Recommend a Source for Squirrel Cage Fan?

[OneLapper]

Ok.  As some of you might know, I hate the look of roof air conditioners.  Yup, I've read every post on the pros and cons of roof air.  For a couple of years I've been on the lookout for a basement AC system and nothing appetizing has come up.

All of the above sent me in the direction of marine air conditioners.  The more I read about them, the more I liked them.  After looking for over a year, I finally found the exact model I was looking for on Criagslist, a 4 year old Webasto FCF 16k btu AC with heat pump.  I had a few hours of soldering and heat shrinking to do to get it going because the seller cut every wire when removing it, but it runs perfectly!  Man, this thing is quiet!  I mean really quiet.  Best part is, I will no longer have a bucket of water dumped on me when I shut it off like the Dometic Peguin roof air conditioner does to me.  Nor will I need to put a towel under it.  Nor will it ruin my new wood floor.  So there, Dometic.

Here's a picture of the unit.  I had to use the kids project table because it was -15 outside this morning, so the garage was not a hospitable place to work.

 

For testing I'm using a 12vdc pump, but I'll be using a Taco 007 pump for the install.  I'm going to use this heat exchanger http://www.ebay.com/itm/18x18-Water-to-Air-Heat-Exchanger-1-Copper-Ports-/141565717742?hash=item20f5f96cee:g:JCUAAOSw5dNWr9Pb

To use with the heat exchanger I need a 115 volt squirrel cage blower that flows about 750 cfm at max speed.  I can't seem to find what I'm looking for.  Where are you guys buying your fans?

BTW, in AC mode it blows 34 degree air from 85 degree water, and in heat mode it blows 110 degree air from 40 degree water.  I also really like the "Auto" mode:  you set the temp you want and the unit will switch between AC, fan and Heat Pump automatically to maintain that temp!  It also has a wireless remote for us lazy drivers.







I'm going to install this unit and test it out this season.  If it works well, I'm going SANS roof units and will buy a second marine unit, or a single large unit.  This one is 115v and has a 550 cfm 3 speed blower on it.  It's rated at 100% capacity with water between 40 and 90 degrees.  The triple pass heat exchanger won't be as efficient, but it won't be far off.

I realize and expect lower cooling capacity when it's over 90 degrees outside.  This was a concern until this summer when my Penguin would shut off the compressor when it was about 95.  At least this unit won't be sitting on top of the roof baking in the sun!

[muldoonman]

Grainger Industrial Supply.

[dtcerrato]

I love grabbing squirrel cages from dumpsters, old heating units being trashed. They're rather easy to come by. I have them all over. Also love to move air. House, coach, truck, where ever....

[kyle4501]

Nice rig. I hope you can get fans that are quieter than the ones Newell used. They are louder than the generator.

Grainger will have one that will work, but will be spendy. However, you can get an idea of what size to get.

I would then check with a HVAC installer for a fan from a take out. You may need to replace the motor to get 115v.

A fan curve is needed to know the pressure & cfm capacity. A fan's design will determine the hp required to develop a pressure drop, then the amount of power needed to move a volume of air.
You can damper down the fan intake to reduce air flow & the power used by the motor. But, you can't do anything to change the pressure drop across the fan or the power to do that.

So, you will need to be sure to get a fan with sufficient pressure capacity and excess air volume capacity to have success.

[muldoonman]

How large of water supply to keep that puppy cool at 90 degrees. Would have to be big even with heat exchanger. Boats have a whole lake or ocean to cool.

[OneLapper]

Nice rig. I hope you can get fans that are quieter than the ones Newell used. They are louder than the generator.

Grainger will have one that will work, but will be spendy. However, you can get an idea of what size to get.

I would then check with a HVAC installer for a fan from a take out. You may need to replace the motor to get 115v.

A fan curve is needed to know the pressure & cfm capacity. A fan's design will determine the hp required to develop a pressure drop, then the amount of power needed to move a volume of air.
You can damper down the fan intake to reduce air flow & the power used by the motor. But, you can't do anything to change the pressure drop across the fan or the power to do that.

So, you will need to be sure to get a fan with sufficient pressure capacity and excess air volume capacity to have success.

Hey Kyle,

I'm on a steep learning curve with centrifugal fans.  There's a lot to them!  I have good specs on the water to air heat exchanger that I think will be sufficient, and I plan to go 200 to 300% over capacity on the exchanger and fan to keep the velocity of the air down, hence the noise.  No matter how I look at it, it will be an order of magnitude quieter compared to the two roof AC units I have now.  The compressor is nearly silent. You have to touch it to know it's on.  The blower makes all the noise, but since this will be ducted it should quiet the blower down.

Grainger has tons of choices for fan.  I'm hoping that someone can recommend one that they are using with some success, say with their generator radiator, etc.  I see that Ebay has the same brands for about 25% less than Grainger, so I'll likely source it from there. 

[OneLapper]

How large of water supply to keep that puppy cool at 90 degrees. Would have to be big even with heat exchanger. Boats have a whole lake or ocean to cool.

No water needed!  Well, it'll be a closed loop system using antifreeze like a generator using a remote radiator.  Instead of using a tube and fin radiator, I'm using a 12 gallon per minute, triple pass water to air heat exchanger.  The recommended flow for the AC unit is 6 gallons per minute, with 4 min and 8 max.  I'm using a 13 gallon per minute pump (adjusted for 5' head).  The flow rate, the size of the water to air exchanger, and the squirrel cage fan should all work out be 2 or 3 times the needed capacity to keep the marine unit at 100% capacity up to 90 degree air temps.  And by using antifreeze, it'll be able to create heat much lower than 40 degrees.  I'm no HVAC guy, but I don't see how it can't be at least as good as my crappy roof AC units which dump water, are noisy, and stop working when it's hot out!  I might be wrong, but at $350 for the AC unit, the pump I already had, the heat exchager is $120, and the fan $150ish, I'm in it for less than a new roof air.  Plus, I can sell the marine unit for $600 on Ebay, if not more. 

[RJ]

Mark -

I'm going to be pulling the two squirrel cage fans out of the condenser compartment of my 5C, since one of the two PO's tore out all of the engine components for the factory A/C.  They're powered by a 2hp, 24vdc, double shaft motor, so there's a lot of capacity.

I'm going out to the coach tomorrow, so I can photograph and measure them for you, if you're interested. 

FWIW & HTH. . .

[OneLapper]

Mark -

I'm going to be pulling the two squirrel cage fans out of the condenser compartment of my 5C, since one of the two PO's tore out all of the engine components for the factory A/C.  They're powered by a 2hp, 24vdc, double shaft motor, so there's a lot of capacity.

I'm going out to the coach tomorrow, so I can photograph and measure them for you, if you're interested. 

FWIW & HTH. . .

Thanks! Text me the pictures when you get a chance

[muldoonman]

No water needed!  Well, it'll be a closed loop system using antifreeze like a generator using a remote radiator.  Instead of using a tube and fin radiator, I'm using a 12 gallon per minute, triple pass water to air heat exchanger.  The recommended flow for the AC unit is 6 gallons per minute, with 4 min and 8 max.  I'm using a 13 gallon per minute pump (adjusted for 5' head).  The flow rate, the size of the water to air exchanger, and the squirrel cage fan should all work out be 2 or 3 times the needed capacity to keep the marine unit at 100% capacity up to 90 degree air temps.  And by using antifreeze, it'll be able to create heat much lower than 40 degrees.  I'm no HVAC guy, but I don't see how it can't be at least as good as my crappy roof AC units which dump water, are noisy, and stop working when it's hot out!  I might be wrong, but at $350 for the AC unit, the pump I already had, the heat exchager is $120, and the fan $150ish, I'm in it for less than a new roof air.  Plus, I can sell the marine unit for $600 on Ebay, if not more. 

Interesting to say the least. Might find you a moneymaker if it works out. Keep us posted as my 3 Cruisairs are giving me fits.

[kyle4501]

I don't seem to have any time for involved projects these days, so I look for easier solutions . . .

http://www.adventurerv.net/dometic-duo-therm-brisk-air-conditioner-13500-btu-p-30147.html

$437 + shipping. I got one for the Airstream trailer - worked great, low noise, & my favorite part was low effort required to install.   

Hope to see your successful install in person one day soon!

[TomC]

To cool my remote radiator on the 10kw generator (compartment is too small for radiator) I used a single inlet squirrel cage blower with a 2 spd 1/2 hp belt driven totally enclosed ball bearing fan cooled motor. High spd during the day, low spd for quiet night time. Grainger carries these, albeit is more expensive than what you paid for the A/C unit.
I hope it performs sufficiently. It wouldn't be good for me since temps out west regularly get above 90 degrees (highest I've been in is 108). But good luck with the project-I've often thought of using the marine units too. TomC

[RJ]

Thanks! Text me the pictures when you get a chance.

Mark -

Did you get the text msg with the pic I sent you yesterday?

[OneLapper]

Hi RJ, got your text, as you know.  hahaha

[OneLapper]

Why on earth are squirrel cage blowers so expensive?  It doesn't add up.