Santon Premierplus unvented hot water system — intermittent discharge

[Xerxes]

I have a Santon Premierplus unvented hot water system — Model number PP250B — which was installed in 2008.

The system provides DHW as intended.

The system has been serviced each year by a the plumber who installed it.

Before the last service the I noticed that the expansion valve of the cold water combination valve had operated.

I kept an eye on this. The discharge is intermittent. It can go for days without any discharge.

When the valve does discharge it reseats cleanly and does not drip.

On the scheduled service visit the plumber checked and topped up the charge pressure of the expansion vessel and carried out the other safety checks.

However the discharge problem occurred again a few days after his visit.

I’m curious to know why this intermittent discharge is happening as the plumber gave the system a clean bill of health.

I wonder if others have experienced this problem and if so what was the root cause and how did they cure it.

Thanking you in anticipation.

 

[Ermintrude]

The installer didnt pay enough attention! Get him back. Is he actually qualified?

 

[kirkgas]

First question, is the discharge hot or cold? I know you said from the cold, but then said combination valve, so not sure, That gives direction as to what's causing the problem

 

[Xerxes]

First question, is the discharge hot or cold? I know you said from the cold, but then said combination valve, so not sure, That gives direction as to what's causing the problem

The discharge is cold.

The combination valve has two separate parts. The first is to reduce the pressure of the mains water into the system to 3.8 Bar. The other section is to release the system pressure if exceeds 6 Bar. It is this part which is operating intermittently.

 

[Xerxes]

...Is he actually qualified?

He is properly qualified.

 

[Dotty]

Then let him deal with it. It's illegal for you to be touching it.

thread closed.