ChatterBank11 mins ago
Pressure too high on gauge of combi boiler
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You opened the top up valve too quickly and let too much mains pressure water into the closed system. Your mains water pressure must be 2.5 bar or more. As above reply, the best way is to let a little water out of one of the rads to reduce the pressure again. It is unlikely to do any immediate harm, but you should do it because the system is designed to work at 2.5 bar and you are stressing the internal components.
The reply above that suggests leaving it alone is ill-informed. It is true that combis have a pressure-relieving circuit. Depending on the system design it is usually set around the 6 bar mark. But this is designed the stop the thing blowing up under fault conditions - it doesn't mean that it is alright.
Well to come to the point I rang ARISTOPN TECHNICAL SUPPORT AND THE STEPS AS BELOW.
1. Switch off the power ro Boiler
2. Drain some of the water till the guage registers "0" on the boiler guage
3. At the back of the boiler where the flue comes out, there a metal ballaon ball behind the boiler with a bike pump screew
4. unscrew the cap, place a biycele pump, pump it till the pressure is 1 mm bar
5. Measure the pressure where you place the pump.
6. Do the pressure and measure the pressure at intervals etc
7. Replace the cap and refill the boiler and switch the power on.
8. please note, do not use motorised pump. it will also be better if you buy a pressure meter guage which registers not more than 5 bar (Halford or carprts shops).
Good luck, as am going to do my agian today
Do it gradually getting someone to check pressure at boiler when you are letting water out.
At 3 bar the safety pressure release valve is ready to operate to vent water outside.
If you have it at 1.5bar when operating it may rise to 2 bar max.
If it keeps rising after draining water out you may have a faulty diaphram in your expantion tank along water to bypass and repressure system