Replacement mixer shower

[Bigtree]

Hi all, I am looking at replacing a mixer shower in our bathroom and have confused myself

What am I best looking for in regards to flow and pressure?

They all seem soooo different?

5l at 0.1bar
4.5l at 0.5bar
Etc etc

Am I correct in thinking that the ‘higher litreage’ with the ‘lowest pressure’ will give the better performance?

 

[Deleted member 267285]

They’re different based on what type of pressure you have. Start by telling us your existing hot and cold water delivery, eg all mains pressure?

 

[Bigtree]

Hey, many thanks for the quick reply.

Yes, both direct from mains (hot through a Worcester Bosch Condenser Boiler)

I have no idea what my incoming mains pressure is though

 

[Deleted member 267285]

Hey, many thanks for the quick reply.

Yes, both direct from mains (hot through a Worcester Bosch Condenser Boiler)

I have no idea what my incoming mains pressure is though

You should have a minimum amount of pressure for the Combi to work, so probably at least half a bar (0.5 bar). The 0.1 bar and upwards to about 0.3 bar are for hot water cylinders where the pressure is relied upon gravity - from the shower head to the base of the cistern.

 

[Bigtree]

My boiler is set to 1 bar when cold. Minimum I think on the green gauge is 0.5 bar.
So, am I best avoiding the 0.1’s etc and go for a 0.5 plus?

Something like this perhaps?

Grohe Precision Flow Rear-Fed Exposed Chrome Thermostatic Shower Mixer Set - Screwfix

Order online at Screwfix.com. Thermostatic cartridge with wax thermo-element ensures instant water flow at desired temperature, keeping it constant irrespective of fluctuations in water pressure or supply. SafeStop limits water temperature to 38°C, with optional increase to 43°C, to reduce risk...

www.screwfix.com

 

[Deleted member 267285]

My boiler is set to 1 bar when cold. Minimum I think on the green gauge is 0.5 bar

That’s your central heating pressure - nothing to do with the incoming cold main. How fast can you fill a 1 litre receptacle?

 

[Bigtree]

Gotcha (doh, silly me)
I’m in bed right now but I’ll be sure to fill a 1litre jug in the morning and let you know.
Many thanks for your help, I genuinely appreciate it

 

[Bigtree]

Good morning. It takes 5 seconds to fill a 1 litre jug from the cold tap (in the kitchen)

 

[Deleted member 267285]

Good morning. It takes 5 seconds to fill a 1 litre jug from the cold tap (in the kitchen)

Pressure and flow rate is good then, so pick whichever takes your fancy.

 

[Bigtree]

Really, literally any, high or low?

I’m curious now if it took 10 seconds or 15……..what would my options have been?

 

[Deleted member 267285]

Really, literally any, high or low?

I’m curious now if it took 10 seconds or 15……..what would my options have been?

So you have approximately 12 litres per minute

10 seconds roughly 6 litres per minute and 15 seconds would be 4 litres per minute