What is K BTU/HR versus BTU/HR for a cooling system mean?

[Bruce P.]

Hi,

So my friend's dad is building a ~600 sq ft ADU in southern California and on the drawings it says:

"Per Title 24, the BTU/HR rating for the equipment are:

Total water heater: 199.7K BTU/HR

Total heating equipment: 205K BTU/HR

Total Cooling System: 100.5K BTU/HR"  

When looking at air conditioning systems, I see them being sold as something like "4 tons, 48000 cooling BTU". 

What does the "K" in "100.5K BTU/HR" mean and how do I map that to "cooling BTU" when ordering a unit?

Thanks!

[Jim Goebel]

@Bruce P.

The K is for 1000.  In other words, 60 kBTU/hr = 60,000 BTU/hr.

That must be a huge house!  200kBtu/hr for the heating system, for instance - a decent say 2500 sq ft house in this climate (Des Moines IA) might take an 80 kBTU/hr or maybe an 100 kBTU/hr furnace.

I don't know much of anything about Title 24 but my guess is that those sizes are 'design' sizes.  Actual industry sizes, from my experience are more 'standard' and at least on the smaller units (ie: up to 100kBtu/hr) they go up in increments of 20,000 Btu/hr.  

Make any sense?

Jim