shower pump off fortic cylinder

[mah]

hi all.im new to this, im only a apprentice and found this site to be a god send. i was wandering could you put a shower pump running off a fortic cylinder,say the pumps producing 15l/m and you sized the pipework from the mains to the fortic with a 3/4 inch float valve producing more or the same flow rate, can this be achieved. any reply would help thanks

 

[ChrisR]

In principle, yes.
A 3/4" BS1212 high pressure (9.5mm orifice) float operated valve gives a pressure drop of 1.5 metres at 28 l/min, which isn't a lot.

You also have to work out whether you're going to have problems sucking air down the vent pipe. Depends how you connect the hw feed to the pump. You get very little static head with a Fortic, so if the level of water in the vent gets sucked down far , you're in trubble. So guesstimate the effective length /diameter of the feed pipe from the cistern to the cylinder, and see what the pressure drop in it will be at the flow rate you need.
Having checked the figures, it's close.

 

[mah]

thanks chris for the reply

 

[Nige F]

How long is the arm+float of the 3/4 inch valve ..........longer than 450mm (dia. of fortic) ........you used to be able to get fortics with larger capacity cold sections........some even larger than the hot section