Gurgling noises

[Gixxerman]

I had a new Worcester Bosch 12Ri fitted about 4 months ago.
I has been performing fine and my gas bills are a lot less than my old Apollo 15/30b.
However over the last few weeks, I have been having gurgling / whoshing noises from the hot water system. The whoshing noise is only there when starting from cold and seems to a lot worse when on water heating rather than central heating (I have 2 circuits with a 3-way valve). The central heating pump is currently on its highest setting (the apollo needed this as it was a low water content heat exchanger).

Then this morning I heard a trickling noise, like a tap being left on.
I located the source of the noise as the Magnaclean in the airing cupbaord.
Does the Magnaclean need cleaning?
I bleed the air out of the system by opening an air bleed valve in the airing cupboard (although very little air came out). This didn't fix the problem.
The radiators are make trckling noises when first starting from cold. You actually hear the noise traveling from one radiator to the next as it goes through the loop.
I have not bleed the radiators since the next boiler was fitted.
Could it just be air in the system?

 

[TheGasEngineer]

If you have vented heating system, you need to check there is some water in the F&E cistern.
If water present, then sometimes the feed pipe can block with scale where it tees into the main pipwork and the system can still run dry still with water in the F&E cistern.
Look for inverted pipe loops without air vents. Vents are required at all high spots.
There should be a bypass (see the boiler installation instructions) but with a three port valve and ensuring some radiators stay open you can shut a bypass gate valve. But pump overrun must always pump water somewhere. Better is an automatic bypass. Set the pump on #2; close all rad lock shield valves (LSV) to 1/2 turn open; run the system with windows open to shift the heat and check the cool side of each rad. open or close to get about 55degC. Remember that opening one cools the others and visa versa. do a few adjustments and wait for temperatures to settle. The boiler return needs to be approx 55degC. If all LSVs are wide open, put the pump on #3. If <1/2 open put pump on #1 and readjust.
HTH

 

[Gixxerman]

Thank you for the help.
However, I am a software design engineer and not a plumber so could you translate that into English please.
I know about the F&E tank and I will check that.
I have no idea if the rads have LSV's.

 

[ferret]

sounds like air mate , bleed your rads and see , don,t worry about the rest.

 

[TheGasEngineer]

So you need a functional design spec and and structured walk through...

You've asked me for a application design, and then how the language works; sort of a quick course in C++ with .net extensions...

The system could be running low on water. The feed pipe should, surprise, surprise, feed water into the heating circuit but an encrustation can form in the pipe and stop water entering the heating circuit so the water level drops causing air locks and hence the wooshing is water and air rushing around the pipes. A pump (or circulator pump for its full name) is not designed to increase the potential energy of water, it is only intendened to circulate it around a closed loop.

Air locks are a menace. Many systems suffer them. Cast an eye over every bit of pipe and imagine an air bubble rising. If it can get out by a vent or bleed valve then that's OK. Just open each vent. If not, have vents fitted where necessary.

Rads have either a handwheel valve (HWV - one that turns by hand) or a TRV (Thermostatic rad valve) and at the other end a copy of the HWV except ideally it should have a shield that prevents turning it by hand, a lock-shield or LSV. but often you get two HWVs which mean that people fiddle with them and wreck the flow of water which them upsets the temperatures of all the other radiators. If you adjust the radiator returns to 55degC then by definition the boiler return must drop to 55degC and your boiler will condense like mad and be really efficient. But you need water in the system first. Any good?

 

[Gixxerman]

LOL at GasEngineer.

Thanks everyone.
I have bled the radiators and all is quiet now.
Started with the downstairs ones and nothing much came out of them.
The upstairs ones were pretty much the same until I did the bathroom one (the last in the loop I think).
The produced about as much hot air as the average middle managers meeting.

One more question.
If I want to clean the magnaclean what do I have to watch out for?
I assume that I just shut the isolation valves, whip the top off the filter and wash the element under the tap. Will I need a new seal? Does the heating have to be off and cold to do the job?
Thanks.

 

[TheGasEngineer]

Well done so far. I have seen systems like this. If the plumbing is not ideal, radiators (and associated joints) can experience negative pressure. O2 is ingested through microscopic holes in joints and over time displaces the water.

To Clean magna clean
Prepare old bucket half full water (or empty depending on psychological state... See notes: disposal)
Boiler controls off.
Ensure pump stopped.
Turn off 2 x isollation valves.
Release pressure with bleed screw in top (see note below)
Wear diposable gloves
Undo top. Old seal fine if not been too tight.
place over bucket and withdraw magnet.
Rinse off oxide residues. (at this point if the girlfriend is a dippy bit, threaten with black hands and she'll do anything if you promise not to touch her with them... )
Remove water from Magnaclean canister and fill with corrosion inhibitor
Assemble in reverse order. Don't over-tighten. Maybe a thin, thin, thin film of silicon grease.

Note
To tighten bleed screw. Finger tight and only a little more if any drips.
To dispose of black residues: Its oxidised iron so should be ok for the garden. Don't quote me...
Tighening top: Take it easy. Just snugg. Tighen more if it weeps.

If lots of oxide investigate why. Limescale deposits on valves, the pump or other joints show tiny leaks. Filling from the F&E cistern (vented system) or filling loop (sealed system) introduces oxigenated water and perpetuates corrosion. Stop the leaks, the exisiting O2 is used up and corrosion stops.
HTH