View Full Version : Fan Speed Controller

01-06-2004, 10:33 PM
I want to fit a fan speed controller to a freezer unit running on R404
Can a member advise and on the best way to achieve this....I am thinking of using a pressure stat.

What about the settings. If I take todays conditions into account........Ambient.........19 C. Head pressure with both condenser fans was around 150 psig. I think Im overcondensing.........Need to come up to around 200 psig I think

02-06-2004, 12:46 PM
yep, 150psi seems to be a bit low. You should aim at min. 170 tot 180psi at all time. You could use a SAGInoMIYA/DANFOSS RGE fan speed controller. You can fix it directly on your condensor and it is available in both single and three phase versions.
Other solutions could be ELIWELL FASEC, ALCO FS or JOHNSON CONTROLS P215 and P255.


02-06-2004, 01:52 PM
hi abe.

if you look carfuly at the electric diagram of that condensing unit , you will see that there are two contactors marked K51 and K52.

although I entirly agree with niko, I will give you an other option.

install a high pressure presostat and run the phase from one of contactors coil through points 1 and 4 .
set it on 210 psi more or less and set the differential to the minimum and and head pressure will be maintaind.


02-06-2004, 05:46 PM
Thanks Chem.........thats what Im doing
I will post a pic 2 moro..........System working beautifully
Thx for all your help