Boiler losing pressure in Theydon Bois? Heating upgrades sorted properly
If you're topping up your boiler in Theydon Bois every week or two, you have a system leak — usually small and hidden. We pressure-test the system, locate the source and fix it properly so you stop refilling. Heating upgrade work in Theydon Bois usually means power-flushing, smart controls, TRVs or radiator replacements — we'll tell you straight which actually move the dial for your system.
You're not getting a call centre — you're getting Grant.
The same engineer quotes the job, does the work, and answers the phone afterwards if anything's not right.
Gas Safe Registered
Every gas job legally signed off
18+ years on the tools
Grant has been fixing boilers in Harlow since before smart thermostats existed.
Real human on the phone
Most calls answered the same day, often within the hour.
Locally based in Theydon Bois
Not a national chain — your local engineer, your local prices.
If you're topping up your boiler in Theydon Bois every week or two, you have a system leak — usually small and hidden. We pressure-test the system, locate the source and fix it properly so you stop refilling. Heating upgrade work in Theydon Bois usually means power-flushing, smart controls, TRVs or radiator replacements — we'll tell you straight which actually move the dial for your system.
Trusted for heating upgrades across Theydon Bois
Our heating upgrades work in Theydon Bois is built around three things: doing it properly, charging fairly, and being there afterwards if you need us.
That last bit matters — a lot of installers vanish the moment the invoice clears. We don't.
If something plays up in the first year, we come back and sort it. No quibbles, no callout fee.
About Theydon Bois
Period village stock with modern detached infill.
- Forest-edge conservation considerations
- Older system replacements
What's included
Power Flushing
Deep clean of central heating to remove sludge and restore efficiency.
Learn moreRadiator Replacement & Relocation
Swapping tired old radiators or moving them for new layouts.
Learn moreSmart Thermostat Installation
Hive, Nest, Tado, Honeywell — fitted, set up and explained.
Learn moreMagnetic System Filter Fitting
MagnaClean or Spirotech filters to protect your boiler from sludge.
Learn moreWhat you get when you book us
- Rebalancing included with every flush
- Sentinel X100 inhibitor used as standard
- BTU sizing calculations for radiator changes
- Smart thermostat brand-agnostic — Hive, Nest, Tado, Honeywell, Drayton
- Boiler Plus compliant installs
Working with us on a heating upgrades job in Theydon Bois
Listen first
Cold spots? Noisy boiler? Cold rooms upstairs? We diagnose what's actually wrong before suggesting fixes.
Recommend the right upgrade
Sometimes it's a £150 magnetic filter, sometimes a £600 power flush, sometimes new radiators. We'll be straight with you.
Do the work cleanly
Floors covered, water drained properly, no mess left behind.
Show the before/after
Pressure readings, radiator temps, and inhibitor levels all logged so you can see the difference.
Quick answers on heating upgrades in Theydon Bois
How often should I need to top up?▾
A healthy sealed system should hold pressure for 6-12 months between top-ups. Anything more frequent points to a leak.
Could it be the expansion vessel?▾
Yes — a perished expansion vessel inside the boiler is a common cause. We test the vessel as part of diagnosis.
Do I really need a power flush?▾
If radiators have cold patches, your boiler is noisy, or you're fitting a new boiler to an older system, yes. Otherwise a chemical flush and magnetic filter is often enough.
How much does a power flush cost?▾
Typically £450–£750 depending on system size and number of radiators. We give a fixed price after a quick survey.
Our other services for Theydon Bois homes
Boiler installs in Theydon Bois
Worcester, Vaillant, Ideal and Glow-worm boilers fitted by Gas Safe registered engineers — sized properly, fitted neatly, and backed by manufacturer warranties of up to 12 years.
Boiler repairs in Theydon Bois
No heating or hot water? We respond fast — usually same day — diagnose properly, and give you a fixed price before any work starts.
Boiler servicing in Theydon Bois
Annual servicing keeps your boiler safe, efficient, and your manufacturer warranty valid. Full inspection, combustion analysis, and a written report.
Plumbing in Theydon Bois
Everyday plumbing done properly — taps, toilets, leaks, washing machines, showers, outside taps and isolation valves.
Areas near Theydon Bois we also cover
At a glance
- Service
- Heating Repairs & Upgrades
- Coverage
- Theydon Bois (CM16) and surrounding areas
- Response time
- Usually within 24–48 hours
- Credentials
- Gas Safe registered, fully insured, 12-month workmanship guarantee
- Pricing
- Fixed written quotes, no surprise extras
Roughly what you'll pay in Theydon Bois
These are honest starting prices for jobs we do every week. Final quote depends on your property — we'll always confirm in writing before any work starts. No surprise add-ons.
| Job | Price |
|---|---|
Single radiator swap supply & fit, like-for-like | from £180 |
Smart thermostat install (Hive/Nest/tado) wired in and configured | from £220 |
Full magnetic filter & power flush extends boiler life, lower bills | from £450 |
TRV upgrade per radiator fitted while system drained | from £45 |
Prices include VAT. Parts quoted separately and shown on your written quote.
Other ways Theydon Bois customers find us for heating upgrades
Same engineer, same fixed pricing — different question, different answer.
Stop the pressure drop in Theydon Bois
Free written quote, no obligation. Real engineer, fixed price, fast response.