Ravenheat RSF84 vibration problem

[wizbongre]

That was my very first thought. I just need to confirm if the fan is under extra load when DHW is in demand compared to CH. Otherwise I can't understand why it doesn't happen during CH only.

 

[lifesagasman]

higher fan load/speed and much higher temperature makes the bearings groan (on mine)

you can't rule out possibly the pump bearings are shot. with the front cover off hold a long screwdriver to the pump body with the (blunt--H&S) end tight to your ear. you can hear the pump bearings

 

[wizbongre]

Brilliant thanks - that at least gives me something specific to look at and rule out.

 

[lifesagasman]

higher fan load/speed and much higher temperature makes the bearings groan (on mine)

you can't rule out possibly the pump bearings are shot. with the front cover off hold a long screwdriver to the pump body with the (blunt--H&S) end tight to your ear. you can hear the pump bearings

 

[Agile]

fan bearings are a strong contender

Not to me!

The fan runs at a constant speed ( if I am thinking of the right model ) amd is running at the same speed for hot water and heating.

If I am not thinking of the right model then the fan is modulated and runs faster on higher power which is required for hot water. But the variable speed fans seem to be better built and worn bearings is very unusual on them.

Tony

 

[lifesagasman]

i'm only saying what i hear on my own boiler (9 years old and only 1 pcb)
fans don't last forever

 

[Agile]

If there is only one PCB then the fan will ( I think ) only run at a single constant speed.

Whilst different power outputs will have a very slight effect on the boiler noise from the fan although the noise of the boiler will be louder from the greater volume of gas being burnt.

Single speed fans do often wear their bearings and become noisy. Not a big problem on NON-pilot light Ravenheat boilers though where they only run when the boiler is operating.

Sorry if I may sound a little vague about these boilers but Ravenheat have produced several boilers under the same general types with significantly differing internal configurations.

Tony

 

[lifesagasman]

i'm only saying what i hear on my own boiler (9 years old and only 1 pcb)
fans don't last forever

read - only 1 pcb replaced in 9 years -

the OP is looking for the cause of a mechanical vibration

 

[Agile]

I can only read what the words say!

Are you now saying your boiler has TWO pcbs in it? That would mean its a modulating fan and not a constant speed.

Tony

 

[lifesagasman]

i'm supposed to be revising for an assessment tomorrow....

 

[wizbongre]

Thanks for he further info. Been working away all week so not had a chance to do any testing yet.

Will look into pump bearings and see if I can confirm if it could be fan bearings too.