Condensing combi boiler query.

[jguest]

Hi. Have had new combi boiler fitted. Plumbing has all been rerouted also due to building work. Have realised that when I turn kitchen cold tap off the boiler behaves as though a hot tap has been turned on ie the symbol that shows hot water is being drawn appears briefly and the boiler seems to cut out then reset itself to continue with the central heating. Is this normal ? - have had combi boiler for years and never knew any cold taps to affect the boiler like this.

 

[Agile]

It is usually caused by air trapped in the hot water pipes.

It will probably clear on its own over a few weeks as the air dissolves.

Sometimes it needs a non return valve to be fitted in the DHW flow pipe.

Tony

 

[gas_man_gaz]

what boiler ya got? i had the same fault with a baxi duo-tec which needed a check valve and a mini exspansion vessel fitting

 

[jguest]

Thank you for the prompt replies. The boiler is a Vaillant Ecotec 837. We'll give it a couple of weeks and if it hasn't sorted itself out have a word with the plumber.

 

[David937]

I had the same problem with my Vaillant ecoTEC+ 937 and a very helpful person on this forum advised me to set d88 to 1.