Common failures on ECO funded boiler installs and how to avoid them

Throughout ECO there has always been high numbers of fails raised under the following OFGEM Set question - HSNB.2 Has the boiler been installed as per manufacturer’s instructions and other guidance.

The question is very broad, therefore a lot of points can be addressed under this questions, however the most common faults are in regards to the condensate connection.


The most frequent mistakes

1. Condensate not insulated outside

Condensates should always be insulated when running outside, this is to stop the condensate freezing in colder temperatures.

If the condensate is not insulated and it does freeze, this can cause issues with the boiler where the condensate is not able to discharge causing the boiler to stop working.


2. Condensate not secured to the wall

Condensates should always be secured with brackets to the wall, this is to stop it falling off. This in turn could cause issues where the inside is able to freeze causing the boiler to fail.


3. Condensate not 32mm through the wall

Condensates should always be upgraded when going through an external wall to the outside of the property, again this helps to avoid freezing within the condensate.


4. Condensate not 32mm in unheated areas

Condensates in unheated areas (such as a loft) should always be treated as external. This means the condensate must be run in 32mm as soon as possible under the boiler again this avoids freezing within the condensate which could cause the boiler to fail.


5. Condensate not insulated in unheated areas

Condensates in unheated areas (such as a loft) should always be treated as external therefore the condensate should always be insulated in these areas.


6. Condensate must go to external drain/soak away/ internal connection

Condensates should always terminate in either an external drain, soak away or internal connection. It should go the full way to these connections and not be cut short, remembering that if situated in an unheated or external space, the insulation is applied to the pipe for the full distance.


7. Condensate must be sloped

When running the condensate from the boiler, this should always be kept at a constant slope to make use of gravity.

Exceptions are made when using condensate pumps to pump the condensate away.

This avoids the contents of the condensate running back into the boiler, which causes issues.


To remember...

OFGEM Guidance can vary from manufacture instructions. Requirements set by OFGEM must be adhered to.

Where practicable, an internal connection for the condensate is always preferred, always remember to provide evidence for why this was not suitable in your submission should a failure arise.


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