Megalife vented cylinder with secondary loop + shower pumps

[nigelmcl]

New to this forum business and would appreciate your opinions.
I am doing a new build in a rural area, I have a private water supply that is 400 Yards in 32mm blue pipe from the water meter (my water boundary). It supplies 30 litre per minute and fluctuates generally between 2.7 and 4.2 Bar. I say generally; on the odd occasion it is down to 2 bar.

Because of the fluctuation I have decided to stick with convention and opt for a 210 litre megalife and a loft tank rather than a mains megaflow on the basis that then I can choose the pressure that the showers run at (3 of them) rather than the water supplier. (It really is a tough choice, I just wonder/worry what will happen to mains pressure in 10 years when perhaps most of the country has mains fed hot water - don't want to get bogged down in that as another topic).

Anyway, the question. Can I have a hot water loop to the secondary return to give fairly instant hot at the taps and in addition add 3 bar pumps off of that loop to the showers.

Apologies in anvance, if it is stupid question. Hopefully get some sensible answers - thanks

 

[SimonG]

No. How you going to stop the secondary pump pumping over your hot water into the header tank. Just drop the secondary return.


Oh and welcome to the forum.

 

[Dotty]

Or, assuming you're G3, fit the UV and an accumulator.

 

[nigelmcl]

Thanks for the info guys - perhaps I should have phrased the question as "I want to run a DHW loop and also run shower pumps" using a 210l megalife (vented). I spoke with Sadie this morning and they said use the secondary return for the pumped loop and tee off the main outlet at the top of the tank for the shower pumps. Is it as simple as that? Is that where you were taking me SimonG?

 

[Megaflo-Experts]

Yes, that makes sense, but you need to ensure the pumps are fitted AFTER you have tee'd off from the secondary hot water loop, thereby pumping towards the shower outlets rather than around circulation the loop.

Thanks for the info guys - perhaps I should have phrased the question as "I want to run a DHW loop and also run shower pumps" using a 210l megalife (vented). I spoke with Sadie this morning and they said use the secondary return for the pumped loop and tee off the main outlet at the top of the tank for the shower pumps. Is it as simple as that? Is that where you were taking me SimonG?

 

[josh]

You can have open vent hot water with a secondary loop, just ensure the pump setting head does not exceed the head of the system. Have done them before and been fine, I to had that consumption of pumping over originally until came across a couple of existing systems with loops on open vent then at a hotel, a big hot water system with big flanged pump and all works well.
As said can't put the loop through the shower pump tho, would constantly run! Lol.