Ideal Response 120 safety valve

[titusyouclown]

I've had the above model boiler in my house for a number of years, and last winter I noticed that after every use of the central heating the system would completely depressurise. For one reason or another I didn't get round to looking at it, but this year its become an annoyance so I've investigated. After talking to friends in the know they told me to look for a red safety valve, as it may be there's leak from it (I've checked every joint in the entire house and I'm certain there are no leaks). Last night I made a discovery - I found the valve and noticed that if you turned it one way, it drained the system (I heard the water splash onto the path outside) so I concluded that while cooling after use, the water is leaking out past the safety valve. To prove that fact I put a dry cloth under the outgoing pipe to see what happened - what actually happens it after about 15 minutes of use, the pressure rises to about 3.5 bar and the valve opens, emptying a good proportion of the water out. Once switched off, the remaining water slowly drips from the system past the safety valve. Now, obviously a safety valve is a necessity, but is there any way I can increase its resistance to stop this happening? Its in a awkward place to get at so I can't tell if its adjustable - all I know is its a red plastic twistable cap which opens the valve if twisted anti-clockwise. Any ideas?

 

[Strachan]

Replace it. You can`t alter the resistance, once it`s gone it`s gone!

 

[sm1thson]

theres a bit more to it! -your system shouldnt be going to 3.5 bar -address this first! (read the faq's / the wiki reguarding the expansion vesel) once that is sorted the pressure should stay more stable will probably find the valve still drips (as they tend to once they have opened) so then replace it.

 

[ChrisR]

They're really easy to replace.
Once you've done a couple of dozen and aquired the right tools...

Check the bottom edge of the expansion vessel for signs of water stains too - they leak.

 

[titusyouclown]

Having taken the front off and had a look round I'm a bit more savvy with what goes where, but what does the expansion vessel look like, and whereabouts should it be?

 

[ChrisR]

Hmm, time to get the manual - on the Ideal site still I think. EV is on the right, going top to bottom. It's reddish orange.Pumping up valve is under a plate on the top.
Lower edge is just visible - behind the gas valve.
To check its pressure you need to drain the boiler. Drain cock is underneath on the right, grey knob, with metal round it as though specifically to stop you getting to it. Takes an age to drain...

 

[Rob]

to get to the vessel you need to remove the plate on top of the boiler. 2screws front one rear. this WILL need charging. very common.

and personally id be a bit persistant and get the valve to re-seat. they are very difficult to change unless you can stand underneath the boiler.

 

[ChrisR]

You can get the exp vessel out to the right too, rhs comes off. Total 17 screws iirc! Only do it if you're sure it's leaking though.

The whole PRV's take about a minute with the right tools! I think the first one took me nearly an hour Takes a while to drain though...

 

[Rob]

yes the gurgling seems to last forever! TBH only faults ive really seen is exp. vessel related and LWPS.

Luckily i think most have taken out by now, must be atleast 5 yrs old. lol

 

[titusyouclown]

I drained some of it last night and left it overnight, and when I cam home tonight its working again! The pressure is staying at 2 bar constantly so I think I'm on the right lines. Do you think its worth fully draining the EV?

 

[scatmanjohn]

I drained some of it last night and left it overnight, and when I cam home tonight its working again! The pressure is staying at 2 bar constantly so I think I'm on the right lines. Do you think its worth fully draining the EV?

2 bar is too high. It should be 1 bar.

BTW...start saving up for your new heat exchanger or better still, new boiler.

 

[ChrisR]

The heat exchangers are not available from Ideal any more. What a shame at £400 a go.

 

[scatmanjohn]

The heat exchangers are not available from Ideal any more. What a shame at £400 a go.

How do they get away with it?

Don't they have to supply parts for a set period of time?

 

[corgiman]

scat is right, cut your loses and get a new one

 

[titusyouclown]

I completely drained the expansion valve this morning, repressurised the system and its not working flawlessly - doesn't rise above 1 bar now and stays pressurised after use.

Thanks to everyone for your help with this.