Ideal Isar He24 Expansion Vessel

[SirGalahad]

The existing boiler is a Ideal isar He24 been in for nearly 9 years. Had 2 issues with it - first was some leak, the second was the expansion vessel failed so they fitted an external expansion vessel as the pressure kept on falling below 1 bar. The boiler was operating fine, it's when I came to clean some dirt from it did I look at the pressure gauge.

I was told by the engineer fitting the expansion vessel even though the pressure falls below a bar again as I have a radiator one floor above in attic not to worry. So looked at it again and the pressure is about 0.5 bar but boiler has been operating fine.

So should I worry or is this normal?

 

[ianmcd]

why dont you just top the pressure up ?

 

[SirGalahad]

why dont you just top the pressure up ?

I have topped the pressure up. But isn't topping up the system every so often letting new water into the system which will increase corrosion?

 

[ianmcd]

yes it does but you still have to top it up every now and then even though there is no leak what time scale are you talking about between replacement expansion vessel being fitted and you noticing the pressure drop ?

 

[SirGalahad]

yes it does but you still have to top it up every now and then even though there is no leak what time scale are you talking about between replacement expansion vessel being fitted and you noticing the pressure drop ?

I would say expansion vessel was fitted in April, then I noticed the pressure had dropped in June to 0.25 then I topped up and now again it dropped to 0.5 just recently. Now I have topped up a week ago and its about 0.8.

As I mentioned not had problems so that's why I am confused.

 

[ianmcd]

doesnt really sound as though you have much of a problem to be honest, the pressure showing on the guage will alter slightly when the boiler is running as the pump will affect the reading some it increases some it decreases and will fluctuate when the boiler is hot from cold but not by too much about 0.2 Bar is normal but have seen larger differentials, set it between 1.0 and 1.5 Bar when the system is cold and see how long it takes to move but compare apples with apples compare what the guage is saying again when the system is cold and the pump is not running , as I said I dont think you actually have a problem

 

[SirGalahad]

doesnt really sound as though you have much of a problem to be honest, the pressure showing on the guage will alter slightly when the boiler is running as the pump will affect the reading some it increases some it decreases and will fluctuate when the boiler is hot from cold but not by too much about 0.2 Bar is normal but have seen larger differentials, set it between 1.0 and 1.5 Bar when the system is cold and see how long it takes to move but compare apples with apples compare what the guage is saying again when the system is cold and the pump is not running , as I said I dont think you actually have a problem

Ian

Thanks for the advice. But can you clarify the plumbers point which was for this boiler as I had a radiator on the floor above then the pressure wasn't really an issue even though it may drop to 0.2 bars. The boiler has been operating fine but was just wondering about it.

 

[Terrywookfit]

I would be more concerned that it was an "Eyesore".
A slight pressure fluctuation is the least of your worries !!

 

[ianmcd]

Dont know what your plumber was thinking about having a Radiator higher than the boiler, yes it is not a good idea to have the boiler at the highest point in the system, i.e. in the loft , but having a radiator higher than the boiler wont stop pressure loss if you have a problem

 

[SirGalahad]

Just one more point. Thanks again Ian and terry for your input if I do get a new boiler fitted - current one is 9 years old in January I keep getting told different things when it comes to flushing the system.

One plumber said just put in an inhibitor as a power flush is a waste of time and can cause more damage than they attempt to fix, and the other said new boilers with their filters you need a full powerflush.

 

[ianmcd]

All depends on the system but be aware that if you are changing the boiler because of pressure loss if you actually have a pressure loss problem there is a good chance that it is on your system and not the boiler so you could put a new boiler in every day but the problem would still be there , I still think that upi dont have a problem though