Optional Recommended Services
I-HEATPUMP provides independent, data-led, field-based commissioning, servicing, and diagnostics for real-world heat pump systems.
These services are designed for residential and commercial clients who value measured performance, system reliability, and long-term efficiency, not assumptions.
Our standard services are an excellent starting point. The optional services described below are for those demanding deeper optimisation, or assurance of exceptional heat pump performance.
Verify – Diagnose – Fix – Learn
Heat Pump Heat Exchanger Flush Treatment
Free flowing heating fluid, circulating at the correct rate for your heat pump system is essential to help unlock efficient operation and minimise running costs. Heat exchangers are critically important components fitted to your system. Regular, routine, specialist maintenance is the best way to help ensure blocked heat exchangers and reduced flow rates don’t cause unexpected break downs and poor efficiency.
Gas, oil and direct wet electric heating systems can suffer from blocked heat exchangers too. Sometimes these issues can be less obvious until a critical breakdown occurs because these systems don’t always include as sophisticated flow and temperature monitoring sensors - unlocking 300%+ energy efficiency (as heat pumps can) requires careful monitoring and control.
If you’re interested in learning more about heat pump heat exchangers and their importance, we answer common questions below, including:
1.
What is a heat pump heat exchanger?
2.
Why does heat exchanger performance matter?
3.
What are the symptoms of a blocked heat pump heat exchanger?
4.
How do heat pump heat exchangers get blocked?
5.
Why do we recommend preventative treatment of heat pump heat exchangers?
6.
What does a heat pump heat exchanger treatment involve?
7.
How long does a heat pump heat exchanger treatment take?
8.
Under What Circumstances Is a Heat Exchanger Treatment Not Available?
9.
Why do we recommend booking heat pump heat exchanger treatments in advance?
10.
What's our refund policy for unaffected heat exchangers?
1. What is a heat pump heat exchanger? 2. Why does heat exchanger performance matter? 3. What are the symptoms of a blocked heat pump heat exchanger? 4. How do heat pump heat exchangers get blocked? 5. Why do we recommend preventative treatment of heat pump heat exchangers? 6. What does a heat pump heat exchanger treatment involve? 7. How long does a heat pump heat exchanger treatment take? 8. Under What Circumstances Is a Heat Exchanger Treatment Not Available? 9. Why do we recommend booking heat pump heat exchanger treatments in advance? 10. What's our refund policy for unaffected heat exchangers?
1. What Is a Heat Pump Heat Exchanger?
Heat exchangers are critical components inside your heat pump that allow heat to be transferred from one part of the system to another without the fluids mixing. There are several heat exchangers in your heat pump system - for air to water systems, the type we are most concerned about during a routine service or diagnostic investigation are plate heat exchangers (PHEX).
The radiators or underfloor heating in your home are also heat exchangers - they transfer heat from the heating fluid to the air without direct contact.
In simple terms:
Heat is passed through little passages between a stack of thin metal plates
Water flows on one side, refrigerant (or another water circuit) on the other
The heat exchanger is where useful heat is actually delivered to your home
For every heat exchange, there is a small energy loss - the transfer can never be 100% efficient
If the heat exchanger/s aren’t working efficiently, the entire system suffers - even if everything appears to be running well, at best your system won’t be working as efficiently as it could, and at worst, it could be heading for a breakdown.
2. Why Does Heat Pump Heat Exchanger Performance Matter?
Your heat pump relies on efficient heat transfer to operate economically and reliably. To achieve the high returns in efficiency that heat pumps offer, they rely on free flow of heating fluid at the correct rate.
Blocked heat exchangers impact gas, oil and wet direct electric systems too - sometimes the impact may be less obvious because these systems often don’t benefit from as sophisticated sensing equipment.
When the heat exchanger is clean and fluids are flowing through it properly:
Heat moves easily through the plates
The system runs well at lower temperatures and pressures
Electrical consumption is reduced
Wear on the compressor is minimised
When it becomes partially blocked or fouled:
Heat struggles to move across the plates
Flow is restricted
The heat pump has to work harder to achieve the same result
Over time, this can increase running costs, reduce system lifespan or even cause unexpected breakdowns.
3. What Are Symptoms of a Blocked or Restricted Heat Pump Heat Exchanger?
A partially blocked heat exchanger often goes unnoticed because the system may still “work”, just less efficiently.
Common signs include:
Reduced heating or hot water performance
Longer run times or more frequent cycling
Poor temperature recovery
Higher electricity usage
Flow-related fault codes or unexplained alarms
Unexpexted temperature differences across the heat exchanger
In many cases, these symptoms are gradual rather than sudden, but when the blockage reaches a critical point, the heat pump will usually generate a fault code and cease to operate until the blockage is reduced or removed.
4. How do Heat Pump Heat Exchangers Get Blocked?
Over time or in the case of poorly cleansed new systems, immediately, debris can circulate within heating systems, including:
Installation residues (flux, solder, jointing compounds)
Degraded glycol or corrosion by-products
Fine particulate matter not captured by strainers
Rubberised particles from seals and hoses
Plate heat exchangers have very narrow flow channels, so even small amounts of debris can reduce performance. Proper, thorough system cleansing on commissioning can help reduce the impact of debris on system performance.
Magnetic, vortex or in-line strainers can help collect these particles throughout the systems operational lifetime, but without careful, periodic maintenance, these can become overwhelmed and the system performance can deteriorate slowly or sometimes surprisingly quickly.
Heat pump heat exchangers become blocked because of poor commissioning practices and poor planned maintenance.
5. Why Do We Recommend Preventative Treatment?
Regular inspection and cleaning:
Helps maintain proper heat transfer
Reduces thermal and hydraulic stress on the system
Supports efficient, low-temperature operation
Can prevent avoidable faults and call-outs
Most manufacturer warranties do not cover blocked heat exchangers and they may charge for attending a breakdown due to poor flow
This is especially relevant for systems that:
Use glycol or antifreeze
Have experienced unexplained performance issues
Have had previous system modifications
Haven’t been properly flushed and checked during commissioning procedure
6. What Does Heat A Heat Pump Heat Exchanger Treatment Involve?
If pre-booked, the heat exchanger treatment is carried out during your service visit and includes:
Initial inspection
Visual checks and, where appropriate, internal inspection using specialist tools
Controlled back-flushing
Water is circulated in reverse through the heat exchanger
Dislodged debris are captured in an external filter
Cleanser treatment (if required)
A specialist, system-safe, food-grade cleaner may be circulated for stubborn residues
Thorough flushing follows to remove all residues
Internal heat exchanger inspection (if required)
Flow check in hot water mode & comparison against target & commissioning record (if available)
Inspection of magnetic filter and housing
Bore-scope inspection of hot water plate heat exchanger (if evidence suggests blockage)
Verification
Flow checks before and after
Photographic or video evidence of debris in-situ and post-removal (where present)
Evidence included in digital report
All work is carried out gently, within safe pressure limits and without disturbing the elements of the system inside the property.
7. How Long Does a Heat Pump Heat Exchanger Treatment Take?
The duration of a heat pump heat exchanger treatment depends on system size, condition, and accessibility, but in most cases the process can be completed within a single site visit.
For typical residential systems, a heat exchanger treatment usually takes between one and three hours. This includes system preparation, controlled circulation of the treatment fluid, and verification that normal flow and heat transfer characteristics have been restored.
Systems with heavier fouling, restricted flow, or complex hydraulic layouts may require additional time. Where significant contamination is present, treatment may be staged or combined with further diagnostic checks to ensure the underlying cause has been addressed.
On completion of the treatment process, system operation is monitored to confirm that the system function has not been impaired, and ideally has been improved. Pump speeds are adjusted (if required) and the evidence is recorded and included in the engineer report.
8. Under What Circumstances Is a Heat Exchanger Treatment Not Available?
If the heat pump system is under a live or recent fault condition related to poor flow that has not been fully resolved
If the system is suffering from, suspected to suffer from or might reasonably be considered to be suffering from symptoms that may be a sign of system wide contamination and blockages
A good indication of system-wide issues with contamination are if it’s been verified the system is free from air, but heat remains intermittent and patchy from emitters (radiators and/or under floor heating loops).
If either of these conditions are true, or you’re unsure - contact us ahead of booking to avoid disappointment - an emergency appointment to focus on verification, diagnosis & potential resolution might be the better option.
9. Why Do We Recommend Booking Heat Pump Heat Exchanger Treatment in Advance
Heat exchanger cleaning takes additional time and equipment preparation.
By booking ahead:
We can guarantee sufficient time is available during your visit for the proper procedure to be followed
We arrive prepared with the correct equipment and consumables
The work can be carried out efficiently without rushing
The additional cost is less than a standalone return visit
If not pre-booked, we may not always be able to accommodate the treatment on the day.
10. What Is Our Fair Pricing & Partial Refund Policy On Heat Exchanger Flush
Inspection of the in-line filters (where present) is included as part of your service. Condition of the filters is usually (not always) a good indicator of whether there is likely to be significant contamination of the heat exchanger.
If you pre-book a heat exchanger treatment and no debris or restrictions are found in the heat exchanger, we will:
Collect photographic evidence
Refund the cleaning element of the charge (75% of Heat Exchanger Flush cost)
This ensures you’re never paying for unnecessary work, while still allowing us to allocate time and resources responsibly.
Our Approach
We believe in:
Inspecting before intervening
Using evidence to guide recommendations
Improving performance without unnecessary work
If cleaning is needed, you’ll see why. If it isn’t, you won’t be charged for it.
Anti-Corrosion Treatment
1. What Is Heat Pump Corrosion?
Corrosion is the gradual degradation of metal caused by chemical reactions with its environment. In heat pump systems, this most commonly occurs when moisture, oxygen, contaminants (such as salt), or aggressive water chemistry interact with steel, copper, aluminium, or mixed-metal components.
Left unchecked, corrosion can attack heat exchangers, pipework, fixings, coils, and internal components - often invisibly at first.
2. Why Corrosion Matters
Corrosion isn’t just cosmetic - even minor corrosion can:
Reduce heat transfer performance
Increase electrical and mechanical strain
Cause refrigerant or water leaks
Shorten component lifespan
Lead to unexpected and costly failures
In external units especially, corrosion accelerates due to constant exposure to weather, airborne salts, pollutants, and seasonal temperature swings.
3. Why We Recommend Regular Treatment
Preventative corrosion treatment is far more cost-effective than reactive repair or replacement. Regular protection (especially in harsh environments like coastal areas):
Slows oxidation and material breakdown
Preserves system efficiency and performance
Extends the service life of evaporator coils and components
Reduces the likelihood of unexpected breakdowns
Think of it as protecting the asset value and maximising the longevity of your heat pump, not just maintaining appearances.
4. What the Treatment Involves
Our standard service includes internal and external cleaning using the appropriate product for the equipment condition. A typical corrosion protection treatment goes further and includes:
Application of 4 specialist corrosion-inhibiting coatings - each appropriate for the protection level required, material composition and aesthetic finish
Targeted protection of coils, fixings, structural trays, exposed metalwork & key mechanical parts
All treatments are selected to be compatible with heat pump materials and normal operating temperatures.
5. Why We Recommend Booking in Advance
Corrosion protection is most effective when applied before damage takes hold. Booking in advance:
Allows the treatment to be combined efficiently with routine servicing & cleansing
Allows sufficient allocation of time and materials to complete the treatment professionally
Helps ensure sufficient stocks of specialist coatings are available when needed
Reduces the risk of avoidable future call-outs
Early intervention keeps your system operating efficiently and reliably - year after year.