DIYbanter - View Single Post - need to downgrade breaker (from 40amp to 15amp) for new hvac?

dpb

wrote:
Hello,
I recently had a home inspection in preparation for selling my house.
The inspector informed the buyer that I need to downgrade the circuit
breaker (from 40amp to 15amp) for new hvac? He said he sees this
problem a lot. My father, who does a lot of DIY including some
electrical, says that if we change to 15amp when the hvac switches to
aux. heat it will blow the breaker?

I need to find out if this really needs to be changed, the inspector
warned the hvac unit could be damaged if this isn't changed. But I
don't want to have the change done if it will cause problems when the
unit goes to aux heat.

I'd call the hvac installer, but, clearly, they didn't think it was
necessary to change the breaker & I'd really like an independent
opinion on this.

ALSO, is changing a breaker best left to an electrician or might this
be something we could do ourselves?

I have a feeling the inspector doesn't have a clue, but...

Is this a new HVAC installation? Is this an existing breaker w/ a new
unit or a new installation for it? Either way, if the unit has been
recently installed, I'd first just check w/ the installers and find out
what they say before anything else. If it is a new installation, you
may well have some information for the unit that describes the required
service feed(s) -- check for that.

As someone else noted, if the service feed to the unit is sized properly
for the existing wiring, it's unlikely the breaker needs to be changed.
The point of breakers in distribution panels is to protect the wiring,
_not_ the device. The unit itself will be protected by internal fusing
or breakers or a combination of both. Thinking a breaker must match a
nameplate load rating for "protection" of the load device is a common
misconception I've found more than one inspector to have (hence my first
comment).

If you don't get a satisfactory response from the HVAC guys or from what
you can learn from the information left w/ the unit (again, assuming
it's new), then if you don't have sufficient expertise to determine for
sure it's time to ask an electrician out to check. I'd think it
unlikely to need that much, but you may have to go that route if the
inspection report has actually gone to the potential buyer to have
sufficient pedigree to satisfy...

Methinks this will turn out to be a tempest in a teapot...

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