like morning YouTube so I've got to do a little bit of work on my attic fans
here unscrewing here apparently some bees or Yellowjackets or something built up I messed
up up in the vent here I've got the garbage can here to catch all the stuff I think this fell
down in here yeah here we go clear it out so it's blocking my air flow a little bit
this is a four by nine inch oval duct think these were installed when the house
was built and there used to be a flue for an in-wall gas heater that was here
some point before I purchased it these two heaters were removed in a central forced air heater was
installed so whoever installed the forced air heater removed the in wall heaters and they
just left these two holes in the roof so back in 2013 I decided to come up here and take a look at
the Attic I had never really been up here much at all it was very uncomfortable because it would get
well over a hundred 40 fahrenheit up here in the summer anyway so it was up here I was working on
some insulation projects up here and putting down some plywood so I could get over and access things
can't these openings here and it's like you know what those are about the same size as
a 120 millimeter case found a piece of 1 by 8 lumber and I marked out a hole and cut a kind of
a tapered hole here so it's it's about 5 inches wide here and then inside it's about 4 inches
wide and I set that jigsaw blade at an angle so I basically cut out a hole to match the taper there
and that lets these fans blow air straight up out of those holes so yeah this makes a really nice
ducted output for these fans and let me get this one back in place here I usually come up every
couple of years and use a toothbrush clean off the blades but there there's no loose dust on there so
I think that's good I don't know how you pronounce that if it's silence or silent X so these are
their 120 millimeter case fans they're rated at 74 cubic feet per minute free air flow so these
fans were installed in July 2013 it's now july 2019 they've been running for six years they're
powered by solar power 12-volt DC so the house has a metal tile roof and the reason I installed
these fans was because they fit these holes that exist in the roof so when I was thinking
about ventilating the Attic I initially looked at some of those whirlybird wind powered vents
those need about a 14 inch diameter cutout in roof and with that tile roof it's not easy to do that
you probably have to hire a competent roofer that's got experience working with tile roofs
to cut the hole install the fan and then seal it up so it doesn't leak that would probably cost
about five hundred dollars to do that and then I also looked at some of those solar attic fans
which mount up on the roof they have a solar panel on top a fan in the middle and then the
opening in the roof and those need about a 13 inch diameter cut out I had 9 inches here not
13 in the other problem with those solar fans and they only run when the sun is shining they
don't have any batteries to them this fan will run all night if it's hot up here so these fans they
really do work turn the thermostat down a little bit get them to kick on here up there they go I
just bumped the thermostat and it turned on so I was informed by a knowledgeable viewer that these
kind of fans don't move any air they are a total joke and they don't move air at all that must be
some sort of anti-gravity vortex thing going on there I don't know how that paper is being held
up there but that looks like it's working there and here's my airflow meter this is a Mannix D CFM
eight nine zero six take a air measurement here okay there we go we've got 356 feet per minute
airflow so I programmed in the size of the duct there okay so that's the airflow we get 89 cubic
feet per minute and there's this pair of fans there's another pair of fans about 12 feet that
way and then on both gable vents there's another pair of fans on each gable van so that would be a
total of 360 cubic feet per minute airflow and the attic is about 1,200 square feet and the average
height is about two feet it's about four foot peak in the middle and then goes down to zero at each
side so you've got about 2400 cubic feet of air up here 360 CFM a ventilation gives 9 air changes per
hour which is maybe a little short I've seen recommendations of about 12 a CH for an attic
there's a whole section of the attic where there's no ventilation at all it's off to the side so in
the main attic here we've probably got about 12 a CH because about a quarter of the attic is off to
the side and I would like to add some ventilation over there I'll probably add a gable vent because
that part of the house there's like no ventilation at all this may not be ideal but this is what
I have to work with and right here this is the thermostat an adjustable temperature thermostat
with fire stat so this has both the thermostat that you can adjust the on/off temperature and
then it also has a low melting point fusible link that will melt and open if there's a fire up here
that gets above its temperature and that will shut off the fans in case there's a fire this
is the sort of thermostat you use to control attic fans just I happen to be using it on 12-volt DC so
I showed you in the earlier video how I added a snubber Network to the contacts in here to help
with arcing because it's switching DC voltage instead of AC voltage now these eight fans that
I have in here only draw a little over one amp I think it's 1.1 amps at 13.8 volts so they're
really not a high power draw so I could have one large fan that moved 360 CFM or I could
have eight smaller fans that move about forty five each now some people will of course say
that's stupid idiotic you shouldn't do that well here's my whole house fan this is a commercially
produced whole house fan from airscape fans in Oregon and instead of one big fan they use for
smaller fans too that blow this way to that blow that way on really hot days I use this to cool
off the attic so far this year it's it's middle of July I've used this I think five days out of the
year the rest of the year the 12-volt bands do the job now these are brushless motors the fans it for
the attic vents are DC brushless motors they just happen to be smaller than these here's four I've
got eight of the little fans and let's go take a look at one of the other setups here so here's one
of the other fan pairs over here this one I had also a bit of debris in there that was blocking
the one fan so let me grew it back in place here and let's get a airflow reading over here
yes there we go 381 feet per minute get around here where I can hold this thing so we can see
the display 381 and that's 95 CFM I think we're getting close to a hundred CFM per pair of fans
which is 50 CFM each and they're rated at 74 so about two-thirds of of what they're rated
out yeah those are working just fine so again this was an existing hole in the roof that I
took advantage of and there's really no bigger fan that I could have put in there because it's
four inches wide and then nine inches across on the duct that's how big it is I can't put
a bigger fan in there because it really wouldn't work and these are quite silent you'd hardly hear
them when the outer door is closed you don't hear them at all and you can see down here is
one of the other fan pairs in the gable vent and then up here this is my LED light strip there's
three of these strip lights five meters each up here these have been running in the Attic hot
summer temperatures up here so not a single LED chip has burned out and the reason I like these
is because they're safe to touch they're cool you can't get a shock on them the fans run off
a solar power it's all solar powered up here I'll put a link to the video where I did some
temperature testing up here so I'll put a link to that video up in the upper right corner and
you can check that out the real advantage of these fans they're not super powerful I will
admit these are not like your Hollywood movie set fans that blow your hair back you know like
you see in the movies these just move a little bit air 360 maybe 400 CFM they are not quite
enough to keep up with the temperature I mean the temperature in the attic rises slowly during the
day by sundown the temperature up here will be about 20 degrees higher than the outside
temperature but then these run off of batteries and at night they keep running until the Attic
cools down to about 70 Fahrenheit and then the next morning once it warms up above about 75 the
fans turn on again temperature slowly creeps up during the day and then at night it drops down
and it's that overnight cooling that resets the temperature up here every day so the other nice
thing with this setup is I can service these fans from inside the Attic I don't have to break out a
ladder climb up on the roof and exposed myself to falling off the roof or damaging a tile or
whatever I can do this from inside the house even if it's raining or dark I can come up here
at night I've got light I can service the fans that's probably about the motor door for time
I've had to even touch these things in six years so they're very reliable so yeah if you have any
questions about that go ahead and post up in the comment section below y'all put some of the other
fan videos over here on the left side you can check those out and as always thanks for watching