Getting thread back on track, so I've been given the job so looking forward to this one.
ive specd it up on 2 Worcester CDI 30kw system boilers with 2 unvented 250L solar cylinders (solar added at a later date) I'm going with the plate heat exchanger to separate the existing heating from the sealed new side which will heat the cylinders & the PHE on a sealed system using the boilers (swep B28 or B56 I'm looking at, anyone used them ?) internal pumps. The heating pump is staying (large Wilo) & will be connected to the O/Vside of the PHE. I'll be power flushing the 3 heating zones & running a magnacleanse. So I'm hoping once the existing setup is flushed / treated I should be able to connect the heat exchanger onto the pump & set up the wiring. Any advice on the wiring regarding relays etc much appreciated. Existing zone valves are 1"1/4, 1"1/2 & 2" iron connections & I'd like to be able to control each zone individually.
The only thing nagging me now is going unvented on the hot water, I'm replacing a horizontal calorofier with the 2 cylinders picking up the secondary return, again bit concerned about the pressure so still might leave the h/ water vented.
Comments welcome
Trev