Noisy Boiler first thing in Morning....

[Alek Snart]

Hello all,first post here on what looks an excellent site.

Boiler is a Glow Worm Spacesaver RF wall hung in downstairs kitchen.
House is bog std 3 bed semi.
System has performed faultlessly for years but in past couple of months (Oct 2007) has had a worsening symptom.

On first startup each morning the system exhibits a selection of noises as if one had turned on the water supply into an empty tank.
As the boiler ignites and the motor starts turning one may hear a selection of Gurgles,Whooshes and assorted other amplified swallowing sounds...GULLLLLP....(Hope that`s descriptive enough)

Initially these sounds only persisted for perhaps 30 secs,but since October last they have been remaining sometimes for up to 10 minutes.

The general performance of the system remains excellent with no drop in heat output.
The only attempt I have made at a fix involved bleeding the only sensitive radiator on the system,located in the box room which occasionally requires a bleed to get it fully operational (once per season ).

The circulation pump (Wilo) is in the upstairs airing cupboard along with the hot-tank and much assembled clutter .

 

[gas4you]

Check your F&E tank is full in the loft.

If it is drain some water out of the system and see if the F&E fills up as you are doing it.

If not you have a blockage in the cold feed.

 

[Alek Snart]

Just down from the attic.
Smal tank full and ball valve working...however....The I found shepherds crook vent pipe which sits over the tank was sitting very low and actually touching the surface of the water ....Would this cause some form of problem ???

 

[martyc]

It should be above the tank by a few inches, but doub t its causing your problem.(see if you can shift it up to ensure it doesnt contact the water in F&E)
Re-read the gas4you reply...i dont think you followed what he asked you to do.(drain from system and see if tank emptys)
marty.

 

[Alek Snart]

Sound man Marty,Visitors have interrupted investigations but on further checking the F&E tank I find it full almost to the overflow.

Water temp is cold and the sides of the tank itself are coated with a fairly thick greenish coloured "Gloop" which however is not floating about in the water itself.

I shall do the drain test as soon as I can.

Will opening the most accessible Rad bleed valve induce enough of a flow to test this ?

 

[keego]

Will opening the most accessible Rad bleed valve induce enough of a flow to test this ?

No, you will need more flow than a vent will give you. See if you have a drain off on the pipework & fit a hose to it then turn it on so it's just trickling out.
If when you do that it drains then bend the float arm down so the level is lower & well below the expansion pipe.

 

[Alek Snart]

Ok people,Just down from attic.
With the somewhat reluctant assistance of Mrs S I set up a draining operation from the most extreme Rad in the system.

I drained down nearly 75mm of water from the F&E`s previous level.
At this new level the ball valve is just beginning to open and as it`s quite arkward to reach the arm to adjust it,I decided to use this as my reference for any further investigations.

I spent 20 minutes sitting,watching and listening to the activity in the F&E which thankfully (?) amounted to nothing.

I then had "her downstairs" switch on the system and the only item of note was a single large air bubble and rumble as the system kicked in.

As I said earlier the Inside surface walls of the F&E tank are coated with a very slippy goo some of which came away as I rooted with the Ball Valve arm.

The water bled off from the rad was initially black but cleared out fairly rapidly to normal consistency.

Hope this gives the helpers a better idea of what`s about ?

Thanks one and all for the interest and suggestions.

 

[Alek Snart]

Sofa....Sogood...System still bubbling and gurgling away at startup.
After draining down the bottom rad I bled out a couple of the others also,but no huge volumes of air were apparent.

Then I decided (foolishly ?) to bleed the circulating pump.
With the pump off I undid the central spindle cover and watched as a very insipid trickle of water dripped out..although there was no great whoosh of air either,just a poor dribble of clean water.

Is this a normal flow for a c/pump ?

Upon restarting the system the usual whooshing is still present...?

The plot thickens ?

 

[JohnD]

pumps should only drip when you take the central screw out, it should not gush out.

If you F&E is very dirty it would be useful to bale out sludge and scrub it clean and put a lid on it to keep dust and wildlife out.

It sounds like it does not have inhibitor in it (these usually prevent growths as well as corrosion)

If the water was black this indicates corrosion of the radiators (the black is sludge, which can also cause partial or complete blockages and poor circulation. It tends to collect in narrow pipes and the bottom of radiators, also in the boiler. there can be a large amount in old open systems).

You can give it a chemical clean and flush easily enough at low cost, as long as you have easy access to the F&E and the drain cock.

I am just a householder and I don't know if the presence of sludge is the cause of your problem. It is just one of the things that need doing.

The bubbling and gurgling sounds like air but I don't see why it won't rise up into a radiator instead of being trapped in the boiler. maybe you can post some pics of the pipework round your boiler and cylinder is case there is not an easy rising run for air to escape upwards.

Also look at the ball cock in your F&E and see if it has been dripping, since you say the water level was higher than the float setting.