I am thinking of fitting a thermostatic mixer shower and have a combi boiler. The ones I have looked at say that if the mains pressure exceeds 5 bar then I would need to fit a drop tight pressure reducing valve to the mains feed. Is there any easy way to check my mains water pressure?
The only way to test water pressure is with a proper meter. However, it is unlikely that mains pressure will exceed 5 bar. Nearly all mains mixer showers are only rated up to this pressure but work fine on a combi without further pressure control.