Radiators have a loud vibrate and stay on past timer

[k0r54]

Hi,

We have just purchased a property that is an x-repo and been sitting for around 2 years. We got the boiler started which is a new (2.5 years old) and it provides instant hot water (which appears to be working) and then central heating on a timer. We are currently having two issues with it.

First is we get a very loud vibrating noise (kind of like drilling into a wall) occasionaly coming from a few of the radiators. If the noise comes it comes from the several radiators at the same time. If I then alter the TRV on one of the radiators it stops the noise completely from all the radiators.

Second problem is that the radiators all get nice and warm but when the timer is then switching the radiators off they actually end up staying on. Some go luke warm and other stay very hot but the timer is actually off.

Additional Info:
I have an Ideal boiler and then on top of that have a timer for both hot water and central heater (assuming the hot water is being ignored because it is supposed to be instant hot water). We also have a thermastat on the wall.

any advice or help would be great

k0r54

 

[stem]

TRV's can make the noise you describe if they are fitted the wrong way around. (look to see if they have an arrow on them showing direction of flow) or the system is incorrectly balanced so that pressure is too high.

With regard to them not going cool, radiators cool from the bottom upwards and it can be quite some time before the top cools after the boiler goes off. Does the boiler keep firing after the timer should have switched off?

Some combi boilers have a timer for the water, so that when the boiler isn't heating the radiators and is cold, a pre-heat operates occasionally to keep it warm in case hot water is needed. This facility isn't necessary at night, or when you're not home and would waste energy, so a time switch can be used to turn this feature off. Maybe someone who knows your boiler type more intimately will advise.

 

[k0r54]

Hi Stem,

Ok I have switched my heating on and on every radiator the trv is attached to the pipe that heats up second.

Once the radiators get hot I will switch off timer and post back about if they stay hot or not.

What are your thoughts on the trv's?

Thanks
k0r54

 

[k0r54]

Ok,

The heating just seems to be on all the time. The timer says it is off and I have looked at the boiler which has either d (domestic water) and c (central heating), everytime I hear the boiler go I take a look and not once have I seen C and yet the radiators are on?

Hopefully this and the other issue with the noise is easily solvable.

Thanks
k0r54

 

[tininho]

Is the boiler an Ideal Isar???

If so, sounds like the divertor valve is passing to the CH.... This boiler comes with a pre-heat, and if the div/valve passes it will continue to fire in DHW to try and satisfy the HW pre-heat, giving the impression that there is a demand for CH when clearly there isn't....

Re the TRV's.... What make are they.... some are bi-directional (can be on the flow or return), some are not....

Martin

 

[k0r54]

Hi yes it is a Ideal Isar.

If that was the case and the valve was passing it to CH would that mean that I would NOT have hot water because the HW seems to be working fine. If not, where do I find this valve? Any Ideas what they look like?

The TRV's are Landis & Gyr and they look quite old. I have tried to look for arrows on there but I cannot seem to find anything.

All your help is appreciated.

Thanks
k0r54

 

[tininho]

Hi,

To be honest, yea, you usually would notice a "cooling" of the HW. This cooling is some times marginal however, so you may not notice any small drop (though this is admittedly unusual in my experience).....

For me, the relevant point is the fact that the appliance continually fires up in D (Domestic) and with no demand, CH seemimgly comes on..... and this quite def points to the div/valve....

The valve is located at the bottom left had side (just under the outer case).... It will either be grey in colour or Red and Black..... The visible part is the actuator, which is clipped onto the div/valve cartridge..... Removal process depends on which you have.....

Difficult to correctly diagnose without seeing it, however it sounds like the div/valve cartridge needs replaced (Try greasing the seal, but this rarely helps......). The actuator sounds not to be faulty, but I seem to remember the full thing comes as a kit anyway......

Hope this helps

Martin

 

[k0r54]

Hi,

Thanks for the advice. I called a local firm and they want £105 for it.

I have found these two things on ebay so am not sure which one i actually need. What would you advise?

http://cgi.ebay.co.uk/Ideal-Isar-EV...arden_Hearing_Cooling_Air?hash=item1c044bb0d7

http://cgi.ebay.co.uk/Ideal-Isar-HE...arden_Hearing_Cooling_Air?hash=item20afb01d17

and this one has a different part number but this is the part number they guy said on the phone

http://cgi.ebay.co.uk/Ideal-Isar-Di...arden_Hearing_Cooling_Air?hash=item3efd2b89b8

Thanks
k0r54

 

[k0r54]

Ok,

I have got home and taken the front of the boiler off.

I have found the div valve and it is gray with a red top. (Square type thing).

How do I take the div valve out? I undid a torque screw underneith and water started to pour from the boiler so I very quickly did it back up.

Any tips would be great.

Thanks
k0r54

 

[tininho]

Could you post a pic of the div valve??? Just want to be sure which one you have, as each comes out differently....

Martin

 

[tininho]

Is it this one???

http://cgi.ebay.co.uk/Ideal-Isar-HE...arden_Hearing_Cooling_Air?hash=item20afb01d17

Martin

 

[tininho]

This is the one with the part number you were given.... This is what will be in the box on the last link you gave....

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?VISuperSize&item=320495289723

Martin

 

[k0r54]

Hey,

Ok, I have drained the boiler which appears to have works and I removed the div valve successfully.

I have found a local place that sells the valve on its own for £36 which I am happy to buy.

Please see the pics I have attached and I assume it is the little gold bit that is the broken bit. With the boiler drained does it drain the radiators etc?

Is there anything I should do whilst the system is drained. (Any treatment or anything).

Assuming the part I pick up tomorrow morning matches correctly should it just all fit back in and work?

Anything I should look out for?

Thanks very much for your ongoing help with this.

Thanks
k0r54 View media item 20224 View media item 20225 View media item 20224

 

[tininho]

Congrats... Exactly the correct component... The brass section is the cartridge, which I would recomend replacing..... Just re-assemble in reverse order..... Would be worth our while to pick up a tube of aquasil sillicone grease, just to lubricate the orings before re-assembling....

With regards to the rads needing bled.... Depends how you drained it.... Did you open the outside drain? or just the drain point under the boiler.... If you drained it from the main drain, you may have to bleed the rads....

Martin

 

[k0r54]

Hi,

Ok the brass bit has been fitted and the original actuator has gone back on. I opened the shut of valves just under the boiler and I put about 17psi preausre back into the boiler.

I have given it about 5 min and have run the hot water. The water gets hot after about 5 seconds and the holds that heat for about 3-5 seconds longer then it gets luke warm and just stay luke warm?

Radiators have heated up fine but obviously cannot test until I know they have cooled down.

Any ideas about why the hot water will not stay hot?

Added:: Looks like the radiators are still not cooling down although it has only been about 15 min.

Perhaps it is not the right part. What else could it be?

Thanks
k0r54