yellow gunk in header tank

[fabgav]

Hi all.
I put some system cleaner in a few months back, left it in for a week as per instruction then flushed the system and added an inhibitor.

The boiler has been making ghostly whirling noises lately.
I've bled every value and the pump but no air.
Checked the header tank and found it to be steaming. the feed pip from header to system is hot, as is the expansion pipe.
The water in the header tank is........well grim, its STINKS and has a yellow gunk that is clinging to the sides.

Untitled

• fabgav
• 26 Nov 2014
• 1

Anyone got any ideas what this is?
It was never there in the 4 years before i put this inhibitor in.
It is always covered so doubtful its a dead animal.

Also, i've read somewhere this could be due to the heat exchanger coil broken in my cylinder?

Any pointers appropriated.

Thanks

 

[Plumber90]

When you put the system cleaner in did you drain the heating system down a bit first.

 

[fabgav]

Also, i've just thought, the hot water is stupidly hot, even when i turn the thermo down on the boiler.
I think i have smelt a funny smell from the hot water too, so this would suggest the coil problem?

Is there another way i can test the cylinder?

thanks

 

[fabgav]

When you put the system cleaner in did you drain the heating system down a bit first.

that was a fast response.

I drained it fully, added cleaner then left it a week and drained fully again.

 

[Plumber90]

1 minute response, that's a bit slow for me

Did you notice whether or not it was like that before ?

 

[fabgav]

it was definitely not like it before.
Its only happened since doing the cleaner and inhibitor

 

[JohnD]

it probably has bacterial slime.

bale a bit out into a bucket and see if there are strings or jelly in it.

Bale out the f&e, sponge it clean, wipe it with bleach (including the lid and the valve); buy a bottle of Fernox AF10 biocide.

Preferably drain out the system and clean or at least rinse it through to remove traces of contamination before you refill. If the vent pipe is hot it may be pumping over, so give it a chemical clean with X400 or similar. Observe if the water changes colour once the cleaner starts circulating. It may go black, brown or orange with loosened sediment.

Use a Fernox or Sentinel inhibitor when you refill, and add the AF10 to the F&E according to the instructions.

If the F&E does not have an insulating jacket, get one. This is to prevent it getting warm and stagnant during summer, and not just, as you might think, to prevent it freezing.

The tight-fitting plastic lid will prevent dirt and drowned wildlife rotting in the water.

Also, i've just thought, the hot water is stupidly hot, even when i turn the thermo down on the boiler.

so turn down the cylinder stat, not the boiler stat.

 

[fabgav]

Cheers for all that I will crack on this weekend.

One thing though, Where will my cyclinder stat be as I don't think I have one?

 

[Scarum]

Hi all.
I put some system cleaner in a few months back, left it in for a week as per instruction then flushed the system and added an inhibitor.

The boiler has been making ghostly whirling noises lately.
I've bled every value and the pump but no air.
Checked the header tank and found it to be steaming. the feed pip from header to system is hot, as is the expansion pipe.
The water in the header tank is........well grim, its STINKS and has a yellow gunk that is clinging to the sides.

Untitled

• fabgav
• 26 Nov 2014
• 1

Anyone got any ideas what this is?
It was never there in the 4 years before i put this inhibitor in.
It is always covered so doubtful its a dead animal.

Also, i've read somewhere this could be due to the heat exchanger coil broken in my cylinder?

Any pointers appropriated.

Thanks

I had the same issue, I used Sentinal X400 cleaner 6months before. As a matter of interest, did you also??

To fix this I tied up the ball-cock, bailed out everything from the tank. Wiped with bleach, added Fernox Af10, wiped everything in and around with it, replaced the floater and refilled.

 

[fabgav]

I'm glad to hear you had this problem from a good brand as I had used screwfix no nonsense stuff and thought it may be a quality thing.

 

[JohnD]

One thing though, Where will my cylinder stat be as I don't think I have one?

should be strapped to the side of the cylinder, about one-third up from the bottom. May look like
http://www.screwfix.com/search?search=cylinder+stat

with a (usually) white silicone-rubber or shiny black heat-resistant flex in it.

more often than not a Honeywell or an ACL Drayton.

If the cylinder has a red jacket it may be concealing the stat.

If there is no cylinder stat, your system is probably very old and rather inefficient. There might be a Cyltrol or a Tapstat attached to the return pipe from the cylinder to the boiler, post photos please. If so it is probably very old and may have seized.

 

[fabgav]

Hi, sorry for the late reply.

Definitely no cylinder stat and no Cyltrol or a Tapstat

What is the best way to test for loop leak? block off F&E tank and drain off some from CH system and see if cold water storage tank fills?

 

[JohnD]

drain or bale out whichever is lower, ties up the ball float, observe if it refills..

With no cylinder stat you are tipping money down the drain. Photograph the pipes around the cylinder, and pump, and boiler and any motorised valve you can find.

 

[fabgav]

Nothing to show around the boiler only a drain off valve,
but here is my airing cupboard.

If a cylinder stat is fitted and say the tank water is at 60' but the central heating need more heat, how does the boiler know to kick in?

in fact, how does the boiler decided to kick in at all?

Untitled

• fabgav
• 2 Dec 2014
• 1

 

[JohnD]

the grey metal box is a motorised 2-port valve it (should) turn off heat from the boiler to the cylinder when there is no HW demand. In your case, with no apparent Cylinder stat, I don't know how it works (if at all). It may be that your system has poor controls, which will waste energy (money)

http://www.screwfix.com/search?search=2+port+valve

Possibly you have another 2-port valve on the radiator circuit.

A three-port valve is rather more common, it sends heat to the cylinder, or the radiators, or both, depending on demand from the cylinder stat and the room stat.

http://www.screwfix.com/search?search=3+port+valve

Those hot pipes should be insulated.

the hot water is stupidly hot

due to lack of a cylinder stat, I expect.