We have had a bit of bother with a gurgling noise from the Alde header tank. The system would operate quietly for about 45 minutes or so. Soon after, the header tank starts to sound like a pan of hard-boiled eggs on the stove! Switch the system off, and immediately the noise stops. The noise does not rumble on for a few seconds, the noise ceases immediately. This suggests air in the system. However, the system has been bled repeatedly. Switch everything back on, and within moments, those hard-boiled eggs are boiling away again. Consequently, we have gurgling noises coming from within the Alde header tank.
Listen to the gurgling noise from the Alde header tank!
Have a look at the video – you can imagine what this is like at two thirty in the morning!
I followed the manual and bled the system – no success! – The sound of the boiling eggs continues! One suggestion is to do with air bubbles trapped under the impeller within the 12v pump. The present 12v pump is within the header tank. Make sure your impeller pump is not screwed on too tightly. This can cause vibrations and hence the gurgling sounds.
Our solution to the gurgling noise from the Alde header tank
As a resolution to this gurgling noise from the Alde header tank, I had arranged for the Alde system to be looked at. Partially at my request, the 12v pump within the header tank was removed.Consequently, a new 12v inline pump wasfitted to the side of the boiler. As the Tremeloes said, “silence is golden”. There is no longer a gurgling and murmuring noise from the Alde header tank. The 12v inline pump is quiet in operation. The pump has a manual speed setting, 1,2,3,4 and 5. It is currently set at 2, with 1 being the lowest and 5 being the highest. I understand that the highest setting should only be used when bleeding the system.
We have however retained the 12v pump that was sat within the header tank, so this can be re-fitted in case of failure of the 12v inline pump.
Prices and parts for the system are on the Alde UK website.