The Caleffi NA25510 is the HYDROFLUSH fill and flush cart, a portable, pre-assembled and leak-tested pumping station with a 1/2 HP 120 V pump delivering up to 55 psi, for filling, purging and flushing solar, geothermal and hydronic heating systems with water, glycol and cleaning fluids.
Product data compiled from Caleffi North America technical documentation. Last reviewed July 2026.
Key Features
1/2 HP Pump, 55 psi
A 120 V AC, 1/2 HP pump delivers up to 55 psi - the pressure needed to drive air out of a hydronic system during purge.
Fills Solar, Geo and Hydronic
Pre-assembled and factory leak-tested for filling and flushing solar thermal, geothermal and hydronic heating systems.
Built to Travel
Welded steel powder-coated chassis, 10 in rubber tires and back arm bars - climbs stairs and loads into a van or truck.
Polyethylene Tank, Stainless Filter
Chemical-tolerant polyethylene tank (medium to 140 F) with a stainless steel filter.
Water, Glycol and Cleaning Fluids
Rated for water, glycol solutions and hydronic cleaning/flush additives.
3/4 in GHT Connections
Standard garden-hose-thread connections pair with the Caleffi NA11338 3/4 in x 8 ft GHT hose.
Technical Data
| Function | Hydronic filling and flushing station |
| Pump | Grundfos CM1-3, 1/2 HP, 7.6 A @ 115 V AC; 1-15 gpm delivery; max 55 psi (125 ft head) |
| Cart frame | Welded steel chassis, powder-coated |
| Tank | Polyethylene; max medium temperature 140 F |
| Filter | Stainless steel |
| Tires | 10 in rubber |
| Connections | 3/4 in garden hose thread (GHT) |
| Medium | water, glycol solutions, flush additives |
Documentation
Technical brochureRelated Products
- Caleffi NA11338 3/4 in GHT transfer hose, 8 ft
- Caleffi NA570971 HYDROFILL resin, 2 bag bucket
- Caleffi NA570974 HYDROFILL resin, 4 bag bucket
- Caleffi NA573102 Replacement demineralizing filter
Frequently Asked Questions
What is the Caleffi NA25510 used for?
Filling, purging and flushing solar, geothermal and hydronic heating systems - initial glycol fills, cleaning flushes and commissioning, with enough pump pressure to drive out trapped air.
How powerful is the pump?
A 1/2 HP, 120 V AC pump producing up to 55 psi.
Can one person move it on a job site?
Yes - the welded steel cart rides on 10 in rubber tires with back arm bars, designed to climb stairs and load into a van or truck.
What fluids can it handle?
Water, glycol solutions and hydronic cleaning/flush fluids; the polyethylene tank is rated for medium temperatures to 140 F.
What hose does it use?
3/4 in garden-hose-thread (GHT) connections; the Caleffi NA11338 8 ft GHT hose is the matching accessory.
- Type:
- Fill & Flush Cart
- Series:
- HYDROFLUSH
