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Hello
After I checked the low pressure lines of my ac compressor they are already insulated from the front evaporator to the rear one
Given the fact that my brand new car has poor ac performance inspite of good pressure in the high and Iow pressure lines. I decided to install 12 inch auxiliary fan in front of the condenser
so total fans will be 3 . One belt driven and 2 electrical .
I want to wire the auxiliary fan so it turn on and off with the stock condenser fan .any idea how to do that
By the the way my car is mitsu pajero and ambient temp is 50C
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I would tap in right at the connection before the stock fan this way power goes to both at the same time. The only issue you will run into is the second fan might cause the fuse to blow. If that happens, experiment with lightly higher amp rated fuses. The fans don’t pull a lot of amps so it shouldnt really be a problem. Let me know if you have further questions
Thank you
Actually I will instal Spal high perfermance 12 inch fan which might draw up to 21 ampIf I’m not mistaken I should ground the fan and attach its power wire to the blue wire in the photo
The stock condenser fan rated at 25 amp .I think if I added 21 amp fan that would frys that fan power wire ( blue wire)
I’m thinking in adding external relay but I don’t know how to make the computer activate the relay of both stock fan and aux fan at the same timeYou can go to the wire before the stock relay (after the switch and and split it in 2 and run parallel circuits controlled by one switch with a relay and a fuse for each fan.
Brand new car? Look at how dusty your fan is in that picture, that’s ridiculous. Based on it being a Pajero, 50°C, and the look of that dust, I’d say you’re driving around the desert in that thing. I’d be willing to bet that the condenser is so dirty that it’s not transferring heat efficiently and needs to be cleaned. Airflow is irrelevant if the condenser is insulated by filth. It doesn’t matter how much dust is around, condensers need to be clean to work properly and you may have to get in the habit of washing the thing out on a regular basis.
As for running your fan, you should be using a aftermarket 30A Bosch-style relay that supplies fused battery power directly to the new fan. Tap into the existing condenser fan wiring to activate the control-side of the relay (which draws less than 1 amp) whenever the stock fan powers up. That way, you can avoid overloading or interfering with the existing condenser fan circuit and fuse. I highly discourage the approach of running the 2nd fan with existing wires and putting higher amperage fuses in. Big time fire hazard, especially in that heat you’re in.
You’ve got the wiring right in your picture. The highlighted wire is ground that is supplied by the PCM to activate that relay. If you used that wire, you would replace the control-side ground with a power feed. I wouldn’t recommend doing that because then the PCM will have to have additional current from your aftermarket relay grounded thru that terminal and who knows if it’s up to the task. Do it how you’ve drawn it to be safe.
I still think you should clean the dirty condenser first, though. I’ve fixed several weak A/C complaints by doing only that.
[quote=”Fopeano” post=145466]I still think you should clean the dirty condenser first, though. I’ve fixed several weak A/C complaints by doing only that.[/quote]
I bought my car from the dealer about 4 months ago.I noticed its poor ac performance since the first time.then I downloaded US version of the service manual (Mitsu Montero 2006 ) , checked the pressure and performed performance test.
Everything were upto specs!!!
Then took it to the dealer because it is under warranty,but the technician there said he added some amount of refrigrant to the system.!!!!!!!!So decided not to trust them and do everything myself as possible.It dose not make sense that I have to clean the condenser every 4 months .
Have you tried cleaning the condenser yet?
In your first post, you said the car was “brand new”. Now you’re saying it’s a 2006, which is at least 9 years old. My recommendation to clean was based only on the picture you posted of a fan and radiator covered in dust. Dust comes typically comes in from the front, and the condenser is in front of the area pictured. You say it’s been the same lousy performance since you bought it, maybe you were sold a car with 9 years worth of dirt in the condenser as opposed to 4 months worth. The tech at the dealer could easily have put some refrigerant in because he was at a loss of what to do because he’s not strong on AC like I am, and that’s typically what one does if it’s not working well and one does not understand why.
I would assume that water is scarce in the desert but surely in a city large enough to have a Mitsubishi dealer, I’d expect you to be able to find access to a garden hose. BTW, don’t pressure wash it, just flushing it with a garden hose and spraying some degreaser in there and rinsing it out will do all that’s needed. Post up a picture of the condenser taken from the front looking thru the holes in the bumper where the airflow comes in. Lets see what it really looks like.
By the looks of the fan the condenser and radiator are most likely dirty.
this may help to get the airflow back without the extra fan.Oops ! :ohmy:
I am sorry, but English is not my mother tongue ,so you may get confused 😳my car is 2015 bought it 4 months ago ( new not used- odometer zero)
I used the 2006 montero SERVICE MANUAL because I could not find newer version . I think the car has not been changed since 2006
Hello again !
Here is an update
I have installed the fan , but I noticed that when the fans turn on , the dome light become weaker for a second then return normal that made me worry about the alternator. Am I overloading the alternator with this aux fan.Thank you
That’s more likely a characteristic of the specific fan that’s installed. See any electric motor, including a fan motor, draws many times more amperage/current during startup than what’s used to keep it running once it’s at operating RPM. This large amperage draw momentarily causes a voltage drop in the whole system, resulting in your lights dimming.
The factory fan motors are quite expensive largely because they use superlight fan blades (lower mass makes it take less power to get it going), smoothing condensers (smooths out the abrupt current draw by acting as variable resistor), and generally higher efficiency motors than a aftermarket fan. That is why super cheap fans on economy cars are still in the $250-$350 USD range even when good aftermarket fans can be had for as little as $100. On luxury cars where no dimming or noise at all is tolerated, they’re frequently $800+. With the aftermarket fan, they want them to be affordable so they will sell a lot of them but also want them to work well at providing airflow so that buyers of them will recommend them to others. People are usually putting those things in race/custom cars where the startup draw/dimming is not considered an issue (even if it’s noticed), so the expensive options that car manufacturers use in their fans are not worth using when considering the big picture for the aftermarket manufacturer.
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