Fuses Blowing

[spatterson691]

The HydroFlash installed and worked just fine for over 6 months now. Then the fuse blew so I replaced it. It then worked just fine another month, then blew the fuse again. We have no overlapping stations in our watering schedule (and only 1 has 2 valves on it), so I don't think it's a valve overload. This last time we confirmed that it blew during a watering cycle and at which station it blew. If it happens again, we'll also check to see if it's the same one. What else could be causing this?

[Support]

The most common cause is a bad valve solenoid or shorted wiring.

HydroFLASH uses a time delay fuse so if is run at or near it's limit, over time it can blow.

The most likely cause is excessive current being drawn by one of your valves. A in-line AC current measurement with a meter would be the best way to diagnose a suspect valve. A standard valve usually draws about 250mA when ON. I would bet that the one that was on when you blew the fuse is bad.

Let us know if you need some extra fuses.

Hope this helps.

[spatterson691]

I measured one of the "good" valves and it drew 250mA, just as you estimated. I them measured the "suspect" valve and it drew 280mA. That seems like a small difference. Do you have a suggestion of a draw that is suspiciously high?

More fuses would be welcome. I have 1 left of the 4-pack that I bought at Radio Shack, but I'm not sure when the stores will shut down leaving me with mail-order as the only source.

[Support]

The measured difference is negligible so it looks like it is working in the normal range. I might be that you have an intermittent short. If the log shows that it keeps failing on the same valve, I would replace the solenoid or swap it out. The fuse you are using should be a time delay/slow-blow type (fuse element look like a spring vs a single thin wire). It should be a 1A fuse. We have been running up to three valves on at a time for years with HydroFLASH without fuse issues but when they do blow it indicates an issue with a valve or external wiring 99.9 percent of the time.

Contact support via email and we will send you out a few spares.

Hope this helps.

[spatterson691]

Thanks. The fuses I got from Radio Shack say slow-blow, but they have a straight wire element, not the spring-like element I usually see in slow blow fuses. I'll contact support off-line for fuses.

I looked at one of my valve boxes and noticed that 2 out of 4 (15 year old) solenoids have cracks in them, and one is showing rust thru the cracks. I also suspect it's an intermittent shorting solenoid and just ordered replacement solenoids for every valve. I suspect that replacing all the solenoids will solve the problem. Thanks for the help.