Cold water tank capacity v Power shower

[rubble2]

Hi,

We currently have a shower in the ensuite which is fed via a double ended pump in the airing cupboard - this works well, no problems in the 12 months that we have been here.

I am know looking at putting a second shower over the bath in the main bathroom and bearing in mind the need for a pump I have been looking at a power shower (mira vigour) from Toolstation. Looking at the installation instructions prior to purchase it states that the minimum capacity for the cold water storage tank should be 230 litres.

I have just checked in the loft and our tank holds 114 litres. Given that the existing shower works well using what is a fairly beefy double ended pump I would be surprised if the weedy little pump in the power shower case can dish out anything like the same throughput (obviously won't be using both showers together).

Is this likely to cause a 'real world' problem? or is it Mira being over cautious with its recommendations?

Thanks

 

[Madrab]

Most recommendations for a pumped supply would be a 50Gal cold water cistern, to ensure neither the cold water nor hot water, that is fed by the same cistern, runs dry. If it does the pump(s) could be damaged.

That being said it comes to to actual use and if you don't run out of water using the twin pump then chances are you wouldn't using the power shower.

 

[rubble2]

Thanks for the reply. I have just measured the throughput of the existing shower at 17ltr/min. So I think I will be ok fitting a 14ltr/min Mira power shower.

 

[ianmcd]

yes but if you have both running at the same time you will only get less than 4 minutes of showering, if you only use one at a time you should be OK