I have a Saunier Duval THEMA F 23 E Combination boiler, it's about 8 years old. The water pressure gauge is nearly on the red markings 0.5 bar but when boiler fires the gauge goes to 1.5 bar.
1. Is this normal?
2. Does it need more water added?
3. Does this indicate there is air in the system?
Thank you for your help.
1. Is this normal?
2. Does it need more water added?
3. Does this indicate there is air in the system?
Thank you for your help.