Valve settings

Cap066

I've got the 4 valves under my logic  combi espi 35 boiler. The 2 blue ones which are used to top up the pressure....these are definitely off. It's the 2 black ones that I'm not sure about. They have been fiddled with and now I'm not sure if the black valves are on or off. There is one on the left by itself and one on the right which is in line with the 2 blue top up valves.
 I have found a video where vertical  is the OFF position but I'm not sure.
 Is there a way to check by testing the heating or hot tap water flow?  At the moment I'm reluctant to do anything in case I damage the boiler

ThisIsWeird

Hi. A photo would help, tho' I can check online when I go on my PC.
They sound like the isolating valves on the Flow and Return pipes to your radiators, your 'CH'. Are they on the larger 22mm pipes?
Usually, having the valve's lever in-line with the pipe direction means 'on'. Tbh, if one of these valves is 'off', then your CH simply wouldn't be working.
Is there any reason why they might have been adjusted? Have you had anyone out looking at/servicing your boiler? Is there something not 'working' with your system that makes you suspect these valves?

ThisIsWeird

Yes, these are the F and R pipes to your radiators.

"Open 'vertical' position' for the F and R valves". 

Bottom line - both will be either need to be fully vertical or fully horizontal for open. In one position, your rads won't heat, and your boiler will almost certainly return an immediate 'restricted flow' error, and lock out.

https://gas101.co.uk/ideal_boiler_manuals/ideal-logic-combi-esp1-35-4734923/

Read the 'filling system' section on page 31.

Cap066

ThisIsWeird said:

Yes, these are the F and R pipes to your radiators.

Thanks. That helps a lot. So those pipes/valves are nothing to do with  hot water to the  taps?  I did wonder why I was getting hot water whatever position the black valves were in!  

ThisIsWeird

Cap066 said:

ThisIsWeird said:

Yes, these are the F and R pipes to your radiators.

Thanks. That helps a lot. So those pipes/valves are nothing to do with  hot water to the  taps?  I did wonder why I was getting hot water whatever position the black valves were in!  

Ha-ha! No, completely separate. There will be a separate (Blue) valve on a 15mm pipe which is the cold mains supply to the boiler. If you close that one, then your hot water (DHW) will shut off. You can see it in that same diagram.

Do you actually have an issue you are concerned about, or is it all working as it should?

In essence, all these valves should be either fully on or - when required for testing, etc - fully off. Not part-way.

Cap066

ThisIsWeird said:

Cap066 said:

ThisIsWeird said:

Yes, these are the F and R pipes to your radiators.

Thanks. That helps a lot. So those pipes/valves are nothing to do with  hot water to the  taps?  I did wonder why I was getting hot water whatever position the black valves were in!  

Ha-ha! No, completely separate. There will be a separate (Blue) valve on a 15mm pipe which is the cold mains supply to the boiler. If you close that one, then your hot water (DHW) will shut off. You can see it in that same diagram.

Do you actually have an issue you are concerned about, or is it all working as it should?

In essence, all these valves should be either fully on or - when required for testing, etc - fully off. Not part-way.

I have had a problem with falling pressure on the boiler for months now. I can't find a leak anywhere on my heating system. I had a plumber/gasman rule out the expansion vessel. He advised me to pull out the plastic tube under the boiler and insert an open tube and leave it overnight. If there is any water in the morning  it would confirm another internal boiler part would be responsible ( can't remember it's name but I know it's expensive! ) 
The reason for the confusion over the black valves was that I started the process the other night and got distracted. When I returned to the boiler I was confused by the vertical position of these and wasn't sure I had left them open or closed! It turned out vertical was open.  I haven't done the pipe check yet due to shift work and the boiler still being used at night. I'll get round to it soon 

ThisIsWeird

Ah, I see.

That plastic pipe will be the 'condensate' pipe. When the boiler is actually running, it produces 'condensate', and this will exit via that pipe in 'glugs'. When the boiler is off, the 'glugs' should soon stop. If water continues to come out, then that suggests the main heat exchanger (also called the 'engine' or 'MainX') is cracked, which is usually the death knell for a boiler.

Make and model of boiler, and how old is it?

Does that plastic pipe head outside? If so, you could just place a container under it overnight, and hope it doesn't rain...

I presume - since he ruled out the expansion vessel - that there definitely isn't any water coming out the smaller, 15mm, copper pipe outside?

One of the simplest first checks - now that you are familiar with these valves... - is to shut off the boiler, making sure it cannot come back on (eg, turn off the power to it). Pressurise it to a noted level - say 1.5bar (take a photo) - and then fully close the two black valves, the Flow and Return. This will isolate the boiler from the radiators. Leave it for at least overnight. If the pressure still drops, the leak must be from within the boiler. If the pressure does not fall, then keep an eye on the pressure gauge as you reopen the valves. If it then drops, the leak is in your radiator/pipework system.

This all depends on how quickly the pressure is dropping. If it's dead slow, then you may struggle to ID this with just an overnight test.

Cap066

ThisIsWeird said:

Ah, I see.

That plastic pipe will be the 'condensate' pipe. When the boiler is actually running, it produces 'condensate', and this will exit via that pipe in 'glugs'. When the boiler is off, the 'glugs' should soon stop. If water continues to come out, then that suggests the main heat exchanger (also called the 'engine' or 'MainX') is cracked, which is usually the death knell for a boiler.

Make and model of boiler, and how old is it?

Does that plastic pipe head outside? If so, you could just place a container under it overnight, and hope it doesn't rain...

I presume - since he ruled out the expansion vessel - that there definitely isn't any water coming out the smaller, 15mm, copper pipe outside?

One of the simplest first checks - now that you are familiar with these valves... - is to shut off the boiler, making sure it cannot come back on (eg, turn off the power to it). Pressurise it to a noted level - say 1.5bar (take a photo) - and then fully close the two black valves, the Flow and Return. This will isolate the boiler from the radiators. Leave it for at least overnight. If the pressure still drops, the leak must be from within the boiler. If the pressure does not fall, then keep an eye on the pressure gauge as you reopen the valves. If it then drops, the leak is in your radiator/pipework system.

This all depends on how quickly the pressure is dropping. If it's dead slow, then you may struggle to ID this with just an overnight test.

I've had a bag over the outside pipe and there was no water in it the next day. 
As for checking the pressure drop overnight, it doesn't drop that fast for me to see in just a few hours. If the pressure is on 1.5 bar I'd say it would be 4-5 weeks before it drops to around 1. 
  Once the weather picks up soon, I assume this method would still work if it is monitored for a month?
We have a  logic  combi espi 35 which is 2 and a half years old. If it's a serious fault I'll call them to
see how I'm covered. It's slightly complicated by it being already in a new build when we moved in but I did register it.
 If it does turn out to be on the heating pipework system and I still can't find it, do any of those leak fix adatives actually work? 
Thanks for your help 

ThisIsWeird

I think the combi should run in pure DHW mode with the two valves closed, so that should give you all the time you need to monitor the pressure fall. Obviously fully turn off the CH side so it doesn't try and supply this! Perhaps drop Ideal a quick email/chat to ask if doing this is ok, and monitor the boiler pressure when the DHW is running for longish periods, such as for a shower.

What paperwork did you get with the boiler? It should really be warranted for a lot longer than 2.5 years, but an annual service may have been part of this arrangement - have you done this?

I've had no personal experience of leak sealers, but would imagine that a slightly weepy solder of compression fittings may well respond to it. I can't see plastic fittings doing so, or parts like the Main Exchanger. 

If the MainX has gone, almost certainly you'll be able to claim for a fix - they should last a decade or more, no excuse.

Cap066

ThisIsWeird said:

I think the combi should run in pure DHW mode with the two valves closed, so that should give you all the time you need to monitor the pressure fall. Obviously fully turn off the CH side so it doesn't try and supply this! Perhaps drop Ideal a quick email/chat to ask if doing this is ok, and monitor the boiler pressure when the DHW is running for longish periods, such as for a shower.

Well, I checked with the pipe below the boiler  overnight. Not a drop of water in 11 hours so unless there is something else in the boiler (apart from the heat exchanger and expansion vessell) which can cause a drop in pressure, it looks like my heating system somewhere in the house has a leak. Which puts me back to square one as I've checked every visible connection and radiator and not found a leak. No damp patches anywhere either.  I need to confirm this as mentioned before by turning off the flow to the heating for a month. Is the boiler pressure running just hot water a big concern if I do this? Or are there other potential problems by turning off the flow to the CH? 

Albermarle

 If the pressure is on 1.5 bar I'd say it would be 4-5 weeks before it drops to around 1. 

If it is a leak, then it is a small one, which maybe is why you are struggling to find it .