Alan

Good - yes I meant Short Circuit (SC) and Open Circuit (OC) as Otto noted.


I think that would be a very good idea, the input will be another high impedance input for sure so you don't need to worry.

However the TC temp switch connects to ground and the pressure switch also connects to ground. So unless the sense of that input is swappable I assume it will want a high trigger so you'd need to use a relay to invert & combine the signals - easy though.

Connect both switch triggers together (neither is used elsewhere) connect to the new relay terminal 85, connect 86 & 30 to ignition power and 87 to the sense input on the new fan controller. Whenever either the pressure switch conducts OR the TC switch conducts the input will go high to trigger full fans, neither should happen too often. You could even also connect the intake temp switch in parallel too - it works in the same way.

Alan

MainePorsche

What does one say...
Thank you Alan.
You make these matters easy by definitively eliminating doubt.
What does one say to such Mastery on these matters that is given to our Forum...

MainePorsche

This will be rather straightforward by taking the all the sender feeds (TC, intake, frigen) right at the controller into the relay. The TC and intake feeds are already joined to connect at pin 3. Won't be difficult to have only one line channeling to the engine compartment to connect to the new fan controller.

Last question Alan (on this matter).
You say the TC and frigen switches connect to grounds, and these triggers go to 85. The intake can go there too, but in parallel - why could it not go directly to 85 as well as the other two ? The intake switch connects to ground as the others. All then would be combined and inverted, or am I misunderstanding something ? They are already joined at the controller.
Thanks,
Craig

Alan

Yes - when I say in parallel I mean connect them all together on 85 so all the switches are in parallel - very easy.

Alan

MainePorsche

Thanks again.
It's obvious my electrical prowess is not.

MainePorsche

Interesting.
The 'generic' dc AC switch activates fans at 50% via pin 14. Optional set up is attaching pin 12 into the mix to get to 100%. Might combining TC, refrigerant sensor, intake sensor through pin 12 give additive protection to these systems by boosting to 100% when tripped ?
I don't know what kind of amperage would be needed to activate this 100% pin, but could call the fellow and find out.
Your thoughts ?

I meant to add this as a post, and it came out as an Edit as seen above.

Stand to correct myself.
Pin 12 on the dc controller adds 10% on AC activation.
Pin 14 on the dc controller adds 50% on activation.
Brian Baskin at dc controllers says there are 2 more pages of instructions that have not been included as of now, but are under construction as an app-note.
He says there are several temp overrides that can be used.
__________________

Captain_Slow

Update: I won't claim that the fan issue is solved, but it's been about 2 months without a problem (both fans work fine now). I swapped the fuses left and right and both fans worked for a few weeks. Then the right fan would cut out intermittently. Pulling and reseating the fuses returned the fans to normal. So I decided to look more closely at the panel sockets. The left socket showed some evidence of heating in the past. I thought of everything from fan problems in the past burning fuses to corrosion on the socket contacts causing it to heat up. I applied Deoxit three times to both fan sockets and worked the fuses in and out in between applications (fuses are new). It's been 2 months and the fans continue to work perfectly (now I'll jinx it by clicking post).

Mrmerlin

the deoxit removed the corrosion that is preventing a solid contact, it takes a few hours to work use it on the fan plugs as well.
NOTE use an IR gun to see if the fuses are getting warm if so the female side may need the pins to be bent closer together