Bubbles/Air in CH system

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Hi

I know this has been covered many times before but I've searched and can't find the answer to my problem.

I have a Combi Potterton Flamingo boiler with a Terrier Pump TC6.

On start up, everything sounds and works well, pump is quiet and smooth, radiators heat up but after about 30mins to an hour, the pump gets noisy and if i switch of the CH, i can hear bubbles bubbling up the pipes.

I've bled the radiators and pump and there is no air coming out of them.... Where could this air be and how can i get it out ?

Cheers
Adam

 

[45yearsagasman]

Describing your system layout would help us, and the Flamingo I remember is not a combi.

 

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We have the FLAMINGO RS 20/35 RS 35/50.

I'll try to explain as best i can, it looks very confusing....

Its a fully pumped system. Has a Honeywell switch, hot water tank and a expansion tank in the loft.

The hot water tank has 4 ports, 1 at the back (cold water feed to fill the tank), 1 at the top, 1 at the bottom and 1 in the middle.

There are 2 vent pipes... one coming of the pipe out of the top of the hot water tank and one near water pump.

I believe the system pumps the hot water from the boiler, through the Honeywell switch which then goes to either/or both the hot water tank and the radiators and then back into the boiler completing the circuit.

Cheers
Adam

 

[JohnD]

It sounds like you are describing a conventional open vented Flamingo with a feed and expansion tank in the loft and a hot water cylinder. It is not a combi.

Go into the loft and look at the feed and expansion tank. Is it warm? How deep is the water?

 

[Nige F]

Time to get a Sussex Plumber to have a look

 

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It sounds like you are describing a conventional open vented Flamingo with a feed and expansion tank in the loft and a hot water cylinder. It is not a combi.

Go into the loft and look at the feed and expansion tank. Is it warm? How deep is the water?

Water is about 3 or 4 inches deep. The water level is control by a ball float valve. The water is warm ish.

The pipe which comes out of the bottom of the expansion tank is hot and and i can see hot water coming out of it into the expansion tank. From the expansion tank, this pipe leads to a T piece which connects to the top of the hot water tank and to the hot water supply pipes for the house.

Cheers,
Adam

 

[JohnD]

From the expansion tank, this pipe leads to a T piece which connects to the top of the hot water tank and to the hot water supply pipes for the house.

Are you sure?

can you post some pics of the hot water cylinder, the expansion tank, and the pipes around and between them.

 

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Sorry, my bad. The bottom pipe of the expansion tank goes to the pump.

Ok, here is my expansion tank. The pipe on the far right is a vent pipe which connects to a T piece which connects to the top of the hot water tank and to the hot water supply pipes for the house.

The pipe in the middle is another vent pipe coming from the cross section by the water pump.

The pipe on the left is the feed pipe from the expansion tank to my pump.

This is the T section on top of the hot water tank:

This the water pump and 3 way valve. The pipe which is directly connected to the top of the pump is the pipe which leads to the expansion tank. The pipe on the right of the pump which is connected by a cross section (at the very top of the picture) goes to a vent pipe and also down to the boiler.

Hope that helps.

Appreciate the help.

Cheers,
Adam

 

[JohnD]

I can't really follow it.

Perhaps someomone with a more skilled eye will make it out. When the pipe run is confusing it may help to follow the vent pipe down its path from the top, putting a dab of coloured paint on it to help identify it.

the pipe that comes out of the top of the cylinder will not be relevant.

Are there any signs that water ever comes out of the vent pipe over the top of the tank? the top of the hook should preferably be a couple of feet above water level.