12/24v roof top AC

[colinm]

Nah, the video is sponsored and concentrates on promotion rather than information. It reminds me of those stupid ceramic heater adverts on social media that claim to heat a room using little power because the unit is "super efficient" it's a load of crap.
10000btu ....you'd need 70mm cable to supply the 300A to the unit if that figure was genuine.
Using 12v battery power for heating a MH simply isn't on. Cooling is naturally less effective and efficient than heating so powering cooling from batteries in a MH will be even harder.
Ultimately the laws of physics prevent you from consuming little and getting a lot, you can't defy the laws of physics, it's impossible to get summat for nowt.
Will it cool? Yep.
How much? Not a lot.

Sorry I missed this post.
A/C units are heat pumps, they use the "laws of physics" to give a greater output than input.
If it had been a non-invertor heatpump I would expect it to draw 120amp, not had much experience of invertor heatpumps, but they are supposed to be more efficient, so the 66amp figure might not be to outrageous.

 

[merl]

Sorry I missed this post.
A/C units are heat pumps, they use the "laws of physics" to give a greater output than input.
If it had been a non-invertor heatpump I would expect it to draw 120amp, not had much experience of invertor heatpumps, but they are supposed to be more efficient, so the 66amp figure might not be to outrageous.

The inverter system replaces the old on-off thermostat type control with a better design whereby the motor speed goes faster or slower depending on demand, rather like modern boilers that modulate up and down rather than switching on and off. It's a tweak rather than a game changing improvement, around 10-15% supposedly.
I swapped out my old American Fridge freezer a couple of years back, some sellers claiming big energy savings from the inverter type, but the manufacturers annual consumption figures were similar to non inverter type.
So maybe 110A rather than 120A maybe?

 

[mistericeman]

The inverter system replaces the old on-off thermostat type control with a better design whereby the motor speed goes faster or slower depending on demand, rather like modern boilers that modulate up and down rather than switching on and off. It's a tweak rather than a game changing improvement, around 10-15% supposedly.
I swapped out my old American Fridge freezer a couple of years back, some sellers claiming big energy savings from the inverter type, but the manufacturers annual consumption figures were similar to non inverter type.
So maybe 110A rather than 120A maybe?

Heat pump AC (particularly inverter systems)

Are really pretty efficient.... Partly from the fact that they add 'waste' heat from the compressor to the heat they 'recover' from the ambient.....

 

[Thistle]

People often misunderstand the power requirement for cooling capacity in BTUs and see it as the same as heating btus where 3000 btu is around 1kw. In reality cooling btus are a lot lower.

This video is a rough rule of thumb to work it out, many of these Chinese units currently flooding the market come nowhere close to their claimed cooling output.

 

[Nesting Zombie]

See what I mean

Why ?….it’s like I’m a blinking magnet for them