SharkSkin

THe "WTF" was, I don't think this is the right relay for the application.

69gaugeman

That diagram shows both styles of relay that they offer in that same package. The one on the left is the correct one with single coil.

SharkSkin

Ah, OK... I guess I got confused somewhere along the way, thought it had to be DPDT.

steaditim

On the left is the new 5A relay that I got from Radio Shack. On the right, is the old one from the AC control unit.


Tim

69gaugeman

The two relays are the same current carrying wise. You could probably get the original at electrosonic. you can take that one in or look at the spec sheet posted earlier. Also I think future electronics might have it.

69gaugeman

you can see the spec sheet for the new relay here http://www.sunhold.com/tna.html

by the way there aren't any more radio shacks in Canada any more are there?

At least not down here anyway.

steaditim

Hey 69gaugeman:

Thanks for your input. I'd really like to replace it with something more beefy. The 2A was apparently underrated for the application and who needs another burned out AC compressor. Some guys are putting in 10A relay in place

You're right about Radio Shack. I picked up the part some time ago.

T

69gaugeman

If you want something more beefy you will need to get a different one. Let me see if I can find something for you.

steaditim

Thanks, I would appreciate your thoughts

69gaugeman

this relay will work. They show none in stock but you could call them to find out delivery. 4.93each and good for 8amps

69gaugeman

Use this link to contact Electrosonic

steaditim

69gaugeman

Thank you kindly,

I'll let you know how it turns out.

Tim M

SharkSkin

Tim,

Something else you might consider -- you could replace that relay with an equivalent unit, then mount a serious power relay(like your horn relay for example) elsewhere that would do the work of actuating the clutch. That way you won't have to hack up your HVAC controller, and the big relay will hold together a LOT longer than anything you can squeeze into the controller. Also, you could mount it somewhere that's more accessible, just in case.

ew928

I've seen 2nd higher powered external relay wired to intercept the factory relay signal
by the underhood jump point. Just pick the rating of your choice. No need to
worry about dimensional constraints of the climate control box.
Easy access to replace the external piggy-back relay instead of having the pull
the climate control head.

Ernest (NYC)

docmirror

I disagree that this is the same rating as the original relay. My clutch relay failed just as all the others failed, and I used an aftermarket relay exactly like this one as a replacement.

You will need six pigtail wires, about 8-10" long, of 20-22 Gauge. Think of it as three sets of two wires. One set for the coil, one set for the + supply sometimes called the wiper, and one set for the NO, or picked contacts. coil is pins 1 and 16 from the board. wiper set is pins 5 and 12 from the board, and picked pins are set 8 and 9 from the board.

The coil connection is obvious and goes to the wires all alone on the end of the new relay package. Polarity is not important. Connect to the AC board at locations 1 and 16.

The + supply wires go from AC board, (middle set of pin location 12 and 5 from old relay) to the middle group of pins on the new relay which have the bent arm that looks like a wiper. Pin holes for pins 9 and 8 of the old relay(location 9 and 8, far left in post #19) will connect to the Normally Open pins of the new relay which are near the edge, furthest from the coil pins. Note that in post 12, pins 8 and 9 are clearly NO, as is typical of relay logic.

If the wiper and NO set are reversed, it really won't matter in this application. Just don't use the NC contacts and you will be fine. Once the wires are in place, I just glued the relay to a metal post behind the AC control head, and pushed the AC head in normally. Tin the wires with solder, and push them into the board, then solder from the side that has a small copper ring for good connection.

The NC (normally closed) set of pins are not used. Operation is: When AC button is pushed, and temp at the sensor is higher than temp set on the slider, the coil circuit will energize, causing the relay to pull the wiper pins from their normally open position to closed, completing the + circuit to the AC clutch and pulling the clutch closed, thus turning on the AC pump. When the temp bulb in the evaporator reaches a determined temp, it will open the coil and release the clutch. This will cycle as long as the temp sensor is above the slider temp, and the AC button is in.