The Caleffi 574207A is an AutoFill Combo with a 1/2 in press connection, pre-assembling an automatic filling valve with a testable ASSE 1013 RPZ backflow preventer to feed and protect a hydronic system in one code-compliant unit.
Product data compiled from Caleffi North America technical documentation. Last reviewed July 2026.
Key Features
Fill Valve + Testable RPZ
Pre-assembled 553-series AutoFill filling valve with a 574-series testable reduced-pressure-zone backflow preventer.
ASSE 1013 High-Hazard Rated
Meets high-hazard cross-connection requirements for boiler feed with chemical treatment or glycol.
Pre-Adjustable Fill Pressure
Set the target system fill pressure; the valve reduces and holds it automatically.
Lead-Free Construction
Suitable for connection to the potable water supply.
Technical Data
| Function | Combination automatic filling valve and backflow preventer |
| ASSE listing | ASSE 1013 |
| Certifications | ASSE 1013, CSA B64.4 (ICC-ES PMG-1433); NSF/ANSI 372 (ICC-ES PMG-1360) |
| Connection | 1/2 in press inlet x 1/2 in NPT female outlet |
| Adjustment pressure range | 3-60 psi |
| Factory pressure setting | 15 psi |
| Pressure indicator | Visual pre-adjustment indicator (no integral gauge), accuracy +/- 2 psi |
| Maximum operating pressure | 150 psi |
| Medium temperature range | 40-150 °F |
| Material | brass |
Documentation
Technical brochureRelated Products
- Caleffi 573002A 1/2 in ASSE 1012 Fill + Backflow Combo
- Caleffi 573006A 1/2 in ASSE 1012 Fill + Backflow Combo
- Caleffi 573007A 1/2 in ASSE 1012 Fill + Backflow Combo
- Caleffi 553542A 1/2 in Auto Fill Valve
Frequently Asked Questions
What is the Caleffi 574207A?
It is an AutoFill Combo: an automatic filling valve pre-assembled with a backflow preventer, feeding a hydronic system while protecting the potable supply.
Which backflow preventer is included?
A testable ASSE 1013 reduced-pressure-zone (RPZ) preventer, rated for high-hazard applications such as glycol or chemical treatment.
When do I need ASSE 1013 instead of ASSE 1012?
Most codes require an ASSE 1013 RPZ when the system contains glycol or chemical treatment (high hazard); ASSE 1012 covers typical low/intermediate-hazard residential boiler feed. Confirm with your local authority.
- Type:
- Filling Valve & Backflow Combo
- ASSE Standard:
- ASSE 1013
- Series:
- AutoFill Combo
- Connection Type:
- Press
- Connection Type:
- NPT Threaded
- Connection Size:
- 1/2 in
