ideal mini 24 combi

[CLARKO]

hi, i have the above boiler , problem is the there is no hot water.the heating side works perfect the boiler does not make any noise when hot water is called for . the flow rate of water coming out of the hot tap is very poor would this indicate a scaled up dhw heat exchanger. would the poor flow rate be enough not to trigger the flow sensor hence no clicking sound from the boiler .

cheers

 

[croydoncorgi]

Where do you live? (If the water supply is very hard it is possible (but not likely) that the hot water side of the secondary heat exchanger on your boiler is limescaled)

Is there a 'scale reducer' (usually cylinder 20 -30 cm long, marked accordingly) fitted on the cold supply to the boiler? (Interestingly, the manual for your boiler rules out use of 'artificially softened water' for the cold supply!)

Most of the blockages of heat exchangers on Combi boilers are on the 'primary' side (ie, particles of oxide scale from radiators get into the narrow passages of the HX and block it physically). Limescale in the secondary half of the HX is uncommon. Blockage on the primary side of the HX would NOT stop the boiler from firing: the usual symptoms would be cool (but not cold) water out the hot tap and the boiler cycling on and off.

A filter and flow limiter are fitted in the HW circuit of the boiler. If hot water flow is 'very poor' it's quite possible it's too slow to trigger the flow switch which turns the boiler on. The filter may be blocked. Dismantling the boiler to get at the filter involves removing the gas valve and is therefore a 'CORGI job'. Check that the valves supplying the boiler with cold water are fully on and there's no other reason outside the boiler for poor flow.

 

[CLARKO]

thanks for your post croydoncorgi,i will strip down the gas valve and clean filter as i am corgi registered. they don't teach you everything there is to know on the ccn1 about boilers etc .i only got my corgi 6 months ago i ve got alot to learn yet but thank you for your help

 

[croydoncorgi]

No no!
I said that the gas valve had to be removed to get at the inlet filter and flow restrictor!
It's not actually IN the gas valve!
The gas valve is a sealed unit and not to be opened at all, ever.

RTFM (Read The Fine Manual)!