Overfilled Baxi Solo 3 and now it's leaking

[gizmotech]

Hi Mandate, thanks but it seems to have done the trick. Have been observing it for 2 days but point taken about the volume of air side. The only reason why I did this was because by filling up the vessel, to 0.6 bars, I have been able to bleed the system via the PRV. Now I know this is not the correct way of doing things, but as the PRV was the highest point within the system, it just made sense. On top of this, I could not find anywhere else to bleed the system.

I just felt that if I emptied the vessel and pressurised the bottom half with air first, then there will still remain air on the top half of the vessel, thus by filling the top half of the vessel with water following pressurising with air, there will be some air still present within the system. At least that at the time it seemed to make sense.

I have now taken your advice and released all pressure via the PRV until the last drop of water can be seen via the discharge pipe. Filled the vessel with 0.5 bars (as that is what it says on the vessel) and then filled the system until the presure on the indicator is sitting at 1.1. Have I done it correctly? Besides, can the water in the vessel ever be totally emptied as the PRV is at the top therefore under the assumption it will still hold water?

 

[MANDATE]

If the PRV was open when you charged the vessel with air, the diaphragm would push any existing water from the vessel back and discharge it. This would leave the maximum amount of air volume, which is needed to prevent problems.
Then after closing PRV and applying water to about 1bar the diaphragm is moved in the opposite direction slightly. This is how it should be before the heating is switched on.
As the air is compressed its volume reduces and its pressure increases.
This is indicated by the pressure gauge on the water side.
The pressure rise when heating is switched on, will indicate how satisfactory it is. Too big a rise and reaching 3bar indicates something wrong.

You need not worry about air in the water side. Some may be collected in radiators and can be bled. (bleeding will mean adjusting water pressure)
Air in other areas will rise and be discharged through the AAV (automatic air valve)
So the pressure is set to 1.1bar. What pressure does it rise to with heating on?

 

[gizmotech]

Told the missus to observe it but she keeps forgetting. Nevertheless it has behaved since. You were right though about pressurising the vessel first as the way I done it, the gauge would reach around 2.5 bars and would fluctuate quite a bit. Done it the way you adviced and now the gauge does not go over 1.5 bars (sits between 1 and 2).

I noticed that turning the room stat in between 1 and 5 makes no difference. However turning the room stat below 1 switches the heating off. So it looks like there is just 2 positions. I am thinking that the room stat is probably faulty. It is an old Satchwell one. Are they running of mains power or 12V via the boiler transformer? Also would I be able to replace it with any thermostat such as a Honeywell or for the Baxi Solo 3 does it hve to be a certain kind?