Vaillant Ecotec boiler losing pressure intermittently

hill37

Hi.
In June,i had to replace my valiant boiler with a new one(no new radiators),also valiant.After a lot of research,i found a good engineer who installed the boiler fuss free.It cost me a lot of money which i had to lend off my credit union.As it was summer,i didn't have the heating on.Recently,i popped the heating on and noticed a leak from my kitchen radiator which is only 2 years old.
Now i know a new boiler can find leaks out.So i phoned the installer who came and said the valve on the radiator was shorn off.He promised to come back and replace it.He never came back.Now im looking at having to get  someone else in to fix this problem.Anyone else ever had this problem? 

Jeepers_Creepers

Hi Hill.

Assuming that the new boiler is the same type (vented, system or combi) as the old one, then it has nothing to do with your leak.

Due to the fact that the leak only started once your turned on the CH, I'm guessing it's down to the leaking part of the valve expanding with the hot water and leaking due to this.

It's disappointing he hasn't come out yet to sort it. I suspect he is busy with larger jobs - better money-makers - or just too busy to fit in what is a small, but potentially time-consuming, job. If he needs to replace the rad valve, then that means either freezing the pipe or else draining down - a hassle for such a small thing. 

He might also be wondering whether you're going to expect this repair to be carried out under some sort of warranty or obligation? If so, he shouldn't - this is a separate issue, and will need paying for. Having said that, it would be nice if he charged you a lower rate since you've been a good customer. 

Putting all that aside, could you post a photo of the leaking valve - a good close-up pic - and perhaps there's a way of stopping the leak without replacement. 

hill37

Thanks so much for taking the time to reply.
When he first had a look and said it was the valve,he said he would either have to isolate the radiator(with some machine which he said he didnt have with him) or drain the system.This was a Friday night and said he'd be back first thing Monday morning..
Yes,i think you are right.Obviously i would have paid to get the leak sorted but he told me he had a lot on,moving his company into whole bathroom renovations etc. So i think solving one leak which may take an hr or so(whole replacement combi only took 3 +hrs),was not a priority.I just dont know how much this is going to cost me now .
Anyway,my moan over.Here's a pic of the valve. 

Jeepers_Creepers

The machine would have been a pipe freezer, most likely.

Can you point to where exactly the leak is coming from? If necessary, you can remove the white TRV control head by unscrewing that top chrome collar anti-clockwise. We might get away with a wee tweak of the nut underneath.

hill37

He said the valve was shorn off though Just inspected it best i could..Its definitely coming from the top screw immediately under the TRV and the leak seems to be getting worse or it could be just that i have the heating on longer.I wouldn't mind but that's a fairly new radiator and connections.
Wouldn't that have been a lot quicker then to have used the pipe freeze?
I really feel like writing a bad review about him.Not sure though as i still have a 1st year service included in the fee i paid.
Also,if i turned off the TRV,would that temporarily stop the drip until i could sort it?

Jeepers_Creepers

Yes, if you turn that TRV off completely and also the 'lockshield' valve on the other end, then - in theory - the drips will stop shortly afterwards. However, TRVs are notorious for letting by a tiny trickle even when 'off', and this would be enough to supply that drip, so don't be surprised if it carries on. But, definitely worth a try :-)

(If you do shut off the lockshield, then count the number of turns and part-turns it takes so's you can return it to the exact same point after all this is over.)

Come on - take your head off - you know you want to. Open the TRV fully to take the pressure off the valve spindle and unscrew that chrome collar anti-clockwise. Lift off the head and post a photo of what you see. I'm assuming these valves have gland nuts just like 'normal' valves, in which case you may be able to fix this drip with an eighth-turn tightening of the nut under the spindle. But don't try that until you show us what's under your head...

(Do you have WD40 type spray, or - ideally - silicone spray or grease?)