Help Please with Ravenheat CSI 85

[bob the plumber]

hoping one of you more experienced lads can help! My breakdown knowledge is basic but im trying to help a friend out whos short on a few pennies.

I am GSR

Ravenheat CSI 85 does not fire on demand for hw and ch

pressure is fine
power is fine
gas present

engineer light turns on when there is demand or ch/hw

pump runs
no 230v to fan?

got back to the overheat stat which i believe is causing the problem
I switched the cables on the overheat stat which made the fan run so i know the fan works
however as daft as this sounds am i correct in saying that the air pressure switch will only operate when the fan operates?
how do i check that the pressure switch is operating as it should
and how do i know for a fact that the overheat stat is deffo to blame?

thanks for your patience and time, they dont teach you so much breakdown stuff at college and all i do all day long is install after install with oil, gas boilers and bathrooms so i dont get much chance to get involved in the breakdwn side and im just wanting to learn, good opportunity on my friends boiler 🙂

thanks

bob

 

[JAH HEATING]

you can make the air prerssure switch by attacking a u-guage tube and start to suck or blow on it mate

 

[bob the plumber]

jah, cheers, i did that and it clicks so i guess its working then? i doubt myself to much 🙂 how about the overheat stat, live neutral and black cable?

 

[JAH HEATING]

you could link your overheat stat out with a bit of wire ?

so you're not getting nothing at your fan ?

you need the combustion cover on these boilers pretty sealed to fire by the way mate, don't just leave it off

 

[mcniven]

no 240v to fan ans aps works? could be pcb??

 

[bob the plumber]

by not putting the cover on whilst testing i take it then that would in effect disrupt the air pressure switch?

 

[Billy Bob Bob]

on the ravenheap you will not get to run with the combustion door off dont suck or blow into the aps you will kill it bob if you have taken direct mains to the fan i would be looking for 240v leaving the pcb to the fan its at this point you really need to be conversant with a multimeter if your not then i can talk you
through the basics

 

[bob the plumber]

no 240v to fan ans aps works? could be pcb??

i bloody hope not 🙁 its me paying for it, my friend is skint and im helping her out, i swapped the cable around at the back of overheat stat to temp bypass it fan then worked but solenoid gas valve didnt. im putting it down to the overheat but if you can figure out in your head what i did lol you might be able to confirm it to me. 🙂 cheers

 

[JAH HEATING]

you've linked the the stat out now and the fan is running ?

Is combustion cover on tight ?

Is it trying to spark at burner ?

You say you're getting gas past your Gas Valve ?

Ignition Board on Gas Valve if not sparking, exspensive mate if I remember rightly

 

[bob the plumber]

what do you suggest gasman?

 

[bob the plumber]

when i switch the overheat wires, i get power to fan, when i blow down aps and seal tube with fan running i get ignition which means if i put the bloomin lid on, it would probably work?

 

[JAH HEATING]

when i switch the overheat wires, i get power to fan, when i blow down aps and seal tube with fan running i get ignition which means if i put the bloomin lid on, it would probably work?

Put your liad on it and make the switch, sounds like you're air pressure to me

 

[JAH HEATING]

typo - cover rather

 

[bob the plumber]

ill have another look tomorrow morning, see if my fresh more knowledgable haed makes a diffenerence 🙂 thanks

 

[bob the plumber]

it was the overheat stat, i got it right. got the part today and replaced, quite chuffed with myself...thanks all

 

[aladin]

here we go our old friend ravenheat. i posted awhile back csi 85 hot water cuts out c/h fine i fitted new hex as it was slightly scaled up new h/w ntc still cuts out after a short while (couldnt get through to tech) any ideas would be realy apreciated