Water for anti freeze concentrate

[Marke663]

Hello all

I have Meriva B A14NET

I just had to change thermostat due to the thermostat housing gasket blowing  and sending temp gauge up to 130

Hopefully, no damage to engine. I had a few questions resulting from this little job that hopefully someone can answer.

1. The  job was a bit fiddly to be honest and I was surprised that the gasket was removable and I could not find one and had to buy a cheapo? STARLINE complete housing from Eurocarparts at £55. Has anyone else found a thermostat housing gasket for sale? 

2. Does the Meriva B (mine is Exclusive AC) have a coolant level sensor? I got no  warning until I noticed temp gauge shoot up.

3. I’ve had car 9 years and when I do checks I always glance at expansion tank to see coolant level . However, it was only after this issue that I realised the tank has seperate compartments and  I have been checking (side nearest engine)  which seemed ok but  the other side was actually empty… is this correct?

4.. most import question now… what water should I use to mix with concentrate anti freeze? The manual says tap water but when googling some say distilled, some say deionised and other say tap water. I live in hard water area where taps , kettle and glass shower doors crud up with limescale VERY quickly. I don’t understand the chemistry behind the limescale build up, maybe a closed circuit like engine coolant won’t have a limescale build up? What water do you use? I’ve filled mine up with mix using tap water but am worrying I shouldn’t have.

thanks

[FRONTERATECH]

suggest distilled water you are using the red

 

no sensor on the tank on meriva B

 

Edited August 5 by FRONTERATECH
updated

[Marke663]

Thx for response. I guess I’ll have to replace it then. I also asked Vauxhall customer services and didn’t expect them to reply, hence posting here. Amazingly they replied very quickly. So, although manual says tap water they now advise me to use deionised or distilled. That’s cost me 3 bottles of red antifreeze concentrate:( They also told me there’s an outstanding safety recall on my 11 year old Meriva:)

As a matter of interest what site did you use to get that diagram?