HERTFORDSHIRE, BEDFORDSHIRE & CAMBRIDGESHIRE
Boiler Repair in Harlow
Boiler repairs across Harlow, from the first new town homes to Church Langley and Newhall. Fixed £150 + VAT (£180 including VAT) diagnostic, with £70 off a same visit repair.
What goes wrong with Harlow boilers
No heat or no hot water
Often a pump, a diverter valve or the controls. In a combi, hot water that surges hot then cold usually points to scale on the plate heat exchanger, which is common in water this hard.
Pressure that keeps dropping
A weeping radiator valve, a relief valve letting by or an expansion vessel that has lost its charge. Each is found by testing, not guessing.
Lockouts and fault codes
The boiler has shut itself down on ignition, flame detection or overheating. A code that returns straight after a reset needs an engineer.
Kettling and frozen condensate
Kettling is water boiling in a heat exchanger narrowed by scale or sludge. A frozen condensate pipe stops the boiler after a hard frost, often with a gurgle and a code.
Get a fixed price before we start
Call and talk to an engineer, or send us the details and we will come back to you with a price.
Two water zones, both very hard
Affinity Water publishes two zone reports named after the town. In 2025, Harlow North (AF024) averaged 330 mg/l as calcium carbonate across 144 samples, ranging from 265 up to 438 mg/l. Harlow South (AF094) averaged 310 mg/l, from 265 to 350.
Both averages are above 300, which Affinity classes as very hard, and the width of the North range means hardness varies within the town itself. The reports do not say which neighbourhoods fall in which zone.
National guidance under the Building Regulations recommends treating water harder than 200 mg/l before it reaches a combi. Without that protection, scale gathers on the hottest surfaces, and a lot of the hot water faults we repair here start there.
Fault finding before any price
Resetting a boiler can get it going again, but it does not show why it stopped. Our engineers read the fault history, then test ignition, flame sensing, the fan, the pump, gas pressure and combustion until the failed part is found.
They also look at the heating water. Sludge from steel radiators blocks heat exchangers and wears out pumps, so if it is part of the problem, you are told, because a repair that ignores it may not last.
Only then do you get a price. If more than one thing is wrong, each is priced separately so you can decide what to do and when.
Heating in the older new town homes
Much of Harlow was built in the decades after 1947. In those homes we still meet small bore and microbore circuits, gravity hot water from a cylinder and, now and then, an original back boiler behind a fire.
Microbore pipe blocks easily when the system water is dirty, and a radiator cold at one end of a terrace can be a balancing issue or a stuck valve head rather than a boiler fault. We check both before blaming the boiler.
Where the old system and the boiler are both near the end of their lives, we tell you so, rather than fitting parts to something that will fail again.
Newer neighbourhoods
Church Langley was completed in 2005 and Newhall dates from the early 2000s, with Gilden Park more recent still. Boilers there are younger and faults tend to involve pressure, controls or an installation detail rather than wear.
If your boiler is still under a manufacturer’s guarantee, tell us when you ring. You may prefer to go to the manufacturer first, and we would rather you knew that before booking.
On these estates the boiler is often in a kitchen cupboard, a utility room or the loft. Tell us where yours is, as a loft boiler needs safe access and decent lighting before an engineer can work on it.
Renting from the council or a housing association
Almost 30% of Harlow homes are owned by the council or a housing association. If you rent one of them, the boiler is normally your landlord’s to repair, so report the fault to their repairs line first.
If you own your home, or you are a private landlord yourself, we can help directly, and the same fixed diagnostic price applies whichever part of the town you are in.
Diagnosed properly before anyone quotes
A fixed diagnostic price, all makes and models, and a straight answer on repair or replace.
What you can safely check
Before ringing, it is worth trying these:
Read the pressure gauge; most sealed systems sit around 1 to 1.5 bar cold
Check the power, the timer and the thermostat
Reset once, and note any fault code
In frost, pour warm water along the outside condensate pipe
Stop there. Taking off the casing or touching the gas valve, burner or flue is legally reserved for a Gas Safe registered engineer. Ours carry a Gas Safe ID card with their photo, and you are entitled to ask to see it.
What the diagnostic costs
Finding a boiler fault in Harlow costs a fixed £150 + VAT (£180 including VAT). That covers attending, diagnosing and any minor work needing no parts, with up to an hour on site. If you agree the repair on the same visit, £70 of it is deducted.
Out of hours gas work is £225 + VAT for the first hour and £75 + VAT for each half hour after, plus the £50 + VAT (£60 including VAT) call-out. All of it is confirmed on the phone before we set off.
Repair or replace
We repair all the common makes, not just the Vaillant, Ideal and Worcester Bosch we install. A sound boiler with one failed part is worth repairing, and that is what we will say.
An old back boiler, or a boiler with a badly scaled heat exchanger and repeated faults, may not be. Then you get the repair price and the cost of replacing it, from £2,375 + VAT (£2,850 including VAT), and our boiler installation in Harlow page explains the rest.
For most standard swaps in Harlow we can install the next day, subject to survey, and we take the old boiler away with us.
After the repair
The engineer tests the boiler on heating and hot water, explains what failed and tells you about anything else that is wearing. Nothing extra is done without your agreement.
Our labour is guaranteed for 12 months, and our engineers are our own employees, Gas Safe registered under 956889. If the boiler is due a service, it can be added on the visit for £50 + VAT (£60 including VAT); see boiler servicing in Harlow.
★★★★★
Rated 4.9 on Google by the people we work for
Why choose Vantage
Rated 4.9 on Google from more than 700 reviews across Google, Checkatrade and Trustatrader. Qualified, accredited engineers, a fixed price before any work begins and a labour guarantee on every job, from an established local company with an office team you can actually reach. No job too small.
Gas Safe registered
Company registration 956889. Every gas engineer carries their own Gas Safe ID card, and you can ask to see it.
Refcom F-Gas certified
REF1024550. Legally required for air conditioning installation and servicing, and we hold it.
CHAS Elite accredited
Veriforce CHAS assessed for health and safety, which is why commercial clients and landlords use us.
City & Guilds and BPEC qualified
Qualified, insured engineers on every job. No subcontracted strangers.
700+ reviews, 4.9 on Google
Across Google, Checkatrade and Trustatrader. Read them before you book.
Labour guarantee on every job
12 months on repairs, installations and everything else. Two years on a full bathroom refit. If anything we did develops a fault, we come back and put it right.
Fixed price before we start
The price is agreed with you before any work begins. No hidden extras on the invoice.
24/7, answered by a person
The emergency line is answered every day of the year by someone who can send an engineer, not a call centre.
Fully stocked vans
Five vans carrying the parts that fail most often, so most jobs are fixed on the first visit.
An office team behind every job
An established local business with multiple engineers and a dedicated office team to keep you informed.
Vaillant myREWARDS and Ideal Max accredited
Accredited installer status means extended manufacturer warranties on the boilers we fit.
Emergency response within the hour
Our average response to an emergency call is under an hour across Hertfordshire, Bedfordshire and Cambridgeshire.
Trusted & Accredited Professionals
Frequently asked questions
What does a Harlow boiler repair usually cost?
Finding the fault is a fixed £150 + VAT (£180 including VAT), then the repair is priced. Go ahead on the same visit and £70 comes off.
How hard is the water in Harlow?
Very hard. Affinity Water’s 2025 averages were 330 mg/l for Harlow North and 310 mg/l for Harlow South.
Do you repair back boilers?
We diagnose them and give you an honest view. Some are worth repairing and some are better replaced.
Why is one end of my terrace colder than the other?
Often the system needs balancing, or sludge is restricting flow in small bore or microbore pipe. We check both.
Can I top up the boiler pressure myself?
Yes, using the filling loop as your manual shows. If it keeps falling, something is leaking and needs finding.
My housing association boiler has broken. Can you help?
Your landlord is normally responsible for repairing it, so contact their repairs line first.
Which makes do you repair?
All the common makes, whoever installed them.
My combi hot water goes hot then cold. Why?
In very hard water this is often scale on the plate heat exchanger. It is usually repairable once confirmed.
How can I check the engineer is qualified?
Ask to see their Gas Safe ID card. It shows their photograph and the gas work they can do.
Is the repair guaranteed?
Yes, our labour is guaranteed for 12 months.
What is the knocking in my Harlow boiler when the heating starts?
Most likely kettling: very hard water or sludge has narrowed the heat exchanger and water is boiling inside it. Have it looked at before the heat exchanger gives out.
Areas we cover around Harlow
We repair boilers across CM17 to CM20, in Old Harlow, Mark Hall, Netteswell, Latton, Tye Green, Potter Street, Great Parndon and Little Parndon.
Church Langley, Newhall, Gilden Park, Sumners and Katherines are covered as well. More is on our Harlow page.
Harlow boiler not working
Call 01462 506 374 with the boiler make and the code on its display. The fixed diagnostic price is confirmed before a Gas Safe engineer is booked for your Harlow home.
Related services
Annual service, £99 + VAT
Fixed price swaps from £2,375 + VAT
Sludge out, heat back, from £595 + VAT
Cold radiators, pressure loss, noises
Fault codes and guides
Every rate, published