Posted by: @editor

↑

Things have gone quiet with you @drei. Any updates?

Just a brief update to keep things transparent.

Section 75 (MBNA)

• My Section 75 claim is still ongoing.

• MBNA have all the evidence: independent expert assessment, multiple remedial quotes (including Heat Geek Elite installers), radiator sizing errors, buffer temperature losses, and energy-use data.

• I am awaiting their final decision so remedial works can proceed.

EPC Improvements

• Following my Subject Access Request in September, EPC briefly re-engaged in November.

• I shared clear data, calculations, and manufacturer-backed evidence and asked them to confirm whether they agreed or disagreed.

• Communication stopped the same day (10 November) and only resumed weeks later to say they would “review the data”.

• As of now, no technical response or remediation proposal has been provided.

System Performance (Actual Data)

• I now have over two years of logged data directly from the heat pump.

• Monthly SCOP has consistently sat between 1.9 and 2.5, averaging around 2.3.

• This is well below the 3.9 SCOP stated in EPC’s design documentation.

• Cold months continue to cost £400–£600 per month, with supplementary electric heaters still required.

Where Things Stand

• This is now the third winter with an underperforming system.

• The issues have been independently verified by multiple qualified engineers.

• I am simply waiting for MBNA to conclude the claim so I can proceed with proper remedial work and finally have a functional heating system.

One further point worth noting is that system performance has only improved after I increased the weather compensation curve and allowed the heat pump to run at much higher flow temperatures (up to 60 °C). While this has resulted in improved comfort and a modest increase in observed SCOP compared to the first winter, it effectively means the system is now operating closer to a high-temperature boiler regime rather than as a properly designed low-temperature heat-pump system. Even in this configuration, we still rely on a continuously running 2.8 kW oil-filled electric radiator in the living room to maintain comfort. This reinforces the conclusion that the original emitter sizing and hydraulic design are fundamentally inadequate, and that acceptable comfort is only being achieved by sacrificing efficiency and supplementing the system with direct electric heating.

I’ll update again once a final outcome is reached.

Posted by: @editor

↑

Things have gone quiet with you @drei. Any updates?

Just a brief update to keep things transparent.

Section 75 (MBNA)

• My Section 75 claim is still ongoing.
• MBNA have all the evidence: independent expert assessment, multiple remedial quotes (including Heat Geek Elite installers), radiator sizing errors, buffer temperature losses, and energy-use data.
• I am awaiting their final decision so remedial works can proceed.

EPC Improvements

• Following my Subject Access Request in September, EPC briefly re-engaged in November.
• I shared clear data, calculations, and manufacturer-backed evidence and asked them to confirm whether they agreed or disagreed.
• Communication stopped the same day (10 November) and only resumed weeks later to say they would “review the data”.
• As of now, no technical response or remediation proposal has been provided.

System Performance (Actual Data)

• I now have over two years of logged data directly from the heat pump.
• Monthly SCOP has consistently sat between 1.9 and 2.5, averaging around 2.3.
• This is well below the 3.9 SCOP stated in EPC’s design documentation.
• Cold months continue to cost £400–£600 per month, with supplementary electric heaters still required.

Where Things Stand

• This is now the third winter with an underperforming system.
• The issues have been independently verified by multiple qualified engineers.
• I am simply waiting for MBNA to conclude the claim so I can proceed with proper remedial work and finally have a functional heating system.

One further point worth noting is that system performance has only improved after I increased the weather compensation curve and allowed the heat pump to run at much higher flow temperatures (up to 60 °C). While this has resulted in improved comfort and a modest increase in observed SCOP compared to the first winter, it effectively means the system is now operating closer to a high-temperature boiler regime rather than as a properly designed low-temperature heat-pump system. Even in this configuration, we still rely on a continuously running 2.8 kW oil-filled electric radiator in the living room to maintain comfort. This reinforces the conclusion that the original emitter sizing and hydraulic design are fundamentally inadequate, and that acceptable comfort is only being achieved by sacrificing efficiency and supplementing the system with direct electric heating.

I’ll update again once a final outcome is reached.