AC condenser undersized - HI said nothing - to blame?

[Tim Spargo]

Some opinions please.

An agent at an inspection the other day tells me the plight of a family member of hers...

Bought a home, 80's construction. Alum. Dual Pane Windows. 2 story nearly 3200 sf, with basement, which isn now finished. Originally unfinished basement.

Not sure of Furnace size, but, the Condensing Coil was sized at 2 tons

She asks me what I think as she advised her family member to get 3 estimates, notify the HI of the oversight and "discuss". From what I gathered of the conversation, it sounded like estimates were obtained and this was headed to small claims. This is in an area that is regularly getting in the high 90's on a daily basis and the upper floor is not cooling below the low 80's

Anyway, my response was that:
HI's don't generally determine sizing of units, but it's fairly obvious that 2 tons is undersized for this structure. We advise if the unit is "functioning", not properly sized.

I also asked if the structure had additions. "Yes, the basement was converted" BINGO!

I indicated that although I felt on one hand that an experienced HI would notice that the unit was very undersized, I would have also inquired if this converted basement was permitted, as the space is likely to have threw off whatever calcs were originally thought of.

To me, this one is sooo undersized, I would have commented on it. But, do we say something about a 2 ton unit on a 1500 sf house... 2000 sf house? I mean, GEESH a 2 ton unit on a home over 3000 sf, in a hot area?

You get my picture.

I would think that if this one ends up in Small Claims, the HI gets fried there, unless he had something indicating a need for a 3rd party to come look at the AC unit by COE. I was told there wasn't, but haven't seen the report.

[David A. Andersen]

Is the system zoned?

Where is the house?

Not sure of Furnace size, but, the Condensing Coil was sized at 2 tons

Are we sure about this?

How is the duct designed?

Where is it located?

Did they add the basement to this system?

How many and where are the returns?

How many and where are the supply registers.

Where is the thermostat?

What is the duct Air Leakage Rate?

What is the Duct Insulation rating?

What is the construction of the duct?

Where are the TAB duct dampers located? What dampers?!

Is the Barometric Damper properly adjusted?

What is the negative static return air duct pressure.

What is the friction loss design pressure of the duct design?

What is the CFM capacity of the furnace?

How much Insulation in the attic, walls and under the basement floor? What is the R-Value of each?

What is the U-Value of the windows?

What is the orientation of the house?

Is it shaded? To what extent?

How many ACH/hr does the house have?

What is the CFM of ventilation (mechanical)?

What is the normal building static pressures?

Where is the Neutral Plane?

Where in the house are they uncomfortable, what season?

Just a few questions then, I can take a stab at a "wild *** guess" from here!

And Lastly, why does she think a Home Inspector has ANYTHING to do with ANY of this?!

[Brian E. Kelly]

Originally Posted by tspargo

Some opinions please.

An agent at an inspection the other day tells me the plight of a family member of hers...

Bought a home, 80's construction. Alum. Dual Pane Windows. 2 story nearly 3200 sf, with basement, which isn now finished. Originally unfinished basement.

Not sure of Furnace size, but, the Condensing Coil was sized at 2 tons

She asks me what I think as she advised her family member to get 3 estimates, notify the HI of the oversight and "discuss". From what I gathered of the conversation, it sounded like estimates were obtained and this was headed to small claims. This is in an area that is regularly getting in the high 90's on a daily basis and the upper floor is not cooling below the low 80's

Anyway, my response was that:
HI's don't generally determine sizing of units, but it's fairly obvious that 2 tons is undersized for this structure. We advise if the unit is "functioning", not properly sized.

I also asked if the structure had additions. "Yes, the basement was converted" BINGO!

I indicated that although I felt on one hand that an experienced HI would notice that the unit was very undersized, I would have also inquired if this converted basement was permitted, as the space is likely to have threw off whatever calcs were originally thought of.

To me, this one is sooo undersized, I would have commented on it. But, do we say something about a 2 ton unit on a 1500 sf house... 2000 sf house? I mean, GEESH a 2 ton unit on a home over 3000 sf, in a hot area?

You get my picture.

I would think that if this one ends up in Small Claims, the HI gets fried there, unless he had something indicating a need for a 3rd party to come look at the AC unit by COE. I was told there wasn't, but haven't seen the report.

Once it gets to court the HI lost....

Hard spot to be in, technically I would say the HI is not liable for the undersized AC..................

[Bob Elliott]

Home Inspectors do not calculate heat,electric or A/C systems.

[Tim Spargo]

Originally Posted by dandersen

Is the system zoned?

Where is the house? Southern UT

Are we sure about this? Size? Yes

How is the duct designed? Unknown

Where is it located? Main Floor in Garage

Did they add the basement to this system? YEP!!! after the fact

How many and where are the returns? Air Handler is main/middle floor, return likely there, which is poorly placed anyway. But I'm ASSuming too much

What is the CFM capacity of the furnace? Unknown to me

What is the U-Value of the windows? Unsure, but they're aluminum... not great I'm sure


Where in the house are they uncomfortable, what season? Second floor is uncomfortably HOT... 80+ deg...

Just a few questions then, I can take a stab at a "wild *** guess" from here!

And Lastly, why does she think a Home Inspector has ANYTHING to do with ANY of this?!

<---- Scary, I agree. My thought too. But David, are there realistically any scenarios where a 2 ton AC would be sufficiently sized in a region that gets hot like that?

The other parts I did delete, I wasn't really told any more than that. But I realize that there are a lot of variable that you are pointing out!


BK... I agree there too! From the sound of it, he's already lost!

[Tim Spargo]

Originally Posted by belliott

Home Inspectors do not calculate heat,electric or A/C systems.

I agree.

But, I posted this as the 2 ton size of the condensing coil vs a 3200 sf house in a hot area...

Just puttin' in out there for thought.

[James H. Bushart]

If the inspector has a pre-inspection agreement describing the SOP he will use signed by him and the client, has no advertising promising to "exceed" the SOP, and inspected/reported in accordance with the SOP....he has not problem, whatsoever.

[mnahrgang]

Originally Posted by tspargo

I agree.

But, I posted this as the 2 ton size of the condensing coil vs a 3200 sf house in a hot area...

Just puttin' in out there for thought.

Why are you "puttin' it out there" at all? It's beyond the SOP period.

Yes, we all exceed the SOP at various times for various reasons, but "missing" something that is outside the SOP should be the NORM.

[Tim Spargo]

Good Points, as I've said, I agree with our "duties".

[James H. Bushart]

The SOP is the SOP.

The reason home inspections run close to $400 instead of $4,000 is because they are quick (three-hour) non-invasive and unscientific observations. It doesn't really matter who you are...less than a complete Manual J calculation for sizing the unit and ductwork is a guess. Calling out an undersized unit as a material defect is outside the scope of a home inspection.

I think you were wrong to tell the client that it was "obvious enough" for the HI to call out.

[Tim Spargo]

Wrong? Maybe, maybe not? I can assure you that I let it be known that an inspection is not to determine the size/adequacy of appliances like this.

After all, this was at a HI I was performing, I had a vested interest in explaining such things.

But, just as I would comment about a 30 gal water heater in a 5 bedroom 3.5 bath home, if I noticed that a 2 ton unit was serving a 3200sf home, I'd probably make mention of it, especially if there were alterations/additions to the property. Do I have to? Nope.

[Joe Farsetta]

In most states, the sole person LEGALLY qualified to calculate the size of an HVAC system is a PE.

This is far beyond the scope of a home inspection. Providing the HI colored between the lines, he should be okay.

David Anderson provides an excellent range of questions that are considered when evaluating the needs of a dwelling and sizing the HVAC properly. While he may have the wherewithall to comment intelligently, a majority of inspectors simply do not.

I can almost guarantee that what David rattled off the top of his head were things not learned in any HI class...

[Tim Spargo]

Originally Posted by jfarsetta

In most states, the sole person LEGALLY qualified to calculate the size of an HVAC system is a PE.

This is far beyond the scope of a home inspection. Providing the HI colored between the lines, he should be okay.

David Anderson provides an excellent range of questions that are considered when evaluating the needs of a dwelling and sizing the HVAC properly. While he may have the wherewithall to comment intelligently, a majority of inspectors simply do not.

I can almost guarantee that what David rattled off the top of his head were things not learned in any HI class...

Good point Joe.. David's list may and parts of this post may be a good reply some day...

[David Garton]

Originally Posted by tspargo

Wrong? Maybe, maybe not? I can assure you that I let it be known that an inspection is not to determine the size/adequacy of appliances like this.

After all, this was at a HI I was performing, I had a vested interest in explaining such things.

But, just as I would comment about a 30 gal water heater in a 5 bedroom 3.5 bath home, if I noticed that a 2 ton unit was serving a 3200sf home, I'd probably make mention of it, especially if there were alterations/additions to the property. Do I have to? Nope.

I would probably do the same thing Tim but that's just my opinion

[Mark Thorman]

Originally Posted by tspargo

Wrong? Maybe, maybe not? I can assure you that I let it be known that an inspection is not to determine the size/adequacy of appliances like this.

How many inspectors include the size of a system in the report.

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