Professional HIU Replacement
& New HIU Installation
We provide HIU installation and HIU replacement in London for communal and district heating systems. From supply-and-fit replacements to new installs, we handle removal, fitting, commissioning, recommissioning and performance checks for heating and hot water, with clear documentation provided.
What’s included in HIU installation and replacement
Our HIU replacement and installation service is designed to make the process straightforward from survey through to final commissioning. Whether you need a failed Heat Interface Unit replaced or a new HIU installed within an existing communal heating scheme, we confirm compatibility, carry out the installation properly, and verify heating and hot water performance before handover.
If you want a quote quickly, the best starting point is to send a clear photo of the HIU label together with a short description of what you need. That helps us identify the make, model and likely compatibility before arranging attendance.
- Pre-install checks and safe isolation of supplies
- Removal and disposal of the old HIU
- Supply and installation of the new HIU as quoted
- Connection of pipework, services and wiring where applicable
- Commissioning and performance checks for heating and hot water
- Written commissioning and completion documentation in PDF format
When HIU replacement is the better option
Repair is often the best option when the fault is isolated and parts are available. Replacement may be more suitable when the HIU has repeated failures, obsolete parts, poor performance caused by internal wear, or when repair costs start to approach replacement value.
Repeated HIU Faults
If the unit is breaking down repeatedly, replacement can often be more cost-effective than continuing with repeated repair visits and part changes.
Obsolete or Hard-to-Source Parts
Some HIU models become uneconomical to keep once key components are discontinued or difficult to source within a sensible timeframe.
New Layouts & Refurbishments
We can also install HIUs for new layouts and refurbishments within communal heating schemes, subject to site survey and system specification.
What we do on HIU replacement and new installs
Every installation includes commissioning and performance testing to confirm stable temperatures, correct operation and reliable hot water delivery. That means the job is not just about fitting a new box on the wall. It is about making sure the new Heat Interface Unit is suitable, commissioned correctly and working properly before handover.
Most common and reliable HIUs in the UK market
The current page highlights several HIU models commonly used for replacement and installation projects, including Baxi, Modutherm, Ecolino, Caleffi, Evinox and Danfoss. Warranty terms vary by brand and model, typically from 2 to 5 years, with some extended options available.
Baxi AQUAHEAT HI/HWI
- Labour and materials included
- Indirect HIU
- Dual plate heat exchanger
- User interface control
- Compact and easier to maintain
Modutherm MTA ECO / MTA Plus
- Smart HIU options available
- Heat pump optimised variants
- Dual plate heat exchanger
- Low maintenance and compact
- Self-diagnostic capability
Evinox ModuSat
- Smart HIU format
- Efficient and compact
- Low maintenance
- Suitable for many replacement projects
- Commonly used in communal systems
Caleffi SATK 32
- Dual plate heat exchanger
- User interface control
- Compact design
- 80KW DHW / 10KW HTG variant shown
- Suitable for selected replacement programmes
Danfoss HIU
- Labour and materials included
- Dual plate heat exchanger
- Mechanical controls
- Efficient and widely recognised brand
- Suitable where compatibility is confirmed
Intatec Hiper II
- Frequently found in communal heating flats
- Compatibility confirmed before booking
- Suitable for replacement projects
- Clean, compact cupboard fit
- Survey recommended before final quote
HIU installation and replacement FAQs
How much does HIU installation cost in London?
Costs depend on the HIU model, pipework changes and commissioning requirements. The current page says that full HIU replacement and installation usually falls between approximately £1,800 + VAT and £4,500 + VAT, with a confirmed quote provided once site and model details are checked.
Do you supply the HIU or can I supply it?
Both options are possible. We can supply and fit the HIU, or fit a client-supplied HIU provided it is compatible with the communal system and project specification.
How long does HIU replacement take?
Most HIU replacements are completed in a single visit, subject to access, cupboard layout, pipework condition and system requirements. Expected duration is usually confirmed once the site details are reviewed.
Do you commission the HIU after installation?
Yes. The current page confirms that every installation includes commissioning or recommissioning, together with heating and hot water performance checks and settings verification.
What warranty comes with a new HIU?
Warranty is manufacturer-dependent and varies by brand and model, typically between 2 and 5 years, with extended options available on some models. The exact warranty is confirmed in writing at quotation stage.
What do you need to provide a quote?
Ideally send the property postcode, access details, a clear photo of the HIU label, whether it is a replacement or new install, any symptoms, site requirements such as parking or permits, and preferred appointment dates.
What customers say about our HIU work
Reviews help build trust for both residential and commercial customers considering HIU replacement, new installs, repairs or commissioning.
Need a HIU replacement quote or free survey?
Contact us for HIU replacement, new HIU installation, recommissioning and compatibility checks in London. The quickest way to get started is to send a clear photo of the HIU label together with a short description of the work required.