Oil boiler in low water pressure location. Pump problem.

[John.g]

Logically. if there is air ingress then some part of the system must be running with negative pressure which might point to a blockage somewhere in the system. I would still prove the E.vessel and associated pipework correct and totally clear.
As a very basic check just remove the plastic cover at the EV air end and press the schrader valve with your finger, air only should come out.
You could also get a bicycle pump and increase the whole system pressure from the EV air end but only by 0.3bar or so as you are reducing its effective volume.

 

[stevef]

Logically. if there is air ingress then some part of the system must be running with negative pressure which might point to a blockage somewhere in the system. I would still prove the E.vessel and associated pipework correct and totally clear.
As a very basic check just remove the plastic cover at the EV air end and press the schrader valve with your finger, air only should come out.
You could also get a bicycle pump and increase the whole system pressure from the EV air end but only by 0.3bar or so as you are reducing its effective volume.

Ok, I'm going to look at that. I'll google some of those words, eg schrader, and that will give me an idea what to look for. This is new ground for me.

 

[John.g]

Its just a car type valve at the air end of the E.vessel.

Regarding the "steam" one must remember that the overtemp stat on the Firebird doesn't operate until ~ 110/113C so as pointed out above the pump could be "lazy" or on the way out but you possibly would see a slow HW cylinder warm up time and slow rad heating.

If the HW coil flow and return pipes have a big temperature difference on HW only then this may indicate poor circulation as well.

 

[stevef]

Its just a car type valve at the air end of the E.vessel.

Regarding the "steam" one must remember that the overtemp stat on the Firebird doesn't operate until ~ 110/113C so as pointed out above the pump could be "lazy" or on the way out but you possibly would see a slow HW cylinder warm up time and slow rad heating.

I think I might have been on those lines when I reduced temp of boiler. Gotcha re valve, I'm going to progress some of these points tomorrow. I've turned the pump down to 2, which is where I thought it was, and retry.

 

[stevef]

I've just thought of something. While I'm trying to fix the problem, I'm not using the timer control unit. I'm just leaving HW on permanently, and using the power to the whole system. Is there a system by which the pump carries on after the timer goes off? To run the heating water around for a while? I can see how this might cause a problem if it can't run any air around to the bleed upstairs by the tank??

 

[John.g]

What you can do is just run the circ pump from a extension lead and plug and vent away (cold) for as long as you like, just latch open manually, any zone valves.

 

[stevef]

What you can do is just run the circ pump from a extension lead and plug and vent away (cold) for as long as you like, just latch open manually, any zone valves.

Right John, I'll do that if (when) I need to. Today water was less than luke, after she had her bath last night. I started today with no bleeding, at pump or anywhere, and it worked fine, could tell immediately I had circulation, and boiler came on and off as you would expect (so HW not stopping in boiler). Wondering if everything I tweaked was irrelevant, just had to purge and purge and purge, and now its there or getting there. One swallow isn't a summer, but I have hope. See what tomorrow brings.

 

[John.g]

Is there anyway you can purge/check for air in the boiler top, I wouldn't be happy that you havn't got a intermittent pump problem unless I could do this via the PRV of whatever.

 

[stevef]

Is there anyway you can purge/check for air in the boiler top, I wouldn't be happy that you havn't got a intermittent pump problem unless I could do this via the PRV of whatever.

I'm away from home until this evening, and then I'll look to see whether there is a way to purge there. I always hear the pump working, it seems to be a question of whether spinning in air or water. It always seems that bleeding the pump fixes the problem for that burn, but air then seems to collect there again - unless there was another sort of pump problem you were thinking of?

 

[stevef]

Is there anyway you can purge/check for air in the boiler top, I wouldn't be happy that you havn't got a intermittent pump problem unless I could do this via the PRV of whatever.

Hi John, back late. But I have run the system again without problem. You asked about way to purge at boiler top. Is this it? And if so, is it obvious what to do with it?

 

[ShaunCorbs]

No not that don’t twist that

You will either have an auto vent or two like what you have in your rads

 

[John.g]

Hi John, back late. But I have run the system again without problem. You asked about way to purge at boiler top. Is this it? And if so, is it obvious what to do with it?it looks like a 3bar PRV but too much electrics

Hi John, back late. But I have run the system again without problem. You asked about way to purge at boiler top. Is this it? And if so, is it obvious what to do with it?View attachment 64219

No, leave well enough alone as you are now running OK. I am not familiar with that type of PRV as it seems to have a temperature capilliary attached to it, just from a safety aspect ensure that the other side of the PRV is attached to a pipe that goes to waste.

This is what a PRV looks like with that open end going to drain.

 

[exedon2]

The small pipe of prv is connection for pressure gauge

 

[John.g]

Where is the vent??

 

[John.g]

I think I might have been on those lines when I reduced temp of boiler. Gotcha re valve, I'm going to progress some of these points tomorrow. I've turned the pump down to 2, which is where I thought it was, and retry.

The two thermostat (control&hi limit) sensors are located where shown, they are in a dry pocket that is screwed into the top of the boiler.