pumping over into f+e tank

[jay1]

hi all,
i have come across a slight problem, its an open vented system with a netaheat boiler, what happens is after the heating or hot water is turned off a little bit off water discharges into the f+e tank. this has happened after it has been powerflushed.
I have replaced the tee pipework section to the pump from the f+e after being told that may be the cause.
any ideas guys

 

[cider]

If that is the only time it happens, personally I wouldnt worry about it.

 

[GodKnows]

How big your system, rooms, rads etc... What setting your pump is on? Depends, how much water are you talking about? Off topic, cider owe you an apology fella

 

[jay1]

its only a tiny bit of water. the systems got 9 radiators in it. pump settings on 2. have told the customer to wait a few days and see if it still overflows out the overflow for the f+e

 

[RigidRaider]

Am I missing something here? Surely the expansion tank is designed to do exactly what yours is doing. i.e. collecting the overflow when the water in the system expands as it heats up.

????

 

[JohnD]

It is supposed to expand quietly up the F&E pipe that goes into the bottom of the tank

I presume the OP means it is spurting up the vent pipe. This also traps dissolved air in the water which is not helpful.

If this is so:

How far above the water level in the F&E tank, is the bend in the vent pipe where it hooks over the F&E tank? How deep is the water in the F&E tank? Often increasing the "head" of the bend above water level is enough to hold back the odd spurt. You can do this by lowering the water level (a couple of inches water depth is enough) or by lengthening the vent pipe to make the bend higher.

Even easier is to turn down the speed of the pump a bit. They mostly have speeds 1, 2 and 3

It can also be caused by errors in the positioning of the F&E pipe, the vent pipe and the pump - have a look where these are, and measure the distances between them. This is more work to change. Post a photo too which may help.

 

[yerino]

Am I missing something here? Surely the expansion tank is designed to do exactly what yours is doing. i.e. collecting the overflow when the water in the system expands as it heats up.

????

Before you do anythin to drastic, try two things.

1) turn your pump speed down.
2) raise your vent pipe abit.

...

You should not have pumping over as this causes potential blockage problems in the future because of deoxgenation.

 

[cider]

How big your system, rooms, rads etc... What setting your pump is on? Depends, how much water are you talking about? Off topic, cider owe you an apology fella

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