Our verdict
Pick the M53 for the proven Zoeller design and full cast iron. Pick the CDU790 for a lower price, a vertical float that fits narrow pits and top suction that avoids air lock, with a three-year warranty.
The central trade-off
Switch. Float-operated M53; integrated vertical float on the CDU790, rated for 1 million cycles.
Intake. The CDU790 draws from the top, which keeps it clear of pit debris and needs no weep hole.
Build. All cast iron for the M53; epoxy-coated steel motor housing with a cast iron volute for the CDU790.
Side by side
| Specification | Zoeller M53 Mighty-Mate Sump Pump | Wayne CDU790 Sump Pump |
|---|---|---|
| Horsepower | 1/3 HP | 1/3 HP |
| Max flow (maker) | Not stated by the maker | 63 GPM |
| Max head (maker) | 19.25 ft | 20 ft |
| Switch | Not stated by the maker | Not stated by the maker |
| Housing | cast iron | Cast Iron |
| Discharge | Not stated by the maker | Not stated by the maker |
| Power cord | Not stated by the maker | Not stated by the maker |
| Weight | 21 lb | 16.4 lb |
| Warranty | Not stated by the maker | 3 Year Limited |
Values are the makers' published specifications. "Not stated" means the maker doesn't publish it.
Which should you choose?
Choose the Zoeller M53 Mighty-Mate Sump Pump if
- You want all cast iron
- You trust the classic design