Shower pressure with a combi boiler is excellent since it is mains pressure. The only time this won't be the case is if the boiler is not powerful enough and the flow must be adjusted down (manually or automatically) to maintain sufficient temperature. You can't normally add a pump to a combi boiler and you wouldn't normally need to. Occasionally, mains pressure is too low for this setup to work well. The shower will also be impacted if anyone else draw hot water and exceeds the ability of the boiler to heat sufficient water to the set temperature. The type of shower you should install will automatically maintain the mix of hot and cold and you will experience a drop in shower pressure if this happens. Combi showers are basically just great if there's only one of them at once. It is difficult to compare them to a cylinder/pump combination. Pressure is great but flow rate can be limited, while the opposite tends to be true from a cylinder. Usually the pressure will exceed that from a 1.5bar pump but the maximum flow rate will not be as high as some power showers.
Electric showers are .. well lets' just say crap and leave it at that. No, let's not leave it at that. They're not only crap but they're expensive and nobody in their right mind should have one if they have a combi boiler.
Electric showers are .. well lets' just say crap and leave it at that. No, let's not leave it at that. They're not only crap but they're expensive and nobody in their right mind should have one if they have a combi boiler.
