Honeywell transformer problem

[drkwoods]

I have the honeywell AT140A1042 24v transformer running two auber PIDs to open and close my furnace valves for the propane banjo burners. In the middle of brewing the whole system blew the main fuse in my control panel. I opened it up and smelled excess heat and the transformer was very very and smoking. It's only about 30 brews in. I'm looking for ideas on how or why it blew? Is one transformer not enough for two gas valves? Too much load? Common failure? I just want some ideas before I simply replace the transformer. I want to prevent this from happening. Any advice is gladly accepted!

 

[jcav]

Sorry to hear your transformer blew. A lot of people use the 75VA 24 VAC transformers to run the two valves without fear of overloading them. Here is a link...

http://www.simplyplumbing.com/honeywell-at175a1008.html

Just a suggestion though. I hope it works out for you, I've seen your build thread and your videos and you got an awesome rig!

Good Luck,

John

 

[kladue]

The 40VA transformer you used is not meant to operate more than 1 valve at a time, you need the 75VA version (AT175A1008) for 2 valves operating at same time. With the controllers switching on and off at different times you have managed to keep the overload below smoke and flame threshold for a while by minimal overlap of on times. Sounds like you must have needed both burners for more than a couple minutes, and the continuous overload finished off the 40VA transformer with usual release of magic smoke.

 

[drkwoods]

ok great. I just bought a 100VA version. This should be what I need then. Thanks guys! the one I got does look very similar Jcav! and thanx for the Props! Cheers

http://www.auctiva.com/hostedimages...689722525&images=689722525&formats=0&format=0

if you notice any problem with this one let me know. Im running two burners and its also sending 24v to a relay for my float switch (usually only during sparge and minimal burner use)

 

[drkwoods]

The 40VA transformer you used is not meant to operate more than 1 valve at a time, you need the 75VA version (AT175A1008) for 2 valves operating at same time. With the controllers switching on and off at different times you have managed to keep the overload below smoke and flame threshold for a while by minimal overlap of on times. Sounds like you must have needed both burners for more than a couple minutes, and the continuous overload finished off the 40VA transformer with usual release of magic smoke.

LOL yea I saw the genie leave the "building"
Thanx for the advice

 

[The10mmKid]

Amazing how they pack the Genie and smoke in during manufacturing.

'da Kid

 

[drkwoods]

amazing how they pack the genie and smoke in during manufacturing. 'da kid

lmao!!

 

[drkwoods]

Ok transformer is here but it's got two black wires (primary's I'm sure) and two yellows, one has a white stripe.. The old transformer had two output terminals. One was R (load) and the other was C. How do I correlate those to this new transformer?

 

[day_trippr]

You can wire the primary side (black wires) and secondary side (yellow wires) anyway you want, unless you care about phasing (and for most applications this is a don't care). The wires are keyed for phase-sensitive applications.

There's a helpful pdf for this transformer here...

Cheers!

 

[drkwoods]

Wow that's easy. Thanxx a mil. We r up and runnin already.