replacing a combi boiler

[waterboy]

I have an ariston euro combi (A/23 MFFI) the prob is I have a leak at the DHW outlet at the point where it enters the (what I think is the diverter valve). I would like to know how the pipe is fixed into this valve and would it be possible just to tighten the joint?. I am a Plumber but only do bathrooms and showers, so this is all new to me!! any suggestions would be great and how would i go about draining the boiler?
Andy.

 

[oilman]

I am a Plumber but only do bathrooms and showers,.........

I'm NOT a plumber, what sort of training did you have that avoided joints on diverter valves?

 

[ChrisR]

Dunno which joint you mean - the DHW doesn't go INTO the diverter! But either way the two 1/2" connections have high temp "fasit" type washers. Same size as 1/2" flexy tap cpnnector washers, which would probably be fine. If its the joint which goes onto the DHW heat exchanger , it will have gone tight because the dhwhe is steel. Sure, though, try doing it up!

The tap water copnnectors are the two on the spaceship-disc (8 screws)shaped part of the diverter valve

On any oldish combi don't use the pressure relief pipe to drain it, or the boiler isolators, or CW inlet isolator, which are underneath the thing. They will leak if you do.

If you're sure it's a tap water joint you don't have to drain the heating side, just turn the mains off and open a tap which is lowr than the combi so when you break the seal it'll suck air in.