Vaillant ecoMAX Hot & Cold

[afan]

Hi All,

I had a Vaillant ecoMAX installed around 5 years ago and it has been great... up until just before Christmas. Now the hot water temperature drops after about 30-60 seconds and largely remains cold. Cutting the flow to about a 1/4 can heat it up again. This happens on the sink taps, bathroom taps and mixer shower.

There are no errors coming up on the boiler lcd and I can see the tap icon. Pressure seems fine.

I initially thought (or rather hoped) that it was just the outside temperature causing the boiler to struggle, but it was slightly over spec'd for the house to begin with and sas I said previously, has been great until now.

Any idea?

Cheers

Dai

 

[davebgas]

Without seeing it, i'd stump for the plate to plate exchanger being scaled/blocked.
However, could be a few things...

Dave

 

[David937]

Hi All,

I had a Vaillant ecoMAX installed around 5 years ago and it has been great... up until just before Christmas. Now the hot water temperature drops after about 30-60 seconds and largely remains cold. Cutting the flow to about a 1/4 can heat it up again. This happens on the sink taps, bathroom taps and mixer shower.

There are no errors coming up on the boiler lcd and I can see the tap icon. Pressure seems fine.

I initially thought (or rather hoped) that it was just the outside temperature causing the boiler to struggle, but it was slightly over spec'd for the house to begin with and sas I said previously, has been great until now.

Any idea?

Cheers

Dai

When you have a hot water tap open check what temperature the boiler LCD is showing.

 

[afan]

The temprature changes from around 80 down to about 68... ocassionaly warms back up, but goes down again.

 

[David937]

From my limited experience I would say that the plate heat exchanger is blocked.