240V Air Con vs 120V house

[David.Solar]

Hi guys, I am new to this forum.

My grandma's house is an old house that runs 120V.
Recently she had an AC installer come out to install two AC units.
The AC units run on 240V. Doh!
How do I get the AC units to work? I've got varying responses from different people.

The AC Installer said: the line coming from the the utility line is 120V, get LADWP to come out to change the line to 240V and we should be good.
DWP rep said: need to upgrade the service panel + change the line
Friend who's not an electrician said: just need to upgrade the outlets that the AC units plug into to 240V

I don't know what to believe...

Pls help!

Thanks for reading and I hope I can help out in the future with any Solar PV questions as I am in the Solar industry.

 

[Dennis Alwon]

You need to get a service change. You must call an electrician as you probably don't have the ampacity needed either

 

[iwire]

You need to get a service change. You must call an electrician as you probably don't have the ampacity needed either

Exactly.

 

[drspec]

if what you are saying is true, then the HVAC company that sold them the equipment is scum.

they should have made sure the existing service was large enough and compatible with the equipment they are selling.

 

[mike7330]

This is like buying the cart before the horse? Get your check book out!

 

[iwire]

if what you are saying is true, then the HVAC company that sold them the equipment is scum.

they should have made sure the existing service was large enough and compatible with the equipment they are selling.

I think that is a bit harsh.

If the unit is 15 - 30 amps I don't think they would be expected to check the service size.

And as far as the service being 120 .... come on, you know that is ancient and should have been upgraded long ago.

 

[infinity]

You need to get a service change. You must call an electrician as you probably don't have the ampacity needed either

Agreed, based on the bad advice and particular questions asked a professional electrician is needed.

 

[drspec]

I think that is a bit harsh.

If the unit is 15 - 30 amps I don't think they would be expected to check the service size.

And as far as the service being 120 .... come on, you know that is ancient and should have been upgraded long ago.

why is that harsh? every professional hvac company I have ever worked with always made sure the service was sufficient before selling a homeowner equipment.

The homeowner should have known that they would need a service change and upgrade before buying the equipment and imo the hvac company should have been professional enough to inform them of that.

 

[infinity]

Maybe the AC installer just put in some window units.

 

[ceb58]

Maybe the AC installer just put in some window units.

That were bought at Slowes or Home Despot with professional installation :slaphead:

 

[kwired]

why is that harsh? every professional hvac company I have ever worked with always made sure the service was sufficient before selling a homeowner equipment.

The homeowner should have known that they would need a service change and upgrade before buying the equipment and imo the hvac company should have been professional enough to inform them of that.

Why do you think HVAC guys are going to know if the service can handle this?

Some are better with electrical knowledge than others, but at same time it sounds like these are smaller units that probably will not need major electrical upgrades in 95%+ cases. HVAC guy maybe never even realized there is no 240 volts available.

Existing 120 service possibly doesn't have the capacity needed even if you had the same sized units in 120 volt versions.

 

[drspec]

Why do you think HVAC guys are going to know if the service can handle this?

Some are better with electrical knowledge than others, but at same time it sounds like these are smaller units that probably will not need major electrical upgrades in 95%+ cases. HVAC guy maybe never even realized there is no 240 volts available.

Existing 120 service possibly doesn't have the capacity needed even if you had the same sized units in 120 volt versions.

if they were plug in window units, why would they assume there were receptacles close enough to plug into?

if they were central air units where none previously existed, why would they assume anything?

 

[kwired]

if they were plug in window units, why would they assume there were receptacles close enough to plug into?

if they were central air units where none previously existed, why would they assume anything?

I didn't mean that no branch circuits wouldn't possibly need to be run. But adding a couple 15 amp or less window A/C units usually doesn't require additional service capacity.

 

[drspec]

I didn't mean that no branch circuits wouldn't possibly need to be run. But adding a couple 15 amp or less window A/C units usually doesn't require additional service capacity.

and don't you think they should have let the homeowner know that an electrician would probably need to get involved?

that way they could have known if the purchase of the ac units along with the needed electrical work was within their budget

 

[kwired]

and don't you think they should have let the homeowner know that an electrician would probably need to get involved?

that way they could have known if the purchase of the ac units along with the needed electrical work was within their budget

That would be nice, but I don't expect it to happen either, I have encountered much worse incidents of someone like HVAC guys installing something and then owner finds out they need to make some fairly significant changes to be able to power it.

How about something like what happened in this thread?

 

[iwire]

why is that harsh?

I told you why.

I know plenty of electricians who would think nothing of assuming a 15-30 amp 240 volt circuit could be added to a home without an up grade.

 

[PetrosA]

Maybe this is regional, but here in SE PA I wouldn't ever expect to find a 120V service still in use in a house. I guess it could happen, but I haven't seen one since the 1980s. For it to happen the service would have to be over 50 years old at least and I would only even suspect it if I saw fuses in the house rather than breakers. But again, haven't seen them in a long, long time...

 

[kwired]

Maybe this is regional, but here in SE PA I wouldn't ever expect to find a 120V service still in use in a house. I guess it could happen, but I haven't seen one since the 1980s. For it to happen the service would have to be over 50 years old at least and I would only even suspect it if I saw fuses in the house rather than breakers. But again, haven't seen them in a long, long time...

I think what you described is almost exactly what you will find if you run into a house with a 120 volt only service almost anywhere.

 

[PetrosA]

I think what you described is almost exactly what you will find if you run into a house with a 120 volt only service almost anywhere.

What I meant was that maybe there are parts of the country where 120V services are still somewhat widespread. This area isn't one of them.

 

[cowboyjwc]

While it may be true that the house is only fed with 120v there may still be 240 availible. What I ususally see is that a triplex is run but one of the wires is capped off. The reason is that usually the utility wire will go bad before the service does.

Now that's not to take away from the fact that your old A-base meter will still need to be changed.

And while I agree that the AC guys might have seen a 100 amp service and thought nothing of it and, of course, just assumed that there was 240V availible. I still think that the owners should have some recourse. This is about a $4000 mistake, give or take. If it was made at my house I would have to worthless AC units sitting there.