bigger holes with a piece of cardboard. Once you go over it in your mind about 10 times, rent/borrow a 1/2" hammer drill and 1/4" & 3/8" bits. You should be able to rent/buy long enough drill bits to get through. Even if it won't quite go all the way through, you can make it work with 2 passes. Then, drill around the perimeter of the circle with the small bit making the holes 1/2" apart. Go back around with the big bit and enlarge the perimeter holes. Take a chisel and 4lb. shop hammer and connect the dots. Remember, you are going to slick down the outside with mortar or something stronger so even if the hole is ugly, you can fix it. That's such a nice room that it would be a shame not to have it as "perfect" as possible. Luck - Dwain
 
I don't use a hood at all. All electric, 5 gallon batches. 800 square foot finished basement - all very open. Just run a fan to disperse the steam and always have a dehumidifier. Been doing this for over a year. Never have condensation on anything or "clouds of steam." Maybe because I have a relatively large space? FWIW, before I finished it, it was 80-90% humidity in the basement - that's just part of living in Georgia. I keep it at 40% now.
 
One thing you could do to enlarge the holes. Lay out the bigger holes with a piece of cardboard. Once you go over it in your mind about 10 times, rent/borrow a 1/2" hammer drill and 1/4" & 3/8" bits. You should be able to rent/buy long enough drill bits to get through. Even if it won't quite go all the way through, you can make it work with 2 passes. Then, drill around the perimeter of the circle with the small bit making the holes 1/2" apart. Go back around with the big bit and enlarge the perimeter holes. Take a chisel and 4lb. shop hammer and connect the dots. Remember, you are going to slick down the outside with mortar or something stronger so even if the hole is ugly, you can fix it. That's such a nice room that it would be a shame not to have it as "perfect" as possible. Luck - Dwain
Good idea Dwain. I actually have a hammer drill (not sure if it's 1/2" - probably not) and bits of all sizes with a 12" extension rod. I'll try with the holes that are there now and if there's too much CFM drop I'll go with making one of the holes bigger (to 6" probably).

I've been thinking about the condensate hood. I have no need for anything too huge (I don't think). I'm thinking about having a shop make up stainless box something like this commercial unit:

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Commercial stainless condensate hoods are crazy expensive ($700 to the sky's the limit) and most are too big anyway.

I'd exhaust out the side like this instead:

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(Excuse the quality of the image... an artist I am not!)

Is exhausting out the side of this custom hood a problem? I only ask because every commercial unit vents out the middle top. It's a pretty small unit so I'm hoping it would be ok. I could see going out the side problematic if it was, say, 4 feet long.

It's basically a box without a bottom, but with a small 1" or so lip all around the inside bottom to catch condensation and a drain in the corner. Total distance from the custom hood to the outside is about 4-5 feet.

Does this make sense? I would simply drill 4 holes inside the "roof" near the corners and bolt it directly to the ceiling and then silicon caulk over the bolts to ensure no leakage.

Hopefully that would provide enough airflow. Unlike regular range hood fans the Vertex inline fans are supposed to be very good with static pressure meaning that smaller diameter duct and turns isn't going to severely reduce the CFM output.

If the airflow's not enough I could increase the wall hole diameter from 4" to 6" or exhaust out the other 4" hole too. I really hope neither is needed.

The other thing is that the hood doesn't even need to be stainless. Any sort of non-organic material will work for a hood (acrylic, formica, etc),
since you don't need to be concerned about flame/heat/grease from a grill top. I could build something temporary myself to see how it performs first.

Kal
 
An update...

After much tinkering and thought I decided I don't really have room to vent out the hole on the right (same side of the room as the sink and kettles) because of the sink goose-neck arm. So the Vortex 400CFM fan has been installed to vent out the left side hole and the right side is a fresh air intake now (plugged up in the picture below):

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With the tiny size of the room I thought that maybe just running the fan like this would be enough to keep moisture out of the room so I boiled up 10 gallons but after 20 minutes the walls were already completely dripping in and around the boil kettle so some sort of condensate hood over the boil kettle is needed.

My plan now is to get a custom stainless hood built from a local shop. It'll have a drip lip too with a drain into the sink. Before doing that I wanted to test out the size/shape to make sure it vented properly. So I built a temporary one for $20 out of pink foam:

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The test hood worked extremely well. It's 5' long x 1' high x 2' wide. Walls stay completely dry. 99% of steam goes where it's supposed to go. The control panel eventually goes on the wall out of the way of course...

The only issue is condensation build-up in the exhaust vent and the Vortex fan. With a screw removed from the bottom of the fan it drips every second or so so there's a lot of condensation. The little black compartment on the side of the fan where the power cord goes in also had water in the bottom of it (it seeps in from the inside of the fan). Not good I would imagine since it houses all of the electrical connections and a capacitor. I thinking I'll need to seal it up nicely and let condensation drip out the bottom of the fan into a bucket of some sort.

I'm still concerned that the Vortex fans are probably not rated for moving steam like this however...!

I'm also wondering if I'll have enough room to stir and maneuver with a large hood like this over all 3 pots (including the MLT which will need to be stirred during dough-in). Wondering if I should just get a smaller hood made that *only* goes over the brew kettle. Any thoughts are appreciated.

Kal
 
If you're getting a hood made they should calculate all this for you. If the person making this knows what they're doing you can tell them how long and tall your hood needs to be and they can design it so that it works better. It's not all about CFM (quantity of Air), you also need to look at FPM (speed of Air).

The manufacturer of your hood can calculate the speed that they need to move the air to effectively pick up the steam. I used to work in the sheet metal duct industry and have made lots of these kitchen/exhaust hoods. It's all about the opening in the bottom of the hood. Say you need a 10' long hood, well they will basically weld slats in the bottom of the hood and space them evenly (reducing opening size) to move the air at the speed they need. (hope this makes sense)

Also 4" pipe is pretty small to move 400CFM and I don't know how much static that fan will handle, but it could really be choked out and slowing down way to much to move the steam out fast enough to prevent it from turning to water in the duct. You should definitely look up the stats on the fan and give them this info. A duct calculator will give them the static pressure. I may actually have one at home that I could look at for you later. You may need to step up the pipe size.

Insulation will also help the condensation.
 
You might use a filter like in restaurant kitchens. They are meant to catch airborne grease, but the same idea should work for airborne water.

If the back of the hood were lower than the front, with the sides angled, the water could collect on the filters, condensate and run down toward the back into a channel that drains into the sink.

If you search for hood pics, you will see what I mean. Or ask to tour a large restaurant when they are not busy.
 
Thanks for the ideas guys!

Insulation will also help the condensation.

Interesting. Never thought of that but it makes sense: Helps keep the water from condensating as soon so more of it should escape the house as steam. Very interesting.

Some comments:

If you're getting a hood made they should calculate all this for you.
Yes, a good place will build/sell you what you need but this fan is reasonably small for this size hood but it seems to work just fine. I will ask them about it however. I didn't want to spend $500-800 on only the exhaust fan however not to mention that I don't really have room for it. The Vortex ~450CFM fan I'm using I'm told is very good with static pressure. It has 6" openings and everything is 6" except for the last foot to the outside (which is 4"). In tests it's able to exhaust the room very nicely during a full 10 gallon boil.

angle the front out somewhat? - for room to stir.
I thought of making it slanted but see the pictures above: I need to evacuate out the front as in the pictures. I can't do it out the back or the top. So slanting would be difficult to do I think.

You might use a filter like in restaurant kitchens.
If I used grease filters as is used in a regular grease hood it would work but they'd have to be installed on the front (closer to the operator) which I'm not sure would fit or work right. But it may - it's interesting thought.

I've been talking to these guys here: FASTKITCHENHOOD Fully Stainless-Steel Kitchen Hoods

I got some quotes on their heat hoods but the possilbly of using one of their grease hood looks interesting actually. Or a combo of the two. Just something to catch some extra condensation.

I'm also considering not making it 2x5' but 2x2' to only cover the brew kettle. 2x5' looks nicer though. ;)

Food for thought. Thanks guys.

Kal
 
My expertise was mainly in fabrication but I did pick up some knowledge of air and ventilation. We mainly worked in dust and smoke collection and an occasional kitchen hood. Obviously steam only, is a little different but I was thinking.

What if you built a larger box to connect directly to the inlet side of your fan? In the bottom of the box you would need to put a clean out or drain door. My theory behind this would be that the steam would move through your 6" pipe at a fast rate and would slow way down once it hits the larger box. Causing the moisture to fall to the bottom of the box. After cooking you could open your drain door and allow the water to run out.

We did this all the time in dust collection. It was called a cyclone effect. You had to determine how fast you needed to move the air in order to move the dust. The dust would be carried back to another chamber in which the air was moving much slower and fall into a collection bag or barrel.

This may be a crazy idea, I don't know. I haven’t worked with steam much other than kitchen hoods and they mostly had grease filters and the fans were set up to handle grease and moisture.
 
Earlier this year I asked about using a "chimney" on your bk like major breweries do in order to evacuate the steam. That link is here: https://www.homebrewtalk.com/f11/cone-chimney-bk-112972/

It is relevant because I think you can solve your condensate problem with a condensate trap. ClaudiusB shows his setup here:


https://www.homebrewtalk.com/f11/cone-chimney-bk-112972/#post1246241

Later in the thread there are some crude drawings/etc and discussion about condensate traps. This was in regards to a chimney, but I believe just as pertinent for hoods.

Just my .02




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