LESLIE: Sherry in Georgia is on the line with question about determining electrical service size for her home. What can we do for you?
SHERRY: I’m interested in knowing when should I look out to upgrade an electrical panel. A central heating and air unit was installed but this is an older house. And I was wondering if there’s anything I need to look out for as far as voltage or whatever.
TOM: Do you know what size your service is right now, Sherry?
SHERRY: No. But they did mention it. Before the install, they did mention that that would need to be replaced but they never replaced it.
TOM: That would be a different contractor. Well, here’s the thing – is your house heated by gas?
TOM: The only appliance in your house that’s really going to be pulling a lot of power is going to be that central air-conditioning compressor. And I don’t know if you have an electric range or an electric dryer but you’d be surprised that most people would think you need a much bigger service than you actually need. If you had a 100-amp service, that would probably be big enough.
But I can’t really tell you specifically how to go about determining electrical service size because I don’t know what you have and you’re not aware of what you have. I think that maybe that’s a question that you could raise with an electrician but you don’t need a 200-amp service when you only have one air-conditioning compressor. A 16-amp even service itself, if it’s wired correctly, might be big enough.
Now, if this system was installed properly, which by that I mean has the right size breakers or fuses on the compressor itself and every other wire that’s in that panel then – and you’re not having any issues, you’re not blowing circuits right and left, you’re probably OK. But I would want to find that out from an electrician to go about determining electrical service size, not just the HVAC contractor that was trying to sell you the system.