Commercial Valves & Controls London

Motorised valve replacement — 2 port and 3 port

A 2 port zone valve opens a circuit and proves it with a microswitch that fires the boiler; a 3 port mid-position valve diverts between heating and hot water. When the synchronous motor burns out, the microswitch sticks or the paddle jams, the result is heating with no hot water, hot water with no heating, or a system that heats when nothing is calling. Most valves allow the actuator head to be changed without draining the system, which keeps the repair quick and clean.

• 2 port zone valve replacement
• 3 port mid-position valve faults and replacement
• Actuator heads changed without draining where possible
• Microswitch faults causing boiler to fire or not fire

PICVs, commissioning and differential pressure valves

Pressure independent control valves hold a set flow rate regardless of pressure changes elsewhere, which is why they are standard on modern commercial and communal systems. When they are wrongly set, blocked with debris or fitted the wrong way round, circuits starve and the system looks unbalanced. We replace and set PICVs, change commissioning sets and record readings, and replace differential pressure control valves that are failing to hold the pressure across a riser or index circuit.

• PICV replacement, setting and flow verification
• Commissioning valve replacement and recorded readings
• Differential pressure control valve replacement
• Strainers cleaned to protect new valves

Pressure reducing valves and PRV repair

Pressure reducing valves protect fittings, cylinders and appliances from high incoming mains pressure. A failed PRV either lets full pressure through — noisy pipework, dripping outlets and discharging expansion relief — or over-throttles and leaves the building short of flow. We test the pressure before and after, service or replace the cartridge where the body is sound, and replace the valve where the seat has eroded, then set the downstream pressure to suit the equipment it protects.

• Pressure reducing valve replacement and cartridge service
• Downstream pressure set to the equipment specification
• Relief valves discharging due to PRV failure
• Water hammer traced to failed pressure control

Solenoid valves and automatic air vents

Solenoid valves on fill lines, gas interlocks and process supplies fail closed or fail to close, and both are urgent in a commercial kitchen or plant room. Automatic air vents are small but cause repeated problems: they weep and mark ceilings when the seat wears, or they seize shut and leave air in a circuit that then refuses to heat. We replace both with correctly rated components and isolate them properly so future replacement does not need the system drained.

Plant rooms, blocks and commercial sites

Valve work is rarely a single-component job in a plant room — a valve fails because a strainer is blocked, because the pump is running at the wrong duty, or because the circuit was never balanced. We look at the arrangement as a whole, replace what has failed, correct the settings around it and leave a record of the flow rates and pressures set. Sites on a maintenance contract get priority attendance when a valve fault takes out heating or hot water.