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Notagainpike

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Hi all...got some issues....drained my working ok system yesterday to upgrade some 15 to 22 on the flow and return rad circuit.
Refilled and bled up.
Fired boiler up, had hot water and rads for 3-4 hours...
Turned off to cool.
Boiler would not fire on timer later, demand wouldnt work either....
Noticed that the pump when working did sound like it was passing bubbles...if that makes sense...?
Also, boiler temp was very high, and heat exchanger was boiling hot to touch.
This morning no hot water or heating on timer fired boiler, so i switched both to demand, i think the boiler woke up, but temp went from 30s to 102 in a couple of minutes.....

Last night i cracked the bleed nipple at the bottom of the heat exchanger and there was water present.

Im assuming i have air locked boiler?

I never had any problems like this with the gravity fed system....
 
99% sure it will be air

Check to ensure heat exchanger is vented, system filter too (I've had systems where nearly all air is caught in the filter and it takes ages to keep bleeding it waiting and then repeat). Once everything is vented properly then you need to start getting some flow moving and the pump will soon clear the air. Start with your hot water only.

If your boiler isn't firing still and it sounds like the pump is cavitating then unplug the connector for a second or 2 or hold the switch between 2 different speeds to stall it, this will let the air escape and allow the pump to keep trying to clear the air.

If you have no luck with the hot water (I had one this week) then run the heating only and shut down every radiator but one, if you have a Y plan make sure you turn your cyl stat down to ensure the valve shuts the hot water. Then go round once and turn a new rad on and the old one off each time they get hot, then finally introduce the hot water.

A photo of your pump and pipe work in the airing cupboard may help too
 
Yep air locked try running on hot water only if you have a cylinder
 
fowlerboi said:
99% sure it will be air

Check to ensure heat exchanger is vented, system filter too (I've had systems where nearly all air is caught in the filter and it takes ages to keep bleeding it waiting and then repeat). Once everything is vented properly then you need to start getting some flow moving and the pump will soon clear the air. Start with your hot water only.

If your boiler isn't firing still and it sounds like the pump is cavitating then unplug the connector for a second or 2 or hold the switch between 2 different speeds to stall it, this will let the air escape and allow the pump to keep trying to clear the air.

If you have no luck with the hot water (I had one this week) then run the heating only and shut down every radiator but one, if you have a Y plan make sure you turn your cyl stat down to ensure the valve shuts the hot water. Then go round once and turn a new rad on and the old one off each time they get hot, then finally introduce the hot water.

A photo of your pump and pipe work in the airing cupboard may help too
Click to expand...
OK...heat exchanger vented as in....?
 
fowlerboi said:
99% sure it will be air

Check to ensure heat exchanger is vented, system filter too (I've had systems where nearly all air is caught in the filter and it takes ages to keep bleeding it waiting and then repeat). Once everything is vented properly then you need to start getting some flow moving and the pump will soon clear the air. Start with your hot water only.

If your boiler isn't firing still and it sounds like the pump is cavitating then unplug the connector for a second or 2 or hold the switch between 2 different speeds to stall it, this will let the air escape and allow the pump to keep trying to clear the air.

If you have no luck with the hot water (I had one this week) then run the heating only and shut down every radiator but one, if you have a Y plan make sure you turn your cyl stat down to ensure the valve shuts the hot water. Then go round once and turn a new rad on and the old one off each time they get hot, then finally introduce the hot water.

A photo of your pump and pipe work in the airing cupboard may help too
Click to expand...
Il put a pic up
 
Valve and pump arrangement
 

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Right so its not open vented.

Typically sealed systems are incredibly easy to get air locks out of.

Just to be sure, that's an old photo right? As your pump and valves aren't wired in.

Need a photo above the boiler of pipework arrangement too and one inside to tell you where to vent the heat exchanger, surprised though with a sealed system the pump won't clear that.

Check what speed your pump is set too and then turn it down to 1 which is the slowest, this may help prevent cavitation until the air clears
 
fowlerboi said:
Right so its not open vented.

Typically sealed systems are incredibly easy to get air locks out of.

Just to be sure, that's an old photo right? As your pump and valves aren't wired in.

Need a photo above the boiler of pipework arrangement too and one inside to tell you where to vent the heat exchanger, surprised though with a sealed system the pump won't clear that.

Check what speed your pump is set too and then turn it down to 1 which is the slowest, this may help prevent cavitation until the air clears
Click to expand...
 

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Try this. No guarantee that it will work but you have few options. Completely lose the bottom pump valve. Slowly loosen the top pump valve's compression nut, water / air will bleed out and may be enough to release the air lock.
 
Close all but one rad closest to the boiler upstairs turn ch on and ramp the pump upto 3 if it’s not already on it and let it run
 
ShaunCorbs said:
Leave it don’t reset if pump is running
Click to expand...
Pump had stopped, started after reset. Did this twice, then had f11, did another reset, opened the drain on the heating return and seemed to get air out, or at least water that was very oxygenated....?
Left it 30 mins got heat at the one rad with no valves that i left on, bled this and had loads of air, gradually bringing one rad back on at a time and bleeding out...
Swems to be going in the right direction....
 
Pumps controlled via boiler so yes keep resetting if faulting out once one rad gets hot and you’ve bled it a few times and topped the pressure back up if dropped open another rad and leave the good one as is etc

Will take time but should shift
 
ShaunCorbs said:
Pumps controlled via boiler so yes keep resetting if faulting out once one rad gets hot and you’ve bled it a few times and topped the pressure back up if dropped open another rad and leave the good one as is etc

Will take time but should shift
Click to expand...
Is the general oppinion that the system has been plumbed up wrong, ie. It needs a bleed of, or is it just some do, some dont secnario....?
 
Notagainpike said:
Is the general oppinion that the system has been plumbed up wrong, ie. It needs a bleed of, or is it just some do, some dont secnario....?
Click to expand...

It’s good practice to put air vents in if the boiler is above the pipework eg drops down
 
You can see from the diagram below anywhere the pipework goes upwards it should have an air vent (marked with an X). Radiators are massive catchments for air with an air vent. In theory

In the real world you can get over small high spots (such as floors being out of level), specially on a sealed system as its easier to clear. I'm one for never ever putting one in but I've seen tons of systems where some plumbers don't care

The second photo shows a system where no additional air vents are needed
 

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fowlerboi said:
You can see from the diagram below anywhere the pipework goes upwards it should have an air vent (marked with an X). Radiators are massive catchments for air with an air vent. In theory

In the real world you can get over small high spots (such as floors being out of level), specially on a sealed system as its easier to clear. I'm one for never ever putting one in but I've seen tons of systems where some plumbers don't care

The second photo shows a system where no additional air vents are needed
Click to expand...
Ah right interesting....
So a need for a vent before i settle up....?
 
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