Ravenheat boiler repair across London
We repair Ravenheat boilers still in use. Ring us, day or night.
- Ravenheat CS and HE boilers repaired
- All our engineers are Gas Safe registered
Makes we repair
How does booking a Ravenheat repair work, and what does it cost?
Booking: ring us any time, day or night, or send your details and we ring you back. We'll ask what the boiler is doing, and its model and any code on the display if you can see them. You don't need to know what's wrong. Finding the fault is the engineer's job. Then we tell you when an engineer can come, anywhere in Greater London.
What it costs: a repair's price depends on the part it needs, how long the job takes and when it's done. Our rates are higher in the evening, overnight and at weekends. Once the engineer has found the fault, the rate for the repair is agreed in writing before any work starts.
What happens on a Ravenheat repair visit?
A repair visit has three stages.
1. Before anything is touched
The engineer covers the floor around the boiler and asks what you have seen and heard since you rang.
2. Finding the fault
The engineer tells you which part has failed, whether they have it with them or must order it, and how long the work should take. No work is done until you say yes.
3. The repair
The engineer fits the part and checks the boiler runs as it should before leaving. The repair is guaranteed for 12 months, covering the parts we fit, the labour and any return visit.
What goes wrong on Ravenheat boilers most often?
Low pressure, a boiler that won't light and overheating are the faults Ravenheat's own guides and pages come back to most:
- Losing pressure. Every Ravenheat user guide starts its safety checks with the pressure, and the older guides say a low reading may mean a leak.
- Not lighting. A lockout after the flame fails, 01E, 01 or a steady red light, is the fault every guide explains.
- Overheating. The older guides put it down to air in the boiler, or water not moving round the heating.
- A hot flue. Each condensing boiler's guide warns that it shuts down when its flue gases get too hot.
- A blocked condensate pipe. The WH 100 and WH 130's chart looks at the condensate drain first when the boiler locks out.
- Frost. A frozen heat exchanger has its own code, 25E, and the frost protection needs the gas and power left on.
- Sludge. Ravenheat's advice was to flush the heating when a boiler is fitted, to protect the pump. Ravenheat also advised having the inhibitor in the water looked at every year.
- A summer off. A boiler left off for months can seize, so Ravenheat advised running it briefly every few weeks.
Whichever it is, we'll ask what the boiler is doing when you ring. Ravenheat stopped trading in 2023, and we still repair its boilers.
Ravenheat fault codes and what they mean
Ravenheat boilers show a fault in one of three ways:
- Two figures and an E, such as 01E, on the CS, the HE and the WH80 and WH90.
- A number alone, such as 01, on the CSI 120, CSI 150, HE 42, WH 100 and WH 130.
- A red light on the older boilers with no display. The light is steady when the flame has failed, and flashes when the boiler has overheated.
The same fault carries a different number on each, so we'll ask for the model. Ravenheat's guides give one reset. If the code stays, leave the boiler off and ring us.
01ERavenheat 01E (01 on the boilers that show a number alone): the boiler couldn't light, and has locked out
What it means: 01E means the boiler tried to light, found no flame and locked out. Ravenheat's manual also calls it E1. A CS makes three tries before it shows the code. On a boiler that shows a number alone, the code is 01. On the older boilers with no display, a steady red light means the same.
Possible causes, as the manual lists them:
- the gas supply
- the overheat thermostat
- the gas valve
- the spark igniter
- the electrodes
On a WH 100 or WH 130, the chart looks at these, in order:
- a blocked condensate drain
- the gas valve
- the fan starting
- the ignition board and its leads
What you can do:
- Press Reset once. On a WH 100 or WH 130, hold it for 1 to 3 seconds.
- On a boiler with a red light, switch it off and on at its main switch.
- On an LS 80, press the flame-failure switch.
If the code comes back, ring us, and leave the boiler off.
08ERavenheat 08E (28 on the boilers that show a number alone): the water pressure is too low
What it means: 08E means the pressure in the heating system is too low, or has fallen to nothing. Ravenheat's older guides add that a low reading may mean a leak. On a CSI 120, CSI 150, WH 100 or WH 130, the code is 28. The code 28 can also point to the water flow or pressure switch, or water not moving round.
Possible causes, in the order of the WH 100 and WH 130's chart:
- the low pressure switch
- the pump
- the system's pressure
What you can do: on a CS or HE, press P to see the pressure on the display. A WH 100 or WH 130 has a gauge.
On a CS, HE or WH boiler below 1 bar, top up with the filling loop as the user guide shows:
- Fit its hose between the two taps.
- Open one tap fully.
- Open the other slowly while watching the pressure.
- Close both at 1.5 bar at most.
- Take the hose off.
On a CSI 85, HE 85, CSI 120 or LS 80, the guide says not to top up. Below 1 bar, leave the boiler off and ring us, as there may be a leak.
If the code comes back, or the pressure keeps falling, ring us.
12ERavenheat 12E: too many resets
What it means: 12E means the reset limit has been used up. A CS allows five resets in 15 minutes, then shows 12E. Resetting again and again doesn't clear the fault behind a lockout.
What you can do: leave the boiler off and ring us. We'll ask which code showed before 12E.
06E/09E/21E/29ERavenheat 06E, 09E, 21E and 29E (04 on the boilers that show a number alone): the boiler has overheated; 02E: the water isn't moving
What it means: 06E, 09E, 21E and 29E mean a sensor has read the water too hot:
- 06E in the heating
- 09E at the overheat sensor
- 21E in the water coming back to the boiler
- 29E in the hot water
On a boiler that shows a number alone, the overheat lockout is 04. On a boiler with no display, a flashing red light means the same. 02E means the pump isn't moving the water round.
Possible causes:
- Ravenheat's older guides put overheating down to air, or water not moving round the boiler or the heating.
- The WH 100 and WH 130's chart looks at the overheat thermostat.
- The CS chart's answer to a boiler that stops short of its temperature is clearing air from the system.
What you can do: reset the boiler once. On a boiler with a red light, switch it off and on at its main switch.
If it trips again, ring us. Ravenheat's guides say to leave the boiler off and call an engineer. Air in the boiler, the pump and the thermostat are an engineer's work.
22E/23ERavenheat 22E and 23E (30 and 31 on a WH 100 or WH 130): the flue is too hot, or its sensor has failed
What it means: 22E means the gases leaving through the flue are too hot, and 23E that the flue sensor or its wiring has failed. On a WH 100 or WH 130, they show as 30 and 31. On a CSI 120 or CSI 150, a flue overheat shows as 30, and 02 means a blocked flue. Ravenheat's user guides for its condensing boilers warn that the boiler shuts itself down when its flue gases pass their limit, to protect itself.
Possible causes, from the WH 100 and WH 130's chart:
- 31 points at the flue sensor
- 30 points at the way the boiler is running
What you can do: reset the boiler once at most.
25ERavenheat 25E: the main heat exchanger has frozen
What it means: 25E means the boiler's main heat exchanger has frozen. Ravenheat's frost protection works with the gas and power on, showing AF. The pump runs below 10°C and the burner fires below 5°C, so the guides say to leave both on in cold weather.
What you can do: nothing at the boiler, as Ravenheat's guides give no step for 25E.
MoreEvery other Ravenheat code, in one list
Ravenheat's fault-finding chart for the CS 80 and CS 90 (2015) lists every other E code below, the one full list that survives. The HE80 and HE98S, and the WH80 and WH90, show their codes the same way, with 08E for low pressure. Their full lists haven't survived, so we'll ask for the model too.
03EThe heating flow sensor has failed
Possible causes
A damaged flow sensor
04EThe hot water sensor has failed
Possible causes
A damaged hot water sensor
05EThe fan's speed signal is missing
Possible causes
No speed control signal coming from the fan
10EThe water pressure is too high
Possible causes
Too much pressure in the heating system
13EThe control software has an error
Possible causes
A software error
24EThe heating return sensor has failed
Possible causes
A damaged return sensor
26EThe control board has failed
Possible causes
A damaged control board
41EThe flow is more than 35°C hotter than the return, for 25 seconds
Possible causes
Not named in Ravenheat's chart
43EThe return is more than 40°C hotter than the flow, for 30 seconds
Possible causes
Not named in Ravenheat's chart
44EThe return is more than 10°C hotter than the flow, for 60 seconds
Possible causes
Not named in Ravenheat's chart
No codeThe boiler stops before it reaches its set temperature
Possible causes
Air in the system, which needs clearing
No code, hot waterWeak hot water, or none
Possible causes
A blocked filter, the flow detector and its magnet, the hot water sensor, or debris in the plate heat exchanger
CLOWThe display's backup is charging after a long power cut
Possible causes
Not a fault. It clears in a few minutes.
AFThe frost protection is running
Possible causes
Not a fault
The CSI 120, CSI 150, HE 42, WH 100 and WH 130: every other code
From the user guide for the CSI 120 and CSI 150, and the fault-finding chart in the WH 100 and WH 130's manual. Not every boiler shows every code. Codes 02 and 14 are the CSI's and the HE 42's, and 31 is the WH's.
02The flue is blocked (CSI 120, CSI 150 and HE 42)
Possible causes
A blocked flue
06The hot water sensor or its wiring has a fault
Possible causes
The sensor or its leads
12The heating sensor or its wiring has a fault
Possible causes
The sensor, or water not moving round
14A flame is sensed when there should be none (CSI 120, CSI 150 and HE 42)
Possible causes
Not named in the guide
17The fan or its wiring has a fault
Possible causes
The fan's supply, or the fan
No code (WH 100 and WH 130)The boiler stops before it reaches its set temperature
Possible causes
Air in the system, or the automatic air vent
Sources, read on 9 October 2026: Ravenheat's installation and servicing manuals for the CS 80 and CS 90 (2015) and the WH 100 and WH 130, and its user guides for the CSI 120 and CSI 150, the CSI 85, the HE 85 and the CSI Primary, in the Internet Archive's copies of Ravenheat's closed website.
The fault codes of every other make, explained code by code.
Which Ravenheat boiler do you have, and how does it show a fault?
Ravenheat, the Leeds boiler maker, stopped trading in 2023, so its boilers are no longer made. We still repair them across London.
Depending on its age, a Ravenheat shows a fault in one of three ways:
- two figures and an E
- a number alone
- a red light
The model is on the boiler's data badge, and we'll ask for it and the code when you ring.
Not every sign is a fault:
- AF on the display means the frost protection is running.
- After reaching its temperature, a CS, WH or CSI 120 waits about 10 minutes before firing the heating again. Hot water still comes straight away.
- A white plume from the flue on a cold day is water vapour. If it looks like smoke, ring us at once.
Sources: Companies House's records for Ravenheat Manufacturing Ltd, and Ravenheat's user guides, manuals, product pages and FAQs, in the Internet Archive's copies of its closed website.
Worth knowing
Ravenheat boilers are no longer made, and we still repair them. Ravenheat Manufacturing Ltd, the Leeds maker, was wound up in 2023 and dissolved in 2025, and its website has gone.
How do you reset a Ravenheat boiler?
Each Ravenheat range resets its own way, as its user guides show:
- CS80, CS90, HE80 and HE98S: press Reset on the panel when a code shows, and the boiler relights. A CS allows five resets in 15 minutes, then shows 12E.
- WH 100 and WH 130: press Reset for 1 to 3 seconds.
- CSI 120, CSI 150 and HE 42: press Reset.
- CSI 85, HE 85, CSI Primary and RSF 82, 84 and 100: switch the boiler off and on again at its main switch.
- LS 80: after a failed flame, press the flame-failure switch. After an overheat, take off the grey cap, press the red reset button and put the cap back.
- RSF 820/20: a pilot-light boiler, with no reset button. If its pilot light has gone out, ring us.
Reset once. If the code or the light comes back, leave the boiler off and ring us with the code, as Ravenheat's guides say.
The pressure: a CS, HE or WH boiler should read 1 to 1.5 bar. Below 1 bar, its user guide shows how to top up with the filling loop, to 1.5 bar at most.
A CSI 85, HE 85, CSI 120, LS 80 or RSF 82, 84 or 100 is different. Its guide says to leave the boiler off below 1 bar and have it refilled by an engineer, as there may be a leak.
Over the summer, Ravenheat advised running the boiler for 15 to 20 minutes every few weeks, so its parts don't seize. In cold weather, leave the gas and power on, so the frost protection can run.
A frozen condensate pipe can be thawed with warm, never boiling, water, where the pipe is at ground level and easy to reach. Then reset the boiler. When a boiler won't fire up, and frozen condensate pipes.
Is your Ravenheat boiler still under guarantee?
A Ravenheat guarantee has no maker to claim from now. Ravenheat Manufacturing Ltd, which gave the guarantees, was wound up in March 2023 and dissolved in July 2025. No company has been named as taking over its guarantees or its parts. Whatever guarantee it was sold with, a Ravenheat is now repaired by an independent Gas Safe registered engineer.
Ravenheat sold its spare parts through specialist merchants, and each manual lists its parts by number. Parts are found by the boiler's model and GC number, from its data badge, wherever they are still available. We'll ask for the model when you ring.
Ring us for a Ravenheat repair. We are an independent firm, with no connection with Ravenheat.
What does a Ravenheat boiler service cover?
Ravenheat asked for a service at least once a year by a Gas Safe registered engineer, and advised using the engineer who fitted the boiler. Its manual's service covers:
- the flue and its seals
- the gas pressure and rate
- a combustion check with an analyser
- every joint
- the heat exchanger, brushed with a soft brush and flushed through the condensate trap
- the trap's float, cleaned
- the electrodes, checked and set
The inhibitor in the heating water is checked every 12 months as well.
We service every Ravenheat model, and give you the rate on the call. What a boiler service includes, check by check.
15% off a new boiler, fitted
The 15% comes off the price of a new boiler installation. We quote from photos of your old boiler, or after a free survey visit. Now is the time to replace an old or discontinued boiler.
Terms: 15% off everything in the price we quote for a new boiler installation. That means the boiler, its flue and controls, and the fitting. The offer is for installations booked by 31 December 2026. One offer per home, and not with any other offer.
Do you cover my part of London?
Yes: we travel all over Greater London, day and night, to repair Ravenheat boilers in every borough, north and south of the Thames. Pick your side of the river to see the areas.
North of the river
Every borough north of the Thames: Barnet and Enfield at the top, Hillingdon in the west, Havering in the east, and central London in between.
South of the river
Every borough south of the Thames: Richmond and Kingston in the west, Bexley in the east, and down through Croydon to Sutton and Bromley.
The other makes we repair
Every main make, combi, system and regular. Pick yours for its common faults, its codes and how we repair it.
Questions about Ravenheat boilers
Do I need to know what's wrong with my Ravenheat boiler before I ring?
No. Ring and say what the boiler is doing, or what you can see or hear, and we'll ask the rest. Finding the fault is the engineer's job.
Do you charge more in the evening or at weekends?
Yes. Our rates are higher in the evening, overnight and at weekends.
Can you repair an older Ravenheat boiler?
Usually, yes. It depends on the boiler's condition and whether its parts are still made. We'll ask for the model when you ring.
Is my Ravenheat boiler worth repairing?
Often, yes. Age alone doesn't decide it. What decides it is the rate for the repair against a new boiler, and how often the boiler has failed. The engineer gives you the rate for the repair, and the choice is yours. When a new boiler makes more sense.
Do you fit Ravenheat's own parts?
Yes, the maker's own parts wherever they are available. Each repair is guaranteed for 12 months, covering the parts we fit, the labour and any return visit.
How much does a Ravenheat boiler repair cost?
The cost of a repair depends on the part, how long the job takes and when it's done. The rate is agreed in writing before the repair starts. How our rates work.
Is Ravenheat still in business?
Ravenheat is no longer in business. Ravenheat Manufacturing Ltd, the Leeds boiler maker, and its parent company were wound up in March 2023, in a solvent winding-up. Both were dissolved in July 2025, and Ravenheat's website has gone too. With no maker left, there is no Ravenheat helpline or guarantee to call on. Ravenheat boilers are no longer made, and we still repair them. We'll ask for the model when you ring.
Why does my Ravenheat boiler keep losing pressure?
A Ravenheat that keeps losing pressure may have a leak, Ravenheat's older user guides say. On a CS, HE or WH, top up to 1 to 1.5 bar as the user guide shows. On a CSI 85, HE 85 or CSI 120, leave it off. If the pressure keeps dropping, ring us.
Why is the red light on my Ravenheat boiler on?
The red light on a Ravenheat with no display, such as a CSI 85, HE 85 or CSI Primary, means it has locked out. A steady light means the flame has failed. A flashing light means the boiler has overheated, often from air or water not moving round, the guides say. Switch the boiler off and on at its main switch once. If the light comes back, leave it off and ring us.
Can you still get parts for a Ravenheat boiler?
Parts for a Ravenheat are found by the boiler's model and GC number, from its data badge, wherever they are still available. The part numbers in its manual are used too. Ravenheat sold its spares through specialist merchants, and no company has been named as taking over its parts. We'll ask for the model when you ring, and the engineer tells you about the part before any work starts.
Who made Ravenheat boilers?
Ravenheat Manufacturing Ltd, founded in Leeds in 1987, made Ravenheat boilers. By its own account, its production was at two sites in Verona, Italy. Its sister brand, The White Boiler Company, sold the WH boilers.
Don't know what has failed? You don't have to.Ring and say what you can see or hear. Finding the fault is our job.
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A real person answers and gives you the rate on the call. No work starts until you say yes, and repairs are guaranteed for 12 months: parts, labour and any return visit.
