Grohe Thermo Wireless Pump Shower

[Drak]

Hi

I'm about to install a grohe wireless shower pumped version. It's a gravity system, base unit to be fitted next to the hot cylinder in cupboard behind shower.

My question, can I run 15mm from the loft cold tank into the base unit or do I need to run most of it in 22mm, likewise 15 or22m for hot supply. Also Grohe have said there's no need to use a surrey flange, I can simply take the hot supply before it tees off any where else. Is this correct since I thought pumps needed a flange to stop air.

I'm no plumber but want to get it right first time.

 

[seco services]

these showers are totally different to your standard mixer and pump system.
we fit many of these, just run both feeds in 15mm. if your fitting any isolation valves fit full bore. we use lever valves for isolation valves.
no you don't need a surrey flange you can come off the hot supply pipe it don't affect these showers in any way.
if your taking it from the vertical hot supply make it the first tee off, if teeing off the horizontal pipe fit your tee pointing downwards.
you can always fit the system box in the loft if it's easyer long as it's not above the cws tank.

 

[Drak]

Thanks Seco. I want to connect on the horizontal, at the moment the horizontal leaves the cylinder and then tees off with 15mm to shower and 22mm to the rest of bathroom. Can I extend the existing 15mm?

Is it essential to point the tee downwards?