Why it matters
The H15GR-15 is a small 120 W inline pump with a flow switch that starts it when water runs. KolerFlo rates it at up to 1.5 bar (21.7 psi) of pressure, 396 GPH and 49.2 ft of head, with 1/2 in NPT brass fittings.
It's aimed at water heaters, solar heaters and single fixtures that lack pressure, rather than a whole house.
Who it's for, and who should skip it
Good fit if
- Water heater lines
- Solar water heaters
- Single fixtures
Look elsewhere if
- Whole-house boosting
- High-flow homes
Pros and cons
Pros
- Low price
- Automatic flow switch
- Compact
Cons
- Small boost
- Lesser-known brand
- Short warranty terms
Limitations to weigh
- Install a booster after the meter or pressure tank, with isolation valves; some water utilities restrict boosting on the main, so check local rules.
Specifications
Every figure below comes from the source shown in brackets. Where the maker doesn't state something, we say so instead of estimating.
| Material | Brass | Retailer |
|---|---|---|
| Dimensions (seller) | 6.9"L x 3.94"W x 3.6"H | Retailer |
| Max flow (maker) | 6.6 GPM | Retailer |
| Max head / lift (maker) | 49.2 ft | Retailer |
| Voltage | 110 V | Retailer |
| Horsepower | 1/6 HP | Retailer |
| Model number | H15GR-15 | Retailer |
Alternatives worth comparing
More booster & recirculation pumps we cover
Final verdict
A cheap fix for one weak line.
Where to buy
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Questions buyers ask
How much pressure does it add?
Up to 1.5 bar (21.7 psi), per KolerFlo.
What size connection?
1/2 in NPT.