Thermostatic Radiator Valve Repair & Replacement London
TRV stuck open, stuck closed, leaking, or just not responding? We repair and replace thermostatic radiator valves across London, same day. Standard TRVs, angled, straight, and smart TRVs — all brands.
Diagnose Your TRV Problem
Most TRV faults fall into four categories. Find your symptom below — it includes a quick DIY check you can do before calling us, and the likely repair cost.
Radiator always full heat — TRV makes no difference
Cause: Valve pin stuck open (corroded in down position)
DIY check: Remove TRV head. Wiggle pin with pliers — if it moves, lubricate and refit. If stuck solid, call us.
Fix & cost: Pin free: new TRV head (£65). Pin stuck: full valve replacement (£110)
Radiator cold — TRV at max but no heat
Cause: Pin stuck closed, failed TRV head, or lockshield closed
DIY check: Remove TRV head — if radiator heats immediately, the head has failed. Check lockshield (other end of rad) is open.
Fix & cost: TRV head replacement (£65) or full valve (£110) if pin stuck
TRV leaking from body or connection
Cause: Loose gland nut, failed olive, or cracked valve body
DIY check: Try tightening the gland nut (the nut just below the TRV head) with a spanner. If still leaking, call us.
Fix & cost: Gland tighten (£45) or full valve replacement (£110–£140)
TRV makes clicking/ticking noise
Cause: Wax capsule expanding and contracting rapidly — room temperature hovering at the set point
DIY check: Adjust the TRV setting slightly up or down. Clicking is normal but excessive clicking suggests the set point needs adjusting.
Fix & cost: Usually no repair needed — adjust setting. If persistent: TRV head replacement (£65)
How a TRV Works — and Why They Fail in London
A TRV head contains a wax or liquid-filled capsule that expands with heat and contracts when cool. As the room warms, it pushes a pin down into the valve body, restricting flow. As the room cools, the pin rises and hot water flows again.
| Failure Mode | Why It Happens | London Specific Factor |
|---|---|---|
| Pin corrosion (stuck open/closed) | Iron oxide (rust) from system water locks the pin | London's slightly acidic water accelerates corrosion without inhibitor |
| Wax capsule failure | Capsule degrades after 10–15 years | High usage in winter months wears capsules faster |
| Limescale on valve seat | Hard water deposits build on seating surfaces | London water at 280–320 mg/l — worst case in England |
| O-ring / gland seal failure | Age and thermal cycling degrade seals | Radiators in older London homes cycle more often with draughty windows |
| Smart valve battery drain | Smart TRVs run on batteries | Cold draughts near radiators exhaust batteries faster |
TRV Repair & Replacement Prices — London 2026
| Job | Time | Price (parts + labour) |
|---|---|---|
| TRV head-only replacement (standard M30×1.5) | 20–30 min | £65 |
| TRV head replacement (non-standard thread) | 30–45 min | £75 |
| Full TRV body + head replacement | 45–60 min | £110–£140 |
| Smart TRV installation — Tado, Hive, Drayton Wiser (per valve) | 20–30 min | £85 |
| Smart TRV hub setup + first valve | 60–90 min | £150 |
| Lockshield valve replacement | 45–60 min | £95–£120 |
| TRV leak repair (gland or olive) | 30–45 min | £45–£95 |
No call-out fee. Fixed quote before we start. 7 days a week including Bank Holidays.
Smart TRV Installation — Room-by-Room Heating Control
Smart TRVs let you set individual schedules for every room via an app. They learn your habits, respond to your location, and can cut heating bills by 15–30%. We install and configure all major systems:
| Brand | Boiler compatibility | Voice control | Standout feature |
|---|---|---|---|
| Tado | All major boilers | Google, Alexa, Apple Home | Auto geofencing — heats before you arrive |
| Honeywell Evohome | All major boilers | Alexa | Most precise zone control — 12 zones |
| Drayton Wiser | Most combi boilers | Google, Alexa | Best value smart TRV system |
| Hive Active Heating | Most boilers | Google, Alexa, Apple Home | Easiest to install and use |
TRV Repairs Across All London Boroughs
Same-day TRV repair available across London. We carry the most common TRV heads (M30×1.5, RA, M28) and smart TRV kits on the van.
TRV FAQs
How much does TRV replacement cost in London?
TRV head replacement (the plastic top part with the numbered dial) costs £65–£75 including parts — the valve body stays in place. Full TRV replacement (body and head, requires draining the radiator) costs £110–£140. Smart TRV installation is £85–£120 per valve. All prices include labour.
Why is my radiator stuck on full heat even when the TRV is closed?
A radiator that stays hot regardless of the TRV setting usually has a stuck-open valve pin. The TRV head contains a wax capsule that expands/contracts with room temperature to push a pin in the valve body. If the pin corrodes in the open position, the radiator runs at full output. You can sometimes fix this by removing the TRV head and manually wiggling the pin with pliers. If it won't move, the valve body needs replacing.
Why is my radiator cold even with the TRV turned to maximum?
If the radiator is cold with the TRV fully open, either the pin is stuck closed, the TRV head has failed and isn't releasing the pin, or the lockshield valve on the other end has been closed. Remove the TRV head — if the pin springs up and the radiator heats, you need a new TRV head. If the pin is stuck down, you need the full valve body replaced.
Can I replace a TRV head myself?
TRV head replacement is DIY-friendly if you buy the right size. Most UK TRVs use M30×1.5 thread, but some older valves use different thread sizes. Measure or bring the old head to the merchant. No draining needed for head-only replacement. If you're replacing the full valve body, the radiator must be drained first — call us if unsure.
Are smart TRVs worth it in a London flat or house?
Smart TRVs give room-by-room scheduling and can reduce heating bills by 15–30% by only heating rooms you're using. In a London flat with zone-controlled heating they're particularly effective. Payback is typically 1–2 heating seasons. We install all major brands and can integrate with Google Home, Alexa, and Apple HomeKit.
My TRV is leaking — is it urgent?
A leaking TRV should be fixed promptly. Turn the TRV to 0 (closed) and place a towel underneath. We can usually stop a TRV leak the same day — it's either a loose gland nut or a failed olive/seal requiring valve replacement.
Related Heating Services
TRV Problem? Fixed Same Day.
From £65 · No call-out fee · All London · Smart TRV installation available
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