30 AMP SURGE GUARD

No test button?

all the lights were on when I disconnected it as the plugs showed heat burns

Surge Guard Instructions

When you plug in the 'Power On' lights should be lit. (top 2 or 3 depending on model)
Also bottom 'Surge' LED should be lit. If not ON then no surge protection

No typical life span.......but only 1 yr. warranty (limited)

Should NOT rattle. Unit is sealed and is NOT serviceable.

Contact Surge Guard if less than 1 yr old (good luck with that)
LINK

Removed because I did not assume that the OP was a Do-It-Yourselfer.
Randy

It IS serviceable. Had the same problem with mine. When I called them, no help as was out of warranted. Asked if I could take it apart, the reply was " it's yours, do what you want with it!". So I took the back off, yes you can with some work. Found 3 of the bolts had come loose holding the relay and were ratteling around in side. Took some locktite and reattached the bolts. Lots of silicon when putting case back together. Still works great. They really need to use locktite in production, this seems to be a common problem.

I have a test system but frankly I purchased it for other needs (Kind of expensive) but the unit performs multiple functions.. One is Spike supression and if it's more than 5 years old odds are that's not as good as it once was.. However you can easily add mnore spike supression.. (the devices providing are even easy to replace)

The other functions are power line monitoring and high/low voltage cutoff. If hte LCD display is showing the voltage and current. then the monitoring is likely working. To test current requires a variable AC voltage source.. I have a small one (Good enough for testing) but odds are if the display displays the proper voltage plus or minus one volt (Compare to meter) then it's working.