Potterton performa he 28 intermitent hot water flow

[davygravy]

Hi, hope someone can help, when I turn on the hot water the water doesn't seem to get hot, as boiler flares up it soon goes of then back on again and never reaches the desired temperature, thanks

 

[gas112]

blocked plate heat exchanger by sounds of it , needs cleaning

 

[davygravy]

Cheers, is it a big job or relatively easy?