Expansion vessel pressure keeps dropping

WIAWSNB

dharm999 said:

The boiler is around 10 years old, and the house was built around 23 years ago, so the boiler has been replaced, at least once.  No idea if the pump was changed at the same time as the boiler, or even in the time since the boiler was changed, is there any way to work out its age, if I can find a serial number for the pump?

I'd have thought so - ask Grundfos - they are very good at replying.

I'd assumed your pump would be younger than your system, but seemingly Grundie introduced their first Smart pump in 1991! That's the X99, apparently (AI...)

Anyhoo, I'd ask G. 

Albermarle

dharm999 said:

The boiler is around 10 years old, and the house was built around 23 years ago, so the boiler has been replaced, at least once.  No idea if the pump was changed at the same time as the boiler, or even in the time since the boiler was changed, is there any way to work out its age, if I can find a serial number for the pump?

The pump would not have been replaced if it was working OK, unless the customer specifically asked.
If the pump is that old, it is not that surprising if it is playing up. 

dharm999

Situation remains as weird as before. Pump hadn’t come on first thing in the morning the last two mornings, but works once I disconnect and reconnect it and then runs fine all day. Weirdly, the pressure hasn’t been dropping over the last couple of days and it seems pretty stable during the day, no idea why that would be. So from having a problem with pressure, I’ve gone to having a problem with the pump. Plan to do the boiler isolation test tonight, to see what impact that has.