Anyone replace a Faulty J7 Connector on Sta-Rite Max-e-Therm?

[dnspade]

Had a power surge of some origin. Have replaced fuses and control board and have now nailed it down to an intermittent/faulty j7 connector interfacing 24v and control wiring to the board (behaves same way with both boards). I know I have good 24v power coming from the xfmr and can get the connection to happen by exerting force on the connector. However, a new wiring harness is $150 and a lot more work than I need or want to do.

Anyone out there face a similar problem? I am having trouble tracking down a replacement connector, so any info on the 4pin white connector would be appreciated as well. Thx

[Charlie_R]

Is it possible for you to post a picture of this?

You can use a pic hosting site (picasa, photobucket, etc), and link the image here. I do have some small experience with balky connectors on other non-pool equipment, but need to see what I'm dealing with.

[dnspade]

Thanks for the response and the interest in helping. I did solve the problem this morning and will post the solution here in case anyone is searching for a similar answer.

The basic symptom was that the board (and thus heater) was not working at all. Following the diagnostic flowchart in the owners manual will lead you to believe that the control board is faulty. However, after swapping out the control board, it still was not operational. In both "before" and "after" situations, an intermittent situation was observed in that the board would power up when applying some sideways pressure to the J7 connector while on the board. This J7 connector provides the board 24v power, as well as controls the power through any timer/etc hooked up through the fireman's switch circuitry. The presence of 24v and the timer circuit was verified through simple continuity tests. Examination of the j7 connector did not reveal any obvious damage.

WITH THE POWER OFF - BOTH THE TIMER CIRCUIT AS WELL AS ANY ELECTRICAL CONNECTION

Removed one pin/wire at a time from the connector (too lazy to label the wires which do not say which pin they go to). The pins insert into the connector and are formed sheet metal with spring loaded tabs on two sides. One side is the retention mechanism which you can see when it is seated in the connector (a golden rectangle barb that clicks into place and prevents it backing out). On the opposite side is an angled tab which is intended to make contact with square pins on the board that insert into this female connector. It does not encircle the pin, just makes contact on one side.

I removed the wire/pin by depressing the retention tab with a jeweler's flat head screwdriver and pulling on the wire. I examined each pin and did not find any discernible damage or corrosion. I then "expanded" both the retention tab and the contact surface by taking the jeweler's flathead screwdriver and prying them upwards. These can be moved significantly, as insertion back into the connector body will force the pin into compliance. However one should take care and be delicate with this prying as you do not want to break the pins.

After repeating this once for each of the four wires, I reinstalled the connector on the board, fired it up and it worked fine. I can not conclusively determine the root cause, as the connector had not been disconnected prior to the failure. The only guesses are either that the connector/pins were marginal coming from the manufacturer, or, the overpower condition that burnt my two fuses created enough heat in the connection temporarily to deform the pins, degrading the contact.

Hope this helps someone in the future, as this potential failure mode was never outlined. Maybe I was just "lucky".

[Charlie_R]

You did essentially what I would have suggested as a first option. Glad you figured it out!

[dnspade]

Any idea what would cause that? I am mystified as this was not a connector that was pulled on and off a lot.