T&T: A/C Pump Problems

[Larry N. Brown]

Dave's  post got me to thinking about my system. I have 2  Little Giant 
4MDSC pumps rated at 22 gpm @ 0 head for 4 16.5 K ac units. I figure I have 
about 3' head so I think I have around 15 gpm. The minimum according to 
Dave. I think Flagship Marine called for 500 gpm/unit.

I seem to remember that too high a flow rate could cause problems too. My 
units use 5/8" feed hoses. Does this sound about right?

Looking over the pump data sheet I noticed it needs oiling every 6 months. 
I've never oiled them. Anyone know how to do it?

Regards,

Larry and Teri
M/V Cigano, 47' Prairie Sundeck Cruiser
Lying: Slidell, LA
N 30 13.28
W 89 48.63






> Mike, that's a lot of plumbing and "head" for one centrifugal pump, IMHO.
>
> Several things:
> 1. Is the pump breaker popping or is it the AC high pressure cutout that 
> is
> shutting down the pump and compressor(s)? The Marine Air units do have a 
> HP
> cutout I hope!
> 2. Centrifugal pumps run with the inlet completely blocked without any
> increased load on the motor so blockage shouldn't be an issue with the 
> motor
> load.
<snip>