Very little hot water

Hi
I have a customer who has a Boilermate II the problem is he runs a bath but can only fill the bath a quarter full
before it goes cold. If he leaves the immersion on constantly he manages to get a full bath of hot water.

I thought it may have been the Hawco thermostat and replaced it. The boiler fired up straight away after i fitted it
but the following day he called me saying he had the same problem. The C/H works ok.

I thought it may have been the blender valve but if the immersion gives him a tank of hot water it cant be.

Any advice would be much appreciated.

Hi kennyd,

This is water scale in the DHW heat exchanger (coil of pipe inside the store). The scale insulates the pipe and stops the domestic water from picking up heat through the wall of the pipe. It needs chemically descaling using a powerflushing pump. Takes a couple of hours once hooked up then new performance will be back.

Cheers, Mike

I have the exact same problem. How much does it cost to get it descaled?

Cheers

Andy

Hi Andy,

It depends where you are and how close you are to a descaling specialist! Once on site, it takes around three hours to carry out the descale at whatever rate your specialist charges, plus £40 or so for chemicals.

Cheers, Mike