The ZL-4130 Ball Valve Set is a matched pair of 1" BSP full-bore isolation valves supplied in colour-coded red and blue to distinguish supply from return. Designed to connect directly to the 1" MT flat-sealing ports on standard UFH stainless steel manifolds, they provide a positive quarter-turn shut-off for isolating the manifold from the heat source — essential for system maintenance, pressure testing, and future servicing without draining the entire circuit.
1"
BSP Size
Full Bore
Ball Valve
Pair
Supplied
Red & Blue
Colour Coded
Brass
Construction
Compatibility Note: These valves are sized for the 1" MT connections on the ZL-117502–ZL-117512 stainless steel manifold range. Check thread type before ordering — red handle fits the supply (flow) port; blue handle fits the return port. If temperature monitoring at the manifold inlet/outlet is required, select the ZL-4012 set with integrated temperature gauges instead.
Installer Tip: Fit these ball valves before filling the system. Having isolation at the manifold means the manifold can be removed or serviced in future without draining the entire primary circuit — a requirement on any professional installation.
Quarter-Turn Full-Bore Isolation
A full-bore ball valve introduces negligible pressure drop when open, ensuring the manifold pump group receives full system head. The quarter-turn action gives a clear open/closed indication and positive shut-off — no partial seating, no drips.
Colour-Coded Red & Blue Handles
The red handle is fitted to the flow (supply) valve and the blue handle to the return — an industry-standard colour convention that eliminates installation errors and speeds up commissioning. Each handle is secured to prevent rotation on the stem.
Brass Construction
Valve bodies are manufactured from brass, providing excellent strength and corrosion resistance in closed heating circuits. Brass is the industry-standard material for hydronic system isolation valves and is compatible with all common system inhibitors.
Direct Manifold Compatibility
Supplied as a matched pair specifically dimensioned for the 1" supply and return connections on the ZL-series stainless steel manifold. Installation requires only a suitably-sized spanner — no adapters or additional fittings needed.
| Technical Specification — ZL-4130 |
| Part Number |
ZL-4130 |
| Description |
1" Ball Valve Set for Manifold — Blue & Red Handle (Pair) |
| Valve Size |
1" BSP |
| Valve Type |
Full-bore ball valve, quarter-turn |
| Body Material |
Brass |
| Handle Colours |
Red (flow/supply) & Blue (return) |
| Quantity |
Pair (2 valves) |
| Temperature Gauge |
Not included (see ZL-4012 for gauge version) |
| Application |
UFH manifold supply & return isolation |
| Compatible Manifolds |
ZL-117502 to ZL-117512 stainless steel manifold range |
Frequently Asked Questions
What is the difference between ZL-4130 and ZL-4012?
The ZL-4130 is a straightforward isolation ball valve pair with colour-coded handles — its sole function is on/off isolation of the manifold. The ZL-4012 adds a built-in temperature gauge to each valve, allowing the installer to read supply and return temperatures at the manifold without fitting separate temperature sensors. Choose ZL-4012 where temperature monitoring at the manifold is required.
Are these valves compatible with heat pump systems?
Yes. The brass valve bodies are compatible with closed heating circuits using all standard inhibitors, including those recommended for heat pump installations (e.g. Fernox HP5, Sentinel X100). Ensure the system is correctly inhibited to prevent corrosion throughout the circuit.
Do I need these if the manifold already has an end-set?
Yes. The end-set on the manifold body provides fill, drain, and flush connections for the circuit loops — it does not isolate the manifold from the primary heat source pipework. The ZL-4130 ball valves fit between the primary pipework and the 1" MT manifold inlet/outlet, allowing the manifold to be shut off independently of the boiler or heat pump circuit.
What tools are needed for installation?
A pipe wrench or adjustable spanner is sufficient to tighten the valve connections to the manifold ports. Apply PTFE tape or thread sealant to the male thread before assembly. Do not over-torque — finger-tight plus ¾ to 1 full turn with a spanner is adequate for a sound seal on a flat-face connection.
