: 6-07_04012009.pdf
ead of the stock 40W just in case it was underrated. I measured the operati ng output current during cool or heat and it maxes at .6 amps when 2.0 woul d be the limit. I cleaned up all the sloppy wiring from the installation an d so far no blown fuses but with such an intermittent problem you never fee l like you got it for sure. The only problem I could find was during heat c all the red light would blink for 3 times indicating a problem with the saf ety pressure switch (enough gas pressure?). I temporarily bypassed the swit ch then it would latch and the heat would work fine. The only thing I can f igure is that it the unit tries many times to turn on the heat and the pres sure switch never makes the board commits suicide and deliberately blows th e fuse so that you have to call a service man???? Sounds crazy but I wonder . I'll replace the pressure switch and see if the problem ever returns. For now I have a bunch of 2 amp (instead of 5A) fuses on hand to keep from blo wing the transformer again. From the many web posts this seems like a commo n problem.
blows the xformer.
alled a new xformer and added a PTC fuse device in series with the secondar y just in case. A regular fuse rated for an amp or so above the xformer ra ting is a good idea. Also tie wrapped all the loose wires so none were ru bbing on anything.
And other times, it's just that the supplier of the part is making crap and it just keeps failing. I had that experience with a Sears de-humidifier. The fan burned out, so I bought a replacement one. It lasted less than a year. Then foolishly I bought one more. That one burned out when it was first powered up. And yes, it was wired in right, it was just a simple AC two speed motor.
Finally I started googling and saw that so many other people were having exactly the same problem. But Sears just kept buying crap from whoever the supplier was. Posts complaining about it went back many years.
One choice might be to find a different Xformer supplier, even a slightly different one as long as it can be mounted and the specs are equal or better.