Just replaced Mira event xs with a new one. - less pressure and heat?

[wolfytom]

As per the title - I changed nothing else and just replaced one with another.
To get the shower hot it has to be permanently pushed up to Max whereas before it was fine at 5 and the pressure is significantly lower.

I noticed the shower design had changed inside. Instead of a mixer bottle it now just has a tube.

I have noticed that the hot water flow through the bathroom sink appears to be a little bit stuttery and the shower sound suggests its having a similar problem.
Any ideas?

 

[PlumbBobBob]

how did you isolate the water to change the unit?

 

[wolfytom]

how did you isolate the water to change the unit?

I turned off the big red isolating taps that I fitted on the hot and cold feeds from both the cold tank and cylinder.

 

[Chalked]

Are these restricted to 12 litre/ min?

 

[wolfytom]

The taps were fitted when I fitted the original event xs about 8 yes ago. It lasted so well I bought another!
We never had a problem with pressure or temp until I fitted the new unit. I think the event does 16 a minute

 

[gassafe]

Debris in inlet filters or partially shut gate valve or restriction maybe?

 

[wolfytom]

Thanks gassafe and others
Are the big red taps the gate valves? If so they are completely open.
Debris? I'll check but the unit is brand new?
Where else might I find restrictions?

I have 15mm pipes feeding the shower - I've read that 22mm would be better but the olkd one always worked fine. I suspect that the new internal design has affected performance. The big bottle where the hot and cold got mixed is now just a narrow tube. What do you think?

 

[Plumbstar Tom]

Check what flow your getting compared to what the manufacturers website says you should be getting

 

[wolfytom]

Sounds like a great idea - how do I do that? Measure the water over a minute?
Mira have suggested I 'commission' following the instructions in manual.

 

[Chalked]

Says 16 l/min flow.

 

[PlumbBobBob]

did you not commission it then?

 

[wolfytom]

There are 2 forms of commissioning . General and Max Temp. I didn't have to do latter with first unit. Just done it on new unit. Increased temp but that reduces pressure...