Three Companies Declined The Job – The Problem Wasn't The Heat Pump

Three Companies Declined The Job – The Problem Wasn’t The Heat Pump

A homeowner contacted us after losing heating completely at their property. They had already been dealing with the problem for some time, not just with the lack of heating, but with the difficulty of finding anyone willing to investigate it.

Three local companies had already declined to attend. As soon as each was told the property had a heat pump, they turned the job down, explaining they did not work on heat pumps or that the problem was outside their scope.

The homeowner was understandably worried. They had assumed the heat pump unit must have failed and were concerned about the potential cost of a specialist repair or replacement.

After contacting us for an independent technical opinion, we arranged a brief review to understand exactly what was happening before any further action was taken.

Our Investigation

Before the call, the homeowner sent several photographs of the installation, the plant room, and the controller display. They also described the symptoms clearly: the heat pump appeared to be running, hot water was working normally, but the central heating was producing nothing at all.

We then arranged a short video call to review the system together, walking through the controls and visible pipework in real time.

Within a few minutes of going through the setup together, a clear picture emerged:

• The heat pump was operating normally and displaying no fault codes at all

• Hot water was working correctly and the cylinder was reaching its target temperature

• The controller was actively calling for heating and sending a demand signal throughout

• Despite the demand being active, no heat was reaching the heating circuit or the radiators

• The heating circuit was not receiving heat.

This combination pointed to a specific and identifiable problem: the heat pump was doing its job correctly, but something between the heat pump and the radiators was preventing that heat from reaching them.

The heat pump was ruled out within the first few minutes. Attention then shifted to what lay between it and the heating circuit.

What We Found

Working through the controls and pipework layout during the video call, we identified that the zone valve serving the central heating circuit was not opening when a demand was active. It was remaining in the closed position, blocking all flow to the radiators.

The heat pump was producing heat as it should. That heat was entering the pipework, reaching the zone valve, and going no further. With the valve stuck closed, there was no route for that heat to travel into the heating circuit, so nothing reached the radiators regardless of how long the system ran or how high the demand.

This explained everything the homeowner was experiencing: a heat pump that appeared to operate normally, hot water that worked correctly, and a heating system that was completely unresponsive.

This is a pattern we encounter regularly. Because a property has a heat pump, many homeowners and visiting engineers assume any heating failure must originate with the heat pump unit. In practice, the heat pump is frequently not the source of the problem.

Controls, pumps, sensors, and zone valves are standard heating components that can fail independently of the heat pump, producing symptoms that appear on the surface to be heat pump faults. Our article on why heat pump repairs are often misunderstood in the UK explores this pattern in detail and explains how to approach these situations more effectively.

If your home is not reaching temperature despite the heat pump running, the following articles cover the most common causes:

If the property is not warming up at all, our article on why your house is still cold with a heat pump covers the full range of causes and what to check first.

If only some rooms are cold while others heat normally, our article on why some rooms stay cold with a heat pump explains what typically drives that pattern.

The Solution

Once we had established the cause, we gave the homeowner a clear and specific explanation of what had failed and what type of engineer was actually needed to fix it.

Critically, a heat pump specialist was not required. A zone valve is a standard heating component that any competent heating engineer or plumber can diagnose and replace. Calling a heat pump specialist for this type of fault would have been both unnecessary and substantially more expensive.

We explained exactly what the engineer should check, how to identify whether the valve spindle had seized or the motorised actuator had failed, and what the replacement process would involve.

Armed with a clear diagnosis and a description of what needed doing, the homeowner arranged for a local heating engineer to attend.

The engineer inspected the zone valve, confirmed our diagnosis on site, and replaced the faulty component in a single visit.

The Outcome

Heating was restored to the property immediately after the replacement was completed. The radiators came on for the first time in weeks and the home reached a comfortable temperature within a few hours.

The heat pump itself required no attention, no specialist diagnostic visit, and no repairs of any kind. The entire repair was carried out by a standard heating engineer at standard heating rates.

The homeowner also came away with a clearer picture of how their system worked: which components a general engineer could service, and when a heat pump specialist would genuinely be needed.

This case illustrates one of the most common patterns we encounter: a standard heating component failing and being incorrectly assumed, by multiple people, to be a heat pump fault.

Similar patterns appear across other cases we have investigated:

In one case, an elderly homeowner was told repeatedly that her heat pump was fine, when a single misconfigured setting was actually preventing the house from heating. The issue was identified remotely without a site visit.

In another, a household with poor heating and no reliable hot water traced the problem to a faulty cylinder temperature probe rather than any fault with the heat pump unit itself.

A third example involved a homeowner who had paid for repeated engineer visits without the real cause being found, which turned out to be a blocked filter. In all three cases, the heat pump itself was operating correctly throughout.

Key Takeaway

Not every heat pump problem is actually a heat pump problem. This is one of the most important things UK homeowners with heat pumps need to understand.

Zone valves, sensors, circulation pumps, and control components are all standard heating parts that sit within the wider system around the heat pump. Any of them can fail independently, and any of them can produce symptoms that are easily mistaken for a heat pump fault.

A structured diagnosis that looks at the whole system, not just the heat pump unit, can identify these causes quickly and direct homeowners toward the right specialist at the right cost.

If you are struggling to find someone willing to investigate a heat pump problem, or if you have had multiple visits without a clear diagnosis, our Fix My Heat Pump service can identify the actual cause and tell you what type of engineer is needed to fix it.

If you are planning a new installation and want an independent review of the proposed design before any work begins, our Pre-Installation Review service reviews the heat loss methodology, system design, and component specification so potential problems are identified before they become expensive ones.