Do Natural Gas Furnaces Need Yearly Maintenance?

[blackhat]

If the breaker is larger than that listed as max on the equipment rating plate, that is a code violation  Manufacturer specs are there for a reason.

[fixtureman]

If the breaker is larger than that listed as max on the equipment rating plate, that is a code violation  Manufacturer specs are there for a reason.

Isn't that what a fused disconnect is for.  I thought that the amps listed on the equipment is so you don't under rate the wiring and breakers

[Snipe Hunter]

If the wiring is capable of 40 amps what is the beef about the breaker.  They a install 30 amp disconnect at the compressor.  What you are saying would be like you can't plug a 15 amp coffee pot into a 20 amp circuit.  The breaker is there to protect the wiring not the appliance.

Right, as far as the wiring goes but not the load. A coffee pot is not on a dedicated circuit if it were a hard wired, commercial coffee maker, it would need to be installerd per the manufacturer's rcommendation. Most of the newer condenser disconnects I see are simply disconnects and not fused. The manufacturer wants the installer to protect the unit, they don't care about the conductor. It's not about protecting the wiring it's about protecting the unit itself and installing it per the manufacture's recommendations. The label on the units all have max circuit protection amps printed on them. A coffee maker is 30 bucks and it's not a fixed appliance. A condenser/compressor unit is 5 grand. The warranties all state "void if not installed per manufacturer recommendations". Over fused is not per manufacturer recommendations. Make the breaker trip, not the unit fail. If I don't call it out, I'm not doing my job. If it does fail with an over fused circuit and the warranty claim is denied... they're coming after me. There's only a few component circuits in a home that a home inspector is required to check for wire size and breaker rating. Kitchen countertop receptacle wire size and breakers, dedicated microwave circuit and the condenser circuit. So I do it.

[Roly]

Right, as far as the wiring goes but not the load. A coffee pot is not on a dedicated circuit if it were a hard wired, commercial coffee maker, it would need to be installerd per the manufacturer's rcommendation. Most of the newer condenser disconnects I see are simply disconnects and not fused. The manufacturer wants the installer to protect the unit, they don't care about the conductor. It's not about protecting the wiring it's about protecting the unit itself and installing it per the manufacture's recommendations. The label on the units all have max circuit protection amps printed on them. A coffee maker is 30 bucks and it's not a fixed appliance. A condenser/compressor unit is 5 grand. The warranties all state "void if not installed per manufacturer recommendations". Over fused is not per manufacturer recommendations. Make the breaker trip, not the unit fail. If I don't call it out, I'm not doing my job. If it does fail with an over fused circuit and the warranty claim is denied... they're coming after me.  There's only a few component circuits in a home that a home inspector is required to check for wire size and breaker rating. Kitchen countertop receptacle wire size and breakers, dedicated microwave circuit and the condenser circuit. So I do it.

In my area when they replace a outdoor condensing unit they normally change the outside disconnect as my old one was solid blade.  They install a fuse able disconnect with the proper sized fuses to protect the unit.  The unit install was permitted and inspected.   
 There is no need to replace the breaker in the main panel or the wiring going outside to the new disconnect when the fuses are in the disconnect to protect the unit.   It would just add unnecessary costs.  
    Are you pulling the outside disconnect to check for fuses as they are mounted on the inside of the pullout ?    Roly

[fixtureman]

In my area when they replace a outdoor condensing unit they normally change the outside disconnect as my old one was solid blade.  They install a fuse able disconnect with the proper sized fuses to protect the unit.  The unit install was permitted and inspected.   
 There is no need to replace the breaker in the main panel or the wiring going outside to the new disconnect when the fuses are in the disconnect to protect the unit.   It would just add unnecessary costs.  
    Are you pulling the outside disconnect to check for fuses as they are mounted on the inside of the pullout ?    Roly

That is what they did with mine 3 weeks ago.  They said it was code here to have a fused disconnect with the proper fuses.  I had a fused disconnect that was the same as they installed only 22 years old so they replaced it.

[JosephP]

... The warranties all state "void if not installed per manufacturer recommendations". Over fused is not per manufacturer recommendations. Make the breaker trip, not the unit fail. If I don't call it out, I'm not doing my job. ...

That makes a lot of sense.  I thought you (et. al.) were saying it was a code thing which didn't make sense (but I'm no electrician!).  (Then again, a lot of code things don't make sense to me (or at least the cost:benefit doesn't make sense).)  But I see where the warranty piece comes in.

[blackhat]

I don’t like to get into code specifics as ours, while very similar, is not the same as whichever is in force somewhere else. Most, however have clauses equating to” Equipment shall be installed in accordance with the manufacturer’s instructions and this document”. All of course subject to AHJ interpretation. 

Not a fan of fused disconnects. Weatherproof versions are pricey and offer no real advantage. Fuses are susceptible to being replaced with oversized as a temporary fix for a problem someone can’t find or repair.

[atgcpaul]

What's a reasonable price for a furnace checkup?

[lincmercguy]

I didn't really do a lot of maintenance for mine. I checked and cleaned the filter often, to keep air movement up more than anything. I cleaned off the condenser coils a couple times each Summer as well. I took the covers off and checked for any kind of issues.

When I sold the house, I had it inspect and tested before listing. I was quite clear that I was not going to replace it as an inspection item just because it was older.

My Mom had the same furnace, same year, and had it replaced. I stole all of the good parts off of it, so I had plenty of deterrent parts to make sure nothing broke.

[fredhargis]

What's a reasonable price for a furnace checkup?

The outfit that installed my furnace/heat pump has a yearly "early bird" deal where they do a full checlup for a flat fee. So far that has been $100 plus any parts cost (filters, etc.) and they guy usually spend about 2 hours doing it. One finished I get a full page of items he checked and the result. I suspect that flat fee might be a little higher this year. It has to be scheduled by the end of this month (the early bird part) and I'll probably be calling them next week. That said, I'm sure it's a regional thing so the costs may vary widely, and frankly I don't even know iof what I'm paying is "reasonable"....but it seems fair enough to me.