digitaltrucker

wpt 965
wpt 1078

Both are Motorcraft parts

www.rockauto.com

Or I am sure STeve at tasca can help you

stangman39

Hi all,
Wanted to give an update on my results so far. I really appreciate all the hard work so many of you have put into this.
First thing...is the IRT cooking digital thermo I got from Amazon...I've tested it twice in ice water now and the lowest it gets to it 36.8. I looked and looked and can't find a way to calibrate it...so I'm figuring now all my test readings have been about 4-5 degrees cooler than the thermo has said. All my numbers below are accounting for this adjustment.
Last week I also took my truck into the dealer for oil change etc. and had them look at the AC. They evac'd the system and refilled. They said it was about a pound low.
I got a 680 resistor set up from Rymax101 and since then in 90-96* temps I'm seeing 38-40 out of the vents which I'm happy with. Prior I was abount 43-45*.
I have also found once the cab is cooled down and I have the fans on 3 bars and recirc I get my lowest temps.

jlinville

I did a rough install this morning until I get it dialed in. My voltmeter has a setting for 20m ohms, so I could only dial it in to the hundredths. I set it to .35 or roughly 350K. I'll have to fine tune it with another meter.



Although it was only 76* this morning, it usually spits out about 43* tops (or should I say bottoms) this early in the morning. 38.3* is a great improvement. It will get tested more later today.

stangman39

Sorry for sounding dumb but what is the reason behind getting the additonal harness posted above from Ford?

jlinville

plug and play installation!

Oldsmuggler

Forgive me for my ignorance. I've been following this thread and I'm impressed with the knowledge and ingenuity that many people have on this subject. I'm no where in your class of expertise but I thought this seemed easy enough for me to even try. My a.c. is fine but I thought how nice it would be if I had temperatures in the high 30's here in south fla. I bought a temperature gauge and tested it in ice water, then went to radio shack and bought several packages of assorted carbon film resistors. 1/2 watt. I started out at soldering a few together to get me at 514. I did the hack and temperature dropped to 32 degrees. I realized that is too cold for the system so I have been soldering the different resistors together to increase the numbers. I'm up to 1600 but my a.c. will still drop to 32 degrees, I can't seem to find a sweet spot of high 30's. It was 95 degrees out yesterday. I also get these readings with the a.c. not on recirculating. When I reach under and pull the resistor out the a.c. will begin to climb in temperature and return to low or mid 40,s depending on outside temperature. I can't seem to figure out what I may be doing wrong. Does having a 1/2 watt compared to 1 watt have an effect? Or should I just keep going up in numbers on the resistors? Sorry for being so ignorant.

stangman39

Cool. Can you explain how you installed it and set the resistance?

jlinville

Well, not to sound like a punk, but I read these threads and gathered my info from them.

digitaltrucker has had pretty good luck with the 345k(ish) mark, so that is close to where I started. There seems to be a pretty large variance of numbers that are working for others though. I am using a potentiometer because of its adjustability. I took a chance on buying terminal connections that fit the factory connections. When I got them, I wired them up to the potentiometer that I set at about 350K and plugged it into the factory connections. Now I can fine tune it.
There is also a simple wiring schematic posted (#554) by cwdaniels that explains the connections.
Hope that helps you.

BosAg

Are you using 514 or 514K (514,000)? I think there is a big difference.

RLXXI

No, the amount of current flow capability is where you want a higher/lower watt rating, since this particular circuit is carrying little to none, the only thing that matters is the resistance value.