Aqua-Flo pumps are extremely common in spas and hot tubs, and the range spans several distinct families built over many years. The seals are not shared across them, and one model has a production split that trips people up.
Find your family first
Dominator — and the 1995 split
Aqua-Flo changed the Dominator's seal. Pre-1995 units take one part; later units take another.
Aqua-Flo Dominator Pre-1995 shaft seal, 92500050
If you do not know your pump's age, look for a date code on the motor label before ordering. Getting this wrong is the most common Aqua-Flo mistake we see.
Flo-Master and Flo-Master FMHP
Aqua-Flo Flo-Master FMHP Series shaft seal, 92500150
A and B Series
Aqua-Flo A and B Series shaft seal, 92509040
Pond-Flo
The pond variant uses its own seal, 92500151.
Spa duty is hard on seals
Spa pumps run hotter than pool pumps and cycle far more often. Every start is the moment of maximum seal wear, before the fluid film establishes between the faces. A pump cycling several times a day ages its seal much faster than one running a single long cycle.
Add higher chemical concentration in a small water volume, and spa seals are genuinely consumable.
Symptoms worth acting on immediately
- Water under the equipment bay
- A whine or growl that changes with pump speed — the bearing is already taking water
- Rust staining below the motor
- Repeated GFCI trips — water is reaching the windings. Stop using the spa until it is fixed.
Fitting
Same rules as any carbon/ceramic seal, including the counter-intuitive one: lubricate the rubber, never the faces. See why mechanical shaft seals fail.
For Jacuzzi-branded spa pumps see our Jacuzzi shaft seal guide.
Before you reassemble
Seat every o-ring with a thin film of food-grade silicone. Dry rings pinch and take a set — the usual reason a new seal weeps within a season. Aqua Flex Food Grade Silicone Lubricant is what ships in our kits.
O-rings only. Never lubricate the polished faces of a mechanical shaft seal.
Beaver Island Parts Company is not affiliated with, endorsed by, or sponsored by any equipment manufacturer named on this page. All brand names, model numbers and part numbers are the property of their respective owners and are used solely to identify the equipment our replacement parts fit.