rattling and vibration near radiators

[spenkyg]

Hi,

I am looking for some advice assistance with a reacurring problem that i'm having in my new flat.

I have a raven combi boiler supplying 6 radiators and a towel rail.

I am getting a rattling and vibration near radiators. This happens fairly regularly but the volume/intensity of the noise and vibration varies as does the location (sometimes spanning the plumbiong between two radiators. This problem also seems to happen either at heating start up (in the morning) or after the system has been running for a couple of hours (in the evening).

A temporary soloution is readjusting the radiator flow valves, though this only solves the problem for an hour or so and then the problem moves.

All the radiators have been thoroughly bleed and I have been informed by the person below me that it has always had this issue since being fitted a few years ago.

I seem to have solved it (fingers crossed!) by reducing the thermostat on the boiler to its near minimum position, but......This leaves me with:-

luke warm radiators = unhappy girlfriend.
and luke warm water = unhappy me.

From what I have read on the site it may be that the flow rate on the pump may be set to high so I am thinking about playing with this but would appreciate input from someone that knows more about these things than me....

So, what can I do?

Thanks for taking the time to read this and if there is any pertinant info missing, ask and I will provide it....

Thanks again!

 

[gas4you]

By vibration, would you mean a banging sound, a bit like a pneumatic drill?

If so it could be the TRV's are on the wrong way round for the flow.

How many arrows are on the valve body?

If only 1 check the water flow is going in the direction of this arrow (see which pipe gets hot first = flow)

 

[spenkyg]

Hi there,

thanks for getting back to me....

Sound wise yes very much like a drill (aparently more so from the flat below!)

The TRV's all have two arrows on each pointing to the pipe to which they are connected to...some have C on one arrow?

It could maybe be the TRVs though as at least one doesn't properly work and I have isoplated that rad from the system by closing the manual valve on the other end of the rad.

I have just checked and the pump is set to the max flow (ie III position). Is changing this an option?

Thanks

 

[bengasman]

noise could be a dozen things, hard to say.
pump got to be at 3, that is not hard

 

[spenkyg]

O, also I have other radiators not on but just by positioning the TRV's to off...

Though I have been assuming that this doesn't have an effect on the system OA?

 

[gas4you]

The TRV's all have two arrows on each pointing to the pipe to which they are connected to...some have C on one arrow?

If the 2 arrows on the trv's are both pointing to the pipe I think I know which ones you mean, but cannot recollect the make right now.

It sounds as though yours are the wrong way round if they are what I am thinking of.

My previous post of 2 arrows actually meant the 2 arrows were on seperate parts of the valve body, one pointing at the pipe, the other pointing at the radiator.

As a total guess, I would say that the ravenheat replaced another boiler in the past and the installer swapped the flow and returns around.

Hence why the flat beneath says it has done it for ages.

 

[spenkyg]

Sorry I may have miss lead you.
There are to arrows total:

one pointing left to the raditor and one pointing down to the pipe. The trv is on the top.

Does this tally withyour guess that they have been placed the wrong way around?

IF that is the case is this something that I can do by just draining the system and rearranging the valves?

Cheers for the input so far

 

[gas4you]

No, they seem modern 2 way valves.

What make are they?

I have had quite a lot of Honeywell valves bang as if the flow is wrong, but just turned out to be faulty valves.

 

[spenkyg]

Hi Dave,

The TRV's don't have a name but they do have a symbol on the top of a low case 'h' with a flame coming out the top....I'm assuming that these are honeywell!

Would only a few valves being faulty cause a roaming fault like I have or is it likley most if not all have failed?

I have read about balancing is this worth while before looking at TRV replacment?

I have also read about an auto by-pass valve is this worth considering?

I am currently investigating the flow direction and will update the findings from that if its valuable.

 

[spenkyg]

Flow direction on four of the radiators (I have another couple that i haven't checked)

2 off flow going into the rad on the TRV side

and 2 off flow going into the non-TRV side!

I'm guessing that this may have something to do with my problem???