# Car vac (100W) vs Home Vac (1000W)...

1. May 19, 2015

### escape_velocity

A typical home vacuum cleaner has the following specs
Input watts (Electrical) = 1000W
Suction = 80 inch H2O
Output watts = 100 air watts

where as a 12V car vacuum cleaner has
Input watts (Electrical) = 100W
Suction = unspecified (10 inch guesswork)
output watts = unspecified (10 air watts guesswork)

car vac manufacturers don't publish output air watts or suction so lets say we guess it to the above figures.
The fact is even at such low suctions car vacs still do sell and people use them.

But what I don't understand is given that there is such a huge difference in specs how does a car vac even pull in dirt, is 10 inch of water capable to generate enough suction power, or are car vacs actually generating higher suctions than my initial guess which I don't see how they could given that the input power is so low?

2. May 19, 2015

### jerromyjon

The size of the inlet is a big factor for performance.

3. May 19, 2015

Staff Emeritus
Have you ever used a car vac? It demonstrably picks up dirt.

4. May 19, 2015

### Staff: Mentor

Since the application is smaller, the lower suction is less noticeable.

5. May 19, 2015

### escape_velocity

I guess you are saying that a car vac would have a smaller inlet than a home vac but I don't have any idea how that help's here?

6. May 20, 2015

### billy_joule

They could have the same flow velocity and suction if the nozzles are sized appropriately. Less power doesn't necessarily mean less suction.

7. May 21, 2015

### jerromyjon

I'm pretty sure Bernoulli's Principle applies but I don't know how to apply it with a vacuum,

8. May 21, 2015

### Staff: Mentor

I'm not quite sure I understand your issue, but could you just assume there is no such thing as a vacuum and apply it then?