GRAT 1.5HP Cold Plunge Chiller
#1 in Over 1/2 HPFull review
The cheapest way here to a big cooling number, for large tubs in warm places.
Amazon $799$799
The GRAT 1.5HP Cold Plunge Chiller is the better cold plunge chiller overall, rated 3.6 to 3.4. The GRAT 1.5HP Cold Plunge Chiller leads on coldest and value. The Fox Plunge 1HP Cold Plunge Chiller costs $129.05 less ($669.95 vs $799).
Fox Plunge 1HP Cold Plunge Chiller
#2 in Over 1/2 HPFull review
A low-priced 1 HP chiller for a big tub, without the sanitizer or app of pricier units.
Amazon $669.95$669.95
Prices were last checked November 2, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the GRAT 1.5HP Cold Plunge Chiller for coldest (down to 36 °F vs down to 39 °F) and value ($533 per HP ($799, 1 1/2 HP) vs $670 per HP ($669.95, 1 HP)).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every over 1/2 HP cold plunge chiller; a clear win is highlighted. How we rank explains each one.
| Factor weight | GRAT 1.5HP Cold Plunge Chiller | Fox Plunge 1HP Cold Plunge Chiller |
|---|---|---|
| Overall rating | 3.6/5 | 3.4/5 |
| Value 30% | 97 $533 per HP ($799, 1 1/2 HP) | 88 $670 per HP ($669.95, 1 HP) |
| Coldest 15% | 100 down to 36 °F | 75 down to 39 °F |
| Sanitation 10% | 50 filter | 50 filter |
| Heating 10% | 50 heating not stated (neutral score used) | 50 heating not stated (neutral score used) |
| Noise 10% | 50 noise rating not published (neutral score used) | 75 50 dBA |
| Warranty 25% | 0 1-year warranty | 0 1-year warranty |
Specifications
| GRAT 1.5HP Cold Plunge Chiller | Fox Plunge 1HP Cold Plunge Chiller | |
|---|---|---|
| Cooling | ||
| Compressor | 1 1/2 HP | 1 HP |
| Cooling capacity | 10,500 Btu/h | - |
| Lowest temperature | 36 °F | 39 °F |
| Water and build | ||
| Filter | Yes | Yes |
| App or wifi | Yes | - |
| Voltage | - | 120 V |
| Noise | - | 50 dBA |
| Warranty | 1 year | 1 year |