House Not Heating Properly Due to Undersized Radiators
House Not Heating Properly Due to Undersized Radiators
House Not Heating Properly Due to Undersized Radiators
House Not Heating Properly Due to Undersized Radiators
House Not Heating Properly Due to Undersized Radiators
Property couldn’t reach temperature due to incorrect heat loss assumptions and undersized radiators.
Property couldn’t reach temperature due to incorrect heat loss assumptions and undersized radiators.
Property couldn’t reach temperature due to incorrect heat loss assumptions and undersized radiators.
House Not Reaching Temperature – Incorrect Heat Loss & Undersized Radiators
The Problem
A homeowner contacted me because their property wouldn’t reach a comfortable temperature during winter.
Even with the system running, the house remained cold — particularly during colder weather.
What I Found
During a video call, I reviewed the system setup, discussed the property, and looked at the radiator sizes.
Straight away, there were concerns around whether the system had been designed correctly.
I asked the homeowner to provide the original heat loss calculation from the installing company.
After reviewing it, the issue became clear:
The heat loss had been based on generic post-2022 insulation assumptions
These did not reflect the actual property
As a result, the system had been under-designed
This led to:
Radiators being undersized
The heat pump struggling to maintain temperature
Poor overall comfort levels
The heat pump itself was also slightly undersized for the actual heat demand.
What I Changed
In the short term, I guided the homeowner through adjusting the system to improve performance:
Increased flow temperature temporarily to help the system maintain heat
Explained how to manage the system during colder periods
I then carried out a more accurate heat loss assessment using available property data and the EPC.
From this, I provided:
Correct radiator sizing recommendations
Guidance on system operation
Advice on using the built-in booster heater effectively, so it would only operate during colder conditions
I also provided guidance on next steps under MCS, advising the homeowner to take the findings back to the installing company.
The Outcome
Following a further discussion with the installer, the issue was acknowledged as a design error.
The installing company returned to site and:
Upgraded the radiators
Corrected the system design
Replaced the heat pump for a larger KW one
All work was completed at no additional cost to the homeowner.
The system was then able to heat the property properly, and comfort levels improved significantly.
House Not Reaching Temperature – Incorrect Heat Loss & Undersized Radiators
The Problem
A homeowner contacted me because their property wouldn’t reach a comfortable temperature during winter.
Even with the system running, the house remained cold — particularly during colder weather.
What I Found
During a video call, I reviewed the system setup, discussed the property, and looked at the radiator sizes.
Straight away, there were concerns around whether the system had been designed correctly.
I asked the homeowner to provide the original heat loss calculation from the installing company.
After reviewing it, the issue became clear:
The heat loss had been based on generic post-2022 insulation assumptions
These did not reflect the actual property
As a result, the system had been under-designed
This led to:
Radiators being undersized
The heat pump struggling to maintain temperature
Poor overall comfort levels
The heat pump itself was also slightly undersized for the actual heat demand.
What I Changed
In the short term, I guided the homeowner through adjusting the system to improve performance:
Increased flow temperature temporarily to help the system maintain heat
Explained how to manage the system during colder periods
I then carried out a more accurate heat loss assessment using available property data and the EPC.
From this, I provided:
Correct radiator sizing recommendations
Guidance on system operation
Advice on using the built-in booster heater effectively, so it would only operate during colder conditions
I also provided guidance on next steps under MCS, advising the homeowner to take the findings back to the installing company.
The Outcome
Following a further discussion with the installer, the issue was acknowledged as a design error.
The installing company returned to site and:
Upgraded the radiators
Corrected the system design
Replaced the heat pump for a larger KW one
All work was completed at no additional cost to the homeowner.
The system was then able to heat the property properly, and comfort levels improved significantly.
Contact Us
Not Sure If We Can Help?
Not Sure If We Can Help?
Not Sure If We Can Help?
Not Sure If We Can Help?
Not Sure If We Can Help?
If you're unsure whether your heat pump problem can be diagnosed remotely, send us a short description of the issue and we’ll let you know if a technical review is worthwhile. No obligation.
If you're unsure whether your heat pump problem can be diagnosed remotely, send us a short description of the issue and we’ll let you know if a technical review is worthwhile. No obligation.
If you're unsure whether your heat pump problem can be diagnosed remotely, send us a short description of the issue and we’ll let you know if a technical review is worthwhile. No obligation.
