why are my fuses blowing?

[kd5pck]

Yes, that a pretty vague question. I know that it could be many of things.

Came home yesterday and the outside unit just made a clicking noise when I adjusted the thermostat. Didn't sound right. I checked the fuses in the disconnect box with a multimeter and yep, they were blown. So I headed to Wally World since that was the only place open. got the replacement fuses and installed them. Set the thermostat to heat, adjusted the temp. and heard the same clicking noise. Checked the new fuses, and yes, they blew immediately. gonna be a cold night again tonight.

Anyone have any ideas on what I should expect to hear from my tech when I get him out? Is there something in particular that I should ask him to check while he is out?

Some background. I have a Goodman heat pump, unknown tonage or SEER rating. All I really know is that it's about 13 years old and needs to be put out to pasture. Lately I have been noticing some ice forming on the outside of the unit. When I do see ice, it seems like all I get is cold air blowing. I was turning the system off for 30-45 minutes and then turning it back on. Seemed to heat after doing that.

Any thoughts?

[kenney t]

sounds like a dead short to ground some where.

[tlb]

are they screw in or cartridge fuses?

[Twilly]

Twilly says you will most likely hear.......Sir do you have a major credit card?

[kd5pck]

They are 30 amp cartridge fuses.

I think that major credit card is going to end up being majorly maxed out soon.

[tlb]

more than likely you have a short in the outdoor unit but you can check your fuse holder make sure fuses are fitting tightly also check slots where holder plugs in and make sure not burnt.also use time delay fuses they will hold a little better.also small chance compressor is getting hard to start and a start capacitor will fix

[dijit]

Twilly says you will most likely hear.......Sir do you have a major credit card?

I agree with twilly

[Roadhouse]

Compressor is gone, I think.

[kd5pck]

things didn't look crispy in the disconnect box when I changed the fuses last night. I'm curious as to why I am hearing a clicking noise when I adjust the thermostat though. I heard this even though the fuses were blown. Weird. I am going to try to check things out a little more when I can to see if it's an obvious electrical problem with the electrical service and not within the unit's electrical system. If that makes any sense...

[kd5pck]

If the compressor is bad, would it make that clicking noise and also blow the fuses?

[tlb]

more than likely you are hearing the contactor clicking even if the fuses to the outdoor unit are blown the points on the contactor will still pull down because the transformer for the 24v is fed from the indoor unit

[kd5pck]

OK, that makes sense. I suppose I will head to the Depot tonight to get another set of fuses then try it again. Maybe a better inspection will find an obvious problem with the electrical service. My luck it's the compressor though.

[dijit]

OK, that makes sense. I suppose I will head to the Depot tonight to get another set of fuses then try it again.

I wouldn't bother. Do you have emergency heat?

[bmathews]

OK, that makes sense. I suppose I will head to the Depot tonight to get another set of fuses then try it again. Maybe a better inspection will find an obvious problem with the electrical service. My luck it's the compressor though.

This is the definition of insanity. Trying the same thing over and over again hoping for different results. Save yourself some $$$, possible damage to yourself and house and call a pro out tomorrow to investigate. Skip the depot, head back to wally world and buy yourself an electric blanket.

[tominos]

This is the definition of insanity. Trying the same thing over and over again hoping for different results. Save yourself some $$$, possible damage to yourself and house and call a pro out tomorrow to investigate. Skip the depot, head back to wally world and buy yourself an electric blanket.

lol i agree with this. if its blowing fuses everytime you put new fuses in, the problem is not the fuse.

[machery]

One quick question......do the fuses say "one time fuse"? if so, they will usually blow on a compressor start up surge, especially a cold start up. I would bet walmart does not sell a time delay or "FRN" type.

[Roadhouse]

If the compressor is bad, would it make that clicking noise and also blow the fuses?

Yes. The sequence is the low voltage is pulling in the contactor, thus the clicking, to allow the high voltage that is sitting there in wait on one side of the contactor to be able to pass through said contactor, to thus turn on said compressor which in turn is grounded and blowing the only protective path for high voltage electricity back to your electrical service panel, your fuses.


You might get lucky and a high voltage wire burned off or loose and is touching somewhere and your compressor MAY still be good. Either way, that electricity is "backfeeding" so to speak and your fuses WILL continually blow. Change them a thousand times and you will have the same result.

[dijit]

And don't go putting any pieces of metal in the fuse slots either.

[kd5pck]

Ha! Little pieces of metal in the fuse holders! I never claimed to be the smartest person, but I'm not that dumb either. I'm not insane either. Or do insane people realize they are insane or...
Anyway, the plan was to get more fuses and check out the disconnect box for anything obvious, like a loose wire or loose contact. I wasn't ready to put another set of $10 fuses in just to watch them blow again. I figured I would have them on hand for whenever I could get the repair tech out. I need them anyway. But that plan went out the window since I couldn't make it out to the Depot before they closed.
To answer the other question about the type of fuses, they are time delay fuses. I was surprised Wally World had one pair in stock.
Emergency heat?? What's that? (insert sarcasm). It's been running all the time set to emergency heat. It won't get above 60 degrees. It wouldn't be bad if it were the middle of August, 60 would be nice.
Powerball drawing is tomorrow night, maybe I will win and won't have to worry about this crappy heat pump anymore.

[beenthere]

As said by others. Don't put anymore fuses in. Have it checked by a tech. putting more fuses in, can do more harm to the system, and cost you more money to have it repaired.

[keeplearnin]

Remember no DIY you could get seriously maimed or electrocuted, I know you are a fix it man but sometimes yougotta pay so call the technician nowwwwwwwwwww.

[hvacart]

Sometimes its time to call it a day. A good tech can explain the trouble shooting problem to you as well as keeping you safe. The problem you are dealing with is on the load side of the contactor. You have to kill the power and using a meter check the wiring of the compressor and or fan side. Looking for a short to ground or phase to phase. A good tech will track the short to its source. Just because the fuses are blowing doen't mean all is lost but you have to know what you're doing.

Artie h.

[REP]

You already have gotten way more information than you need to get into real trouble.
The only thuing I would say is make sure you have a double set iof fuses on hand as the tech you call might not have the ones you need because most places now use non fused (breaker style) protection.

[kd5pck]

Well I just got back to work after meeting with the service tech. He told me that my compressor is bad and between that and the capacitor being blown, that was the cause of my fuses blowing. He told me that the cost of replacing the compressor, capicitor and the defrost board ( that was bad too) that I was looking at a cost close to the cost of replaciing the outside unit. Although no price was given. I asked hime how he would go about giving me a price on a new system. His response, " I could go take a look at what you have in the attic real quick and work you up a price in a few minutes".

Really? I suppose he was going to give me a price on a system identical to what I would be replacing. How do I know that this system was originally sized correctly? I told him fine, take a look and fax me a quote. I needed to get back to work anyway. I think I will be calling around to find someone else to give my hard earned money to.

[REP]

IDK,I think I would get a second opinion.Too many problems all at once,Why?
A bad cap makes sense but did he disconnect the wiring to the compressor and take a meter reading of it in order to claim a bad compressor?If it is a bad compressor ,you would have to have the whole system cleaned inside of the acid thats there.If he can get one of those r22 condensers you would need two filter dryers installed ,did he quote that.If he can't get one of those condensers then you will need to replace the indoor unit too.
Way too many questiobns here for my taste.

[blownfuse99]

That does seem like alot wrong all at once. I would also get a second opinion...And get prices from both companies....

[kd5pck]

I'm going to start shopping around for a contractor to install a whole new unit. Definitely not going to use this guy if he can give me a price in a few minutes. This tells me he is looking to just replace what I have with something the same size/specs without seeing if I need something different.

[keeplearnin]

Well iv'e seen plenty of solid copper "fuses" in the past. It could be a broken comp. terminal also but you'll need you friendly neighborhood ac man to determine that.

[PineKap]

I have just read this entire thread and one of the things mentioned was that ice was buildilng up on the outside of the Condenser, This does show signs of a bad Defrost board. If the board was bad for a long time then this could of contributed to the compressor going out.
Make sure to call out some one who will do a full Load calculation, Also make sure they check all ducting, Insulation and Building leakage.

Good Luck.

Kappl