ravenheat keeps stopping

[marko01]

Hi everyone. new post so bear with me. glad to have found this forum.

I have (inherited) a ravenheat rsf 820. This morning it was firing up and then stopping, then firing up(10mins) and stopping. Then it fired normally for an hour before stopping again.

When it fires i can hear the fan spinning and it sparks OK. The burner lights without a prob. I took the cover off to have a look. Ran the hot tap and also had heating on. Couldnt hear the fan and no sparks. Switched it off at the panel and on - fan runs, sparks, lights and runs then 2 mins later goes out.

I notice a little control board in the bottom left. Looks like on it is a little relay and it was sparking. I used an electricians screwdriver and gently tapped the wires behind and the boiler lit. Ok for an hour then it goes out again.

Is that little board the problem here and how is it fixed.

 

[marko01]

nothing happening now. no hot water or heating

 

[gasmick2]

hi it does sound like the board if the small relay is sparking but they do flash a bit as they are switching 240v every time it fires up i would look at the air pressure switch pipes as they tend to go hard and crack and then it will keep pullin in a bit of air and drops the air pressure switch out so causing the boiler to go out mind you its a corgi engineers job to remove the front cover to the combustion chamber
other things to check is the ventura pipe that the pos pipe fits to from the a p s sometimes they get partially blocked
there the things i would check first if it was me looking at it
i used to be an out of warranty engineer for ravenheat before i was forced to retire owing to ill health and have repaired loads of 820 s
if the pipes are ok then its the board it cannot be repaired only replaced
only use a genuine ravenheat one there are some after market ones
but like all things its not genuine and could cause a fire if it goes wrong

 

[Slugbabydotcom]

Tell us what isn't working that made you start pulling it apart

Are your radiators hot and do you get hot water?

 

[marko01]

When it was working both heating and water were fine. It just kept cutting out. Then it would start up again so i had a look to check. Thats when i noticed the board ??relay sparking. Just tapping the wires behind resulted in the boiler firing up again ---until now.

 

[Slugbabydotcom]

Those PCB's do go wrong now and then. Check the connections and if you feel able take it out and have a good look at both sides of it. Dry joints and dodgy relays usually turn black when theres a fault. Quite often they smell a bit too.
Check fan resistance is in region of 45-55 ohms. You don't want to take another PCB out!

 

[marko01]

Those PCB's do go wrong now and then. Check the connections and if you feel able take it out and have a good look at both sides of it. Dry joints and dodgy relays usually turn black when theres a fault. Quite often they smell a bit too.
Check fan resistance is in region of 45-55 ohms. You don't want to take another PCB out!

How do you check fan resistance on these. I took a quick look and the fan seems to have 3 wires plus an earth??

Mark

 

[Agile]

You take your multimeter and measure the resistance betwen the windings.

You then scratch your head and think for an hour or two and then think that it may have two windings, one for full speed and one for slow speed to clear the products of combustion from the pilot light.

Of course, I would be saying that you should not even be opening up the combustion chamber if you are not CORGI or equally competent to work in your own home.

Tony

 

[marko01]

I realised that Tony once i took the cover off and saw the burner. Why don't manufacturers stick labels with " Do not remove unless CORGI registered" on them, or seal them like on gas meters.

I put the cover straight back on, but am interested in how a fan would be tested. But i now understand the 3 wires as it has 2 windings. Therefore i assume it spins slowly to remove waste from the pilot then spins faster when fully alight.

 

[Agile]

Therefore i assume it spins slowly to remove waste from the pilot then spins faster when fully alight.

Well almost !

The fan is speeded up just BEFORE the burner is lit.

In any case I have no reason to suspect there is anything wrong with your fan!

Tony

 

[marko01]

A corgi guy is coming tomorrow afternoon. He is certain its the board so is bringing a pcb

 

[Agile]

Probably is but dont pay him if its not!

Tony

 

[ChrisR]

Pay him for a DIAGNOSIS though - that's what Tony charges for!