Is this the pressure release valve? (photo)

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If anyone can advise. thanks.

Boiler was at 2.2 when I left it last night, had dropped to 1 this morning and needed the wras lever turning

it currently at just over 3 - which I'm aware is too high for comfort? When I turned the wras lever this morning, it kicked in at about 2.0


prv.png
 
No. That has a cable coming out of it, I'd guess it's a temperature sensor but I could be wrong. There's 2 types of PRV, a pressure reducing valve which you would fit to a cold main and a pressure relief valve which is part of the heating circuit to prevent overpressure, they're 2 completely different things. This is a diy forum and people will help where they can with simple jobs, I think this is a job best left to the professionals though.
 
re call out - of course. I'm absolutely going to get a call-out to have a check over it [assuming it doesn't explode before then] Do you or anyone know where on these two images it would be? I've consulted google, and the results don't seem to be in the photo

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This is a Warmflow pressure relief valve, should have a pipe comin off it going to waste, sometimes there isn't this waste pipe.

thanks....there absolutely doesn't seem to be anything that looks like that, that I can see
 
The pressure relief valve on my Firebird is screwed directly into the top of the boiler, not familiar with the Warmflow.
 
if the pressure is at 3, can I manually press something in to lower it to 2 for example? right now it hasn't blown up (touch pipe.....) so I'm as inclined to just leave it until I phone someone. I did just try a small bleed from the top of the towel heater (highest point) and a tiny amount of apparently clear liquid came out
 
I've just found this. I wonder? one white pin with no red cap over it. That's comes from a flexi pipe which comes direct from the pressure dial pipework. maybe someone (a call out) has been playing with it, and didn't put it back on (previous owners/tennants/call out I'm guessing)


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I've just turned the thermostat down for half an hour to switch it off, pressures gone from approx 3.1, to 2.6. have switched it on again. can anyone possibly confirm that the bare white pin is the pressure release valve? would I press that down to take the dial down from 3.0? (5 minutes later) yeah it's humming along again at 3 now
 
You don't vent pressure at the relief valve, its there to automatically vent pressure in an emergency. Bleed a radiator, that'll take the pressure down.
 
ok thanx. I've just done 3/4 turn of the towel radiator ("top" of the system), just a tiny amount of water came out no air, I tightened it back up. Do you think that bare white pin is the pressure valve, and someone didn't replace the red cap?
 
A pressure Relief valve has no flow through it, see it again in the below attachment, there is pressure via the bottom connection which is either connected directly to the boiler or teed into the pump inlet or outlet pipe (HAVE YOU CHECKED THIS??) as shown in post #8 with a waste pipe (sometimes coming out) which, if the PRV lifts at 3.0bar will pipe the water off to drain.
Attachment below, also shows the back of the boiler with the pressure relief valve outlet, check this out as well, you should have access to the boiler casing rear.

Your other thread showes a (combi) boiler water contents of 74L, if so, then because you are filling the boiler to ~ 2.2 bar, it is almost sure to lift the PRV (3.0bar) as a 12L EV (with a fill pressure of 2.0/2.2bar) will only cater for 95L total system contents leaving only 21L for rads etc.
As a very interim measure suggest filling to 2.2bar initially to reset the faulty pressure switch, then very slowly release pressure via a rad vent until the pressure falls to say 1.5/1.8bar, this may still keep the pressure switch closed and enable the boiler to fire, the PRV should not lift then with a hot boiler.
My advice is to get someone ASAP because your rads/system will quicky build up sludge due to this continuous topping up.
 

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ok that diagram doesn't appear to correspond to the boiler layout I have. again half of the rest of that was foreign (I have no idea what a rad(iator) vent is -- or where it is, or where the inlet or outlet pipe is without going over the text on a print out without it in front of me. I'm just fishing for any basic things I can try before a call out, without the risk of damage, which I definitely run the risk of doing. of any equipment I'm familiar with, boilers definitely aren't one of them. I'd need a physical demo of how to adjust the rad vent, which obviously I'm not going to get yet at the moment

right now best I can do is monitor the gauge when I switch off at night, and compare it to the morning. so far I've learnt that the pressure gauge is the actual radiator water system (going by the hiss when I change the blue valve, I thought the gauge was some seperate system inside the boiler that showed air pressure). and I've learnt that 3.0 is too high

but the fact that it's losing pressure.....means that liquid inside the pipework is leaking out somehow overnight? nothing appears to be wet from anything visible
 
All rads will have a vent/bleed screw like the one you slackened......"I did just try a small bleed from the top of the towel heater", there is no adjustment as such, its a "vent" screw while air comes out and a "bleed" screw while water comes out, you just slacken it a 1/2 turn or so and put a dish or something under it and keep bleeding to give you the required boiler pressure, you then shut it.

If you can't locate the circ pump then its unlikely that you can locate the PRV.

Would agree that there should be some signs of water if the PRV is lifting/passing with that level of top up.
 

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