continuous load for heat pump w/ heat strips

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mtnelect said:
It was installed by the homeowner after the house was purchased in 1965 without a permit.

See attachments that explains when and how Title 24 was established in California.
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Installed in 1965 or just sometime between 1965 and now? OEM/OEM equivalent replacement motor might be available but complete unit probably no longer the same today if it is that old.

Do they actually make you replace such a motor with more efficient one if all you are doing is replacing the motor? And if so how do they even know you replaced the motor if you don't apply for permit/inspection? Other than if you happen to be caught while in the act? One thing to discover something was installed without permit particularly when it comes time to sell the place, but not so easy to catch the repair where you replaced a component with same component presuming the item was otherwise permitted/inspected when it was new.
 
kwired said:
Installed in 1965 or just sometime between 1965 and now? OEM/OEM equivalent replacement motor might be available but complete unit probably no longer the same today if it is that old.

Do they actually make you replace such a motor with more efficient one if all you are doing is replacing the motor? And if so how do they even know you replaced the motor if you don't apply for permit/inspection? Other than if you happen to be caught while in the act? One thing to discover something was installed without permit particularly when it comes time to sell the place, but not so easy to catch the repair where you replaced a component with same component presuming the item was otherwise permitted/inspected when it was new.
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The unit was built like a tank, not like the flimsy sheet metal ones on today's market. It wasn't a motor problem, the main shaft that the fan blade attaches to was damaged by a loose pulley, which was beyond repair.

You are correct, today's real estate laws require you to reveal all construction work and defects on the property, which includes copies of all permits pulled or not pulled.

At this point in time, it's up to the customer on how to proceed. For me and the state, a permit will be pulled either way, and the replacement will meet Title 24.
 
mtnelect said:
The unit was built like a tank, not like the flimsy sheet metal ones on today's market. It wasn't a motor problem, the main shaft that the fan blade attaches to was damaged by a loose pulley, which was beyond repair.

You are correct, today's real estate laws require you to reveal all construction work and defects on the property, which includes copies of all permits pulled or not pulled.

At this point in time, it's up to the customer on how to proceed. For me and the state, a permit will be pulled either way, and the replacement will meet Title 24.
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I've repaired similar damages on belt driven wall fans with new shaft, bearings, etc. probably for less than replacing the entire unit. Definitely don't need to modify or adjust building framing/finishes to do so. They are usually basic pillow block bearings that you can get at Grainger or other industrial supply places. Might need good friends and or regular clients with a machine shop to cut keyways into new shafts if making you own out of blank stock.
 
mtnelect said:
In California we don't use the "Rule of Thumb" anymore. You can't take a 2,000 square foot home and divide 400 square feet to determine the size of unit. No more guessing, you have to do a "Heat Load" engineering study, like my attachment.

How can you determine the feeder size if you don't know what size unit you need ?
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The electrical engineer (which the OP is) would not be sizing an ac unit anyways. Sounds like he asking about a unit that has already been sized or will be sized by a mechanical engineer.
 
augie47 said:
Without entertaining the reasoning you might note Art 424 and 430 both require branch circuits to be considered continuous loads so your air handler and condenser are in line.
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That never made sense to me on HVAC equipment. If your HVAC is running 3 hours straight you have larger issues.
 
Knightryder12 said:
That never made sense to me on HVAC equipment. If your HVAC is running 3 hours straight you have larger issues.
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Not so sure. It could be hotter than the design temperature which will have the AC running for a long time. Can also happen if you turn the system off and the building bakes and then you want to cool it down. It may have to run continuously to pull it down if it needs to move it over 5 degrees and it is still hot outside. Same with setting back the heat on a very cold day and it needs to come up over 10 degrees. Many HVAC system are oversized.

Is running for over 3 hours normal operations? Probably not, so perhaps technically it should not be a continuous load.
 
If the unit is oversized, it does not run long enough to remove the latent heat; it feels like a swamp. If it is undersized, it runs all the time, and you end up with a high electrical bill.
 
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