Danfoss AVQ (003H6726) — self-acting flow controller, PN 25, DN 25, for district heating and cooling systems. The AVQ is a self-acting flow controller for district heating and cooling systems. It holds the flow rate constant and closes when the set maximum flow is exceeded. It has a control valve with an adjustable flow restrictor and an actuator with one control diaphragm; the valve and actuator are delivered assembled with the impulse tube fitted. Flow range 0.2–4.5 m³/h; flow-restrictor differential pressure 0.2 bar; Kvs 8 m³/h. Maximum differential-pressure range 20 bar; media temperature 2–150 °C; cavitation factor z ≥ 0.6; seat leakage 0.02 % Kvs (IEC 60534). Valve body Red bronze CuSn5ZnPb (Rg5); valve cone Dezincing free brass CuZn36Pb2As; seat Stainless steel, mat. No. 1.4571; control diaphragm EPDM. Connection External thread G 1 1/4 A (ISO 228/1), via tailpieces. Mounting version Free. Permissible media: District heating/cooling circulation water (Glycolic water up to 30%), pH 7–10. OEM P/N 003H6726. EAN 5702421542477. Technical data quoted verbatim from store.danfoss.com (code 003H6726) and the Danfoss AVQ data sheet.
| Code number | 003H6726 |
| Type | AVQ |
| Product group | Pressure and flow controllers |
| Function | Self-acting flow controller (closes when set max. flow is exceeded) |
| Valve size | DN 25 |
| Pressure class | PN 25 |
| Connection | External thread G 1 1/4 A (ISO 228/1), via tailpieces |
| Kvs value | 8 m³/h |
| Flow rate range | 0.2 - 4.5 m³/h |
| Flow restrictor differential pressure (Δpb) | 0.2 bar |
| Max. differential pressure range | 20 bar |
| Media temperature | 2 - 150 °C |
| Media pH | 7 - 10 |
| Cavitation factor z | ≥ 0.6 |
| Seat leakage rate | 0.02 % Kvs (IEC 60534) |
| Mounting version | Free |
| Stem position | Normally open |
| Permissible media | District heating/cooling circulation water (Glycolic water up to 30%) |
| Valve body material | Red bronze CuSn5ZnPb (Rg5) |
| Valve cone material | Dezincing free brass CuZn36Pb2As |
| Valve seat material | Stainless steel, mat. No. 1.4571 |
| Actuator diaphragm | EPDM |
| EU RoHS compliance | Yes with exemptions (6(c)) |
| REACH Candidate List substance | Lead (CAS no. 7439-92-1) |
| China RoHS | Out of scope |
| Net weight | 3.054 kg |
| Gross weight | 3.054 kg |
| EAN | 5702421542477 |
| Material | Valve body Red bronze CuSn5ZnPb (Rg5); valve cone Dezincing free brass CuZn36Pb2As; valve seat Stainless steel, mat. No. 1.4571; control diaphragm EPDM |
| Pressure rating | PN 25 (max. differential-pressure range 20 bar) |
| Temperature range | 2 to 150 °C (district heating/cooling water) |
| MOQ | 1 |
Danfoss AVQ for DN 25 district-heating/cooling flow control at PN 25. Set the maximum flow within 0.2–4.5 m³/h using the adjustable flow restrictor (Kvs 8 m³/h). Confirm the connection (External thread G 1 1/4 A (ISO 228/1), via tailpieces) and pressure class (PN 25) match the pipework; order the matching tailpiece/union-nut set separately. Maximum differential-pressure range 20 bar, media temperature up to 150 °C.