The Evolve Contract 15mm Straight TRV (Thermostatic Radiator Valve) gives automatic, room-by-room temperature control for radiators fed by pipework that runs directly in line with the radiator connection. As part of the same Evolve Contract range as the angled TRV, it shares the same reliable thermostatic mechanism in a straight body suited to vertical pipe runs, floor-fed connections, and installations where the pipework already aligns with the valve.
A self-contained liquid expansion sensor head automatically adjusts flow into the radiator as room temperature changes, cutting unnecessary heating and reducing boiler running time. Finished in chrome and white, this straight TRV suits everyday domestic central heating installations, refurbishments and new-build projects alike.
15mm
Pipe Size
Straight
Valve Style
0-28°C
Temp Range
10 bar
Max Pressure
150 kg/h
Normal Flow
1 Year
Warranty
Good to Know
A straight-pattern valve is the right choice where pipework runs vertically up from the floor, or comes out of the wall in line with the radiator connection - if your pipework enters the radiator at an angle instead, the Evolve 15mm Angled TRV is the correct fit. This valve is bi-directional, suitable for flow or return installation within the stated pressure limits.
Straight 15mm Body
Suits pipework that runs directly in line with the radiator connection, such as floor-fed risers or in-wall vertical runs.
Thermostatic Control
Self-contained liquid expansion sensor head automatically adjusts flow as room temperature changes, without any wiring or power source.
Bi-Directional Design
Valve body is rated for use on flow or return pipework, giving installers flexibility on system layout.
Wide Temperature Range
Adjusts from 0°C to 28°C, including a frost protection setting at approximately 7°C to help protect the system in unoccupied rooms.
Chrome/White Finish
A clean, coordinated look that suits most radiators, valves and fittings found in UK domestic heating systems.
Standard UK Connection
15mm compression connection fits directly onto standard UK central heating pipework.
Product Details
Product type
Thermostatic Radiator Valve (TRV)
Valve style
Straight
Finish
Chrome / White
Manufacturer
BiWorld (Evolve Contract)
MPN
EV-C15S
Connections & Sizing
Pipe size
15mm
Connection
15mm x 1/2" compression (1/2" BSP)
Performance
Temperature range
0°C - 28°C, with frost protection at approx. 7°C
Normal flow rate
150 kg/h
Maximum flow rate
470 kg/h
Maximum working pressure
10 bar
Maximum pressure differential
1 bar
Maximum water temperature
100°C
Maximum ambient temperature
50°C
Flow direction
Bi-directional, suitable for reverse flow within manufacturer limits
Warranty
Manufacturer warranty
1 year (subject to manufacturer's terms)
How do I know if I need a straight or angled valve?
It comes down to how your pipework meets the radiator. If the pipe runs directly in line with the radiator connection - straight up from the floor, or straight out from the wall - a straight valve like this one is correct. If the pipe approaches from the side and needs to turn 90° into the radiator, choose the angled version instead.
Is this valve suitable for flow and return pipework?
Yes. The valve body is bi-directional, so it can be fitted on either the flow or return side of the radiator, with reverse-flow use permitted within the stated pressure limits.
Does it need batteries or a power supply?
No. It uses a self-contained liquid expansion sensor in the valve head, which expands and contracts with room temperature to open and close the valve mechanically - no power source is required.
Does this come with a lockshield valve?
No, this listing is for the straight TRV only. A separate lockshield valve is fitted to the opposite end of the radiator to balance the system and is sold separately.
Can I use this with a heat pump system?
This TRV can be used on heat pump systems, but because heat pumps run at lower flow temperatures than a gas boiler, actual heat output at the radiator will be lower than figures based on a standard boiler flow temperature. Always size radiators and valves against your system's actual low-temperature output data for heat pump installations.
BTU & WATT Calculator
Room Dimensions
Room Type
Living Room
Bedroom
Kitchen
Bathroom
Conservatory
Hallway
Glazing Type
Single Glazed
Double Glazed
Triple Glazed
External Walls
0 Wall
1 Wall
2 Walls
3 Walls
4 Walls
Insulation Level
Poor
Average
Good (New Build)
Required Heating
0
Watts
0
BTUs
Do you have a question about this product?
One of our expert advisors will be happy to help you!
