Hello,
I've got an Ocean Alpha 240eco combi boiler. The DHW has gone tempromental, sometimes it gets hot sometimes not.

I've checked the DHW flow micro-switch, which is operated by the diverter valve. But the actual burner is not igniting, you can hear the pump and fan kick in as well.

The cental heating is working fine by the way.

Anybody got any suggestions as to what is the problem?

Thanks for reading,

Mark, April 2007

did you sort your boiler out? if so what was the problem? as its happening to mine

linda, May 2009

Thanks for the reply. I have the installation and service manual, so I will give it a go.

Thanks again.

Mark, April 2007

THE FAULT IS ALMOST CERTAIN TO BE THE DIRECT HOT WATER TEMPERATURE SENSOR. IT'S LOCATED ON THE HOT WATER OUTLET PIPE JUST UNDER THE SECONDARY PLATE HEAT EXCHANGER. A SMALL SCREW IN THERMISTOR WITH A TINY PLUG ON IT. IF YOU HAVE THE INSTALLATION & SERVICE MANUAL LOOK IN TECHNICAL DATA AT THE BOILER SCHEMATIC DRAWING. (NUMBER 17 ON THE LIST).
TO CHANGE IT ISOLATE THE POWER SUPPLY TO THE BOILER, CLOSE THE COLD WATER SUPPLY COCK & OPEN A HOT TAP TO DRAIN. UNCLIP THE CONNECTOR PLUG FROM THE SENSOR & UNSCREW THE SENSOR FROM THE PIPE. USE A NEW WASHER AND SCREW IN THE NEW ONE. REPLACE THE CONNECTOR PLUG MAKING SURE ITS THE RIGHT WAY ROUND.
OPEN THE COLD WATER SUPPLY COCK & RUN THE HOT TAP UNTIL NO AIR COMES OUT. CLOSE THE HOT TAP, CHECK FOR LEAKS & SWITCH ON THE BOILER. TURN ON A HOT TAP & BOILER SHOULD OPERATE OK.
THIS IS QUITE A COMMON FAULT & THE PART IS CHEAP. LESS THAN £20.

DAVE12, April 2007