Question for electrically minded people

[Jersey mike]

So yesterday I had to service my a/c compressor, clean the coils.

The compressor has its own fuse box right near it as is typical and is original to when we bought the house 30+ years ago and the house built in the mid '60's. About 25 years ago I had a new furnace and a/c installed and the compressor (a second furnace and compressor has since been installed as well) moved to a different location and the original fuse box was used.

So back to the fuse box, when I opened the box the fuse has a small handle on it which is meant to pull out but because of its age and my ability to break things I just shut the power off at the main panel.

My question is do fuses go obsolete or out of use/service?  I'm wondering about this now because of its age and the longevity of its lifespan.

While inspecting the compressor I also noticed the metal flexible conduit leading from the fuse box to the a/c unit has some signs of cracks in the joints that make it flexible so I'll need to have an electrician service that so I'll ask them about the fuse but I'm wondering what I may be in store for if the whole fuse box would need to be upgraded or updated because it's wrapped by the vinyl siding we had installed many years later.

Appreciate any thoughts.

[scooperhsd]

That's really more of an HVAC question, and I can't give you a good answer. BUT - cracks in the line are not a good thing. That last "fuse" is really a disconnect,  and I think talking to a pro is your safest, best way to go. Disconnects are still used on 240V outside appliances (air conditioners, spas, pools).

[RP#62]

In our neck of the woods, that box by the AC is not a fuse box, its a disconnect.  Its required by code and is there so you can kill power to the unit when you are servicing it.  When you pull that handle out, you'll see there's a copper strip attached that bridges two terminals.

RP

[GiG]

Mike:
  A fuse will not fail "because of its age and the longevity of its lifespan". It is simply a short, a section of wire that will open if it sees excessive current.
If someone were troubleshooting and told you the problem was "a bad fuse", they would be incorrect. The fuse opens to protect circuitry, that's why it's in place. They typically don't go bad from "age and the longevity of its lifespan".   

[Thunderbolt]

As others have said the thing in the box that has a flip up lid is a disconnect.  It is there to be able to service the unit outside without going inside.  It completes the path for your 240VAC to the compressor.  If you pull it out there will be no power from that point on toward the compressor.  You can either flip the part you pull out 180 degrees and plug it back which will make the downstream device inoperable or leave it out on top of the box while you work on or clean the coils etc. so you will see it and remember to reinsert it in the proper direction.

[Willow]

Maybe the failure was a blessing in disguise.  If that AC is really 30 years old you may want to just replace it.

Up to date AC units are so much more efficient than the older ones it will only take you a couple of ears savings to cover the cost and from then on it's just savings.

[Timbo1]

As others have said it's a disconnect.  Some disconnects are fused some are not and they come in different amperage specifications depending on the equipment being connected.  Last year we replaced our HVAC with a larger one and I purchased a 60 Amp non fused disconnect with a 6' whip similar to this one to replace an old fused disconnect.  Cost about $60 and I'd imagine if you needed an electrician to install it wouldn't be more than a few hundred dollars including parts. 

[Jersey mike]

Thanks for the feedback guys, it's appreciated. I was questioning what I called the breaker because of it looks to be all plastic and having never fiddled with one I didn't want to touch it and have it break or something stupid during the high temps we were having and being July 4th weekend.


Willow, I didn't have a failure, so I was good there.

I'm on my 2nd compressor since we bought the house. The last time we upgraded from a 2 1/2 ton unit to a 3 ton unit, so we're good there for now...it's about 11 years old.

Instead of pulling what everyone is calling a power disconnect and I referred to as a fuse I shut the power off at the main breaker box. I didn't pull the disconnect because I have the great ability to break things at the most inconvenient times.

I appreciate everyone taking the time to drop a response.