Reducing boiler water pressure

[Richard Cobley]

I want to reduce the pressure in to my combi boiler (Ariston Genus 23/27 MFFI). I've identified the domesic cold water inlet pipe but I'm not sure what to do. There is a screw with a large square blue plastic head, just as the pipe goes in to the elbow that connects under the boiler, which is turned clockwise as far as it will go. On the elbow there is a plain screw valve.

Are any of these suitable for controlling flow, or should I look further back up the cold water line?

The reason I want to reduce the pressure is that my shower lets water through at a reasonable rate, and now that winter's here the boiler can't get the water hot enough (the shower is off the boiler). If I flush the toilet at the same time though, the slight reduction in pressure means that the boiler copes and the water is a lovely temperature.

I don't want to keep flushing the toilet when I'm showering so advice gratefully received :)

Richard.

[Christian McArdle]

You'll want to reduce the flow rate (not the pressure) as late as possible, so each individual outlet can be tuned to the boiler's maximum output. Your shower may already have an isolation valve that could be used for the purpose.

Christian.

[Richard Cobley]

Fair point, but the shower has been built in to the wall. It looks like a corner has been built out slightly (and tiled over) and all the pipes are behind it, including any valves. The pipes for the sink come from this cavity and they have through valves closer to the sink, but alas anything for the shower involves knocking a wall down...

The pipes coming from the boiler aren't much better they drop straight behind a fitted kitchen and then disappear behind the wall.

Is reducing the boiler pressure really not a good idea then?

Cheers,

Rich.

[Fred]

My boiler has a valve to reduce the flow rate. It's Worcester Bosch 40 Greenstar, maybe yours has that too?

Fred

[adder]

This sounds like a pressure reducing valve - some are adjustable some aren't. Should have bought a higher spec combi! Can't you adjust the flow at the shower controls or is it only on/off?