Heatline Vizio 24

[Mark raig]

Ive been asked to have a look at a heatline Vizo 24 Combi. The problem is an intermittent fault on the DHW system. Ive tried the fault finding section in the manual. The flow lts \ min is fine though the presure seems rather low the 3 way valve is operating as it should when it works which leaves according to the manual the PCB or the flow switch is there anyway of testing or fooling the board to think the flow switch is working so I can eliminate at least one or the other regards

Mark

 

[Billy Bob Bob]

Ive been asked to have a look at a heatline Vizo 24 Combi. The problem is an intermittent fault on the DHW system. Ive tried the fault finding section in the manual. The flow lts \ min is fine though the presure seems rather low the 3 way valve is operating as it should when it works which leaves according to the manual the PCB or the flow switch is there anyway of testing or fooling the board to think the flow switch is working so I can eliminate at least one or the other regards

Mark

is it a diaprahm flow switch with 2 wires?

 

[Mark raig]

No its got 3 wires going to it or i would have linked them together

 

[Billy Bob Bob]

and you have checked other things like thermistor, comb door off,re airswitch blocked plate heat?by f;ow switch do you mean dhw flow switch?or main?if dhw does the switch glow red when working?

 

[wnjswozo]

nasty boilers i would give a wide berth

 

[Billy Bob Bob]

nasty boilers i would give a wide berth

oh yes b+q crap owned by vailent/glowworm

 

[Mark raig]

Hi Mate yes the red led comes on when the boiler works otherwise it fails to light the ch side works fine. I have a feeling that the cold water pressure is lowish but Ive checked the flow rate with a weir gauge and it was well over minimum requirements. I meant the dhw flow switch sensor on the right hand side of the combi

 

[Billy Bob Bob]

Hi Mate yes the red led comes on when the boiler works otherwise it fails to light the ch side works fine. I have a feeling that the cold water pressure is lowish but Ive checked the flow rate with a weir gauge and it was well over minimum requirements. I meant the dhw flow switch sensor on the right hand side of the combi

if the dhw switch is constantly glowing red when the dhw is running rule it out,its not the problem,re-look at airswitch,tubing,venturies, then check dhw thermistor,if this draws a blank plate heat also when you run the dhw does flow pipe get v hot? you may need heating off to check if this is the case flow group/diverter is knackered or plate heat is blocked check all of these before condemning the pcb

 

[wnjswozo]

love to know how much pcb would cost,i bet its half the price of the boiler

 

[Mark raig]

120 quid just priced one

The problem is that sometimes it works sometimes it dosnt when it does work the light comes on when it dosnt work the light stops off it dosnt mater if the boiler is set to ch mode or dhw only it wouldnt be so bad if it was constant the fans noisy as well and it needs a new PRV as well triewd to tell the customer a new boliler woud be a better option there over 300 quids worth of parts before you start

 

[fireblade]

The hot water switch is a turbine type with a hall effect pickup magnet so hard to test i had to go out to one when there was a lot of water demand on the street the turbine would not move after 6.30 hot water was fine again.

 

[Mark raig]

Hello just been out to the boiler again the system pressure was low as i topped it up the hot water tap was opened and the pressure started to drop again from reading various other threads it looks like the expansion vessel could be knackered as well then dosnt it?
cheers in advance for your help
Mark

 

[Gasboy]

PCB heatline vizo 24 £234.70 @hrpc not cheap

Get rid of it nothing but trouble

 

[dublin plumber]

asked to look at one recently , it worked for an hour a day then switched off , found it to be a blocked heat exchanger , customer bought another boiler !