Quite a Poser

[corgiman]

Went out this morning to a noisey system

is an Ideal Icos, grunfos pump and ACL lifestyle three port and no TRV's

when the hot water only is under demand, no noise
when the CH only is under demand, no noise
when both are on the noise is fairly loud (a vibrating type) for about twenty minutes then it goes

Noise defo not coming from boiler (surprisingly)
I thought it sounded like it was coming from the valve so I changed it (i know I werent 100% sure Agile but thought it was worth a pop as it was costing Mr Matey Nowt for my time etc) and the noise is still there?

so I whacked in a new pump and same as

Any Ideas as I am fummoxed, I cant explain why it only happens in mid postion?

Cheers Boys

 

[Agile]

These kind of problems can be difficult to fix.

I would start by listening to each part with my mechanical stethescope. That would probably identify what it is.

There are many unlikely causes but my first guess is that there may be some air trapped in part of the system and this is setting up a water coluum resonance under certain temperature or expansion conditions!

Let us know what you find it is!

Tony

 

[Alfredo]

Does changing pump speed have any effect?

Alfredo

 

[ChrisR]

Um, trv's, lockshield on HW circuit, loose pipe?
Might be interesting to adjust a pump valve to see...

 

[corgiman]

Um, trv's, lockshield on HW circuit, loose pipe?
Might be interesting to adjust a pump valve to see...

I have checked for looses pipes chris, but the noise is more a grinding motor type, I will try the pump valves, but why would they only do it in mid pos???

Does changing pump speed have any effect?

Alfredo

No at all al, I did try that and it still does it

These kind of problems can be difficult to fix.

I would start by listening to each part with my mechanical stethescope. That would probably identify what it is.

There are many unlikely causes but my first guess is that there may be some air trapped in part of the system and this is setting up a water coluum resonance under certain temperature or expansion conditions!

Let us know what you find it is!

Tony

Thats an understatment tony, their a booger to fix

Good idea on the air though, but, again why wouldnt it happy in, say, CH only?

 

[Alfredo]

Showing my ignorance..is the system open vent or sealed? If open..could it be blocked cold feed starving system of water, but enough to run each system CH/HW independently..its a long shot i know

Alfredo

 

[corgiman]

its open vented but we installed the ch and all primaries were up graded and system was flush to within an inch of its life

I am back there next week and will keep you lads posted

 

[doitall]

If you want to email a drawing I could probably tell you what it is.

 

[corgiman]

of what?

 

[bripl]

have had probs with acl diverter in the past now only fit honeywell.
grinding noise would suggest a pump problem bit of sh1te dropping in the impellors?,you say the sys was flushed using what chemicals?if you mixed chems is their a reaction going on causing cavitation in the pump due to the restriction of mid position valve[bubbles forming]had this before and am now nearly bald good luck and let us know the outcome

 

[doitall]

of what?

The pipe work between the boiler through to the valve and the cylinder.

Make and type of cylinder would be handy as well.

Model of icos is.

 

[corgiman]

Ablion Super duty and an Icos he24 (not the m30100 series the newer one)

I will try but I am to drawing what van gogh is to electrics

 

[doitall]

Ablion Super duty and an Icos he24 (not the m30100 series the newer one)

I will try but I am to drawing what van gogh is to electrics

Any scribble will do as I can tidy it up.

Do you know the GC number 41.397.82 or 41.397.85.

 

[ChrisR]

If pump speed doesn't alter it, flow-related things all seem to be out of the question.

A thought - if the actuator is like many others there's a diode in the supply to the motor when it's stalled in mid pos. That can make the motor make a noise. It would disappear the instant you "satisfiy" the HW and the motor starts moving to CH only, whereas if it's a water-speed related noise, the noise would fade away as the valve moves.
I've used all sorts for mechanical stethoscopes - big screwdriver, hammer, hockey stick, bit of pipe...

 

[dan the man]

like mystery threads like this

It will turn out to be next doors headboard