Vaillant ecoMax 800 Pressure

[Aromatical]

Hi, Hope someone can help.

Initially the pressure is set to just above 1 Bar. When the heating is on, the pressure keeps on rising up past the green area. Eventually water is seen dripping off the base of the expansion bottle but coming from somewhere at the top which is peculiar as the connection is at the bottom. After a couple of days of this, eventually water pressure drops to zero and the systems cuts out as it is supposed to until it is refilled again.

Anyone know what is at fault here?

 

[Aromatical]

Just some extra information.

The pressure in the expansion tank is at about 1Bar so it is still charged to the correct level.

 

[mickyg]

how did you check the expansion vessel pressure? if this is definately ok then the pipe connecting it into the system is blocked.

 

[Aromatical]

Thanks for the prompt reply.

I checked the pressure at the charging valve.

What would explain the water dripping at the bottom of the expansion tank and wouldn't the pipe being blocked to the expansion tank cause the PRF to operate? Which it hasn't.

Any other ideas?

 

[twgas]

the question was HOW not WHERE.

water dripping usually means a leak - it may run down from further up.

 

[kevplumb]

the question was HOW not WHERE.

now now mickey

with a pressure gauge and the system full of course

 

[Aromatical]

I checked it with a pneumatic charger with an encorporated gauge at the charging valve.

There is nothing above the expansion valve within the boiler and there are no apparant leaks from the pipes above the boiler.

 

[Aromatical]

Addition, With the system off and cold.

I assume you mean with CH valves closed and pressure releaved?