At the moment I have pumped CH and what was gravity DHW but when the replac= ement boiler (Ideal Mexico Super 2) was fitted it made the DHW inefficient = due to the distance from the tank and the run vertually level across the le= ngth of the kitchen wall for about four meters before going up to the tank = in the bathroom above, so the plumber fitted a pump next to the tank to hel= p. It's been like this now for about six years.
Whilst doing another job I found that the heating pipes leave the boiler in= 22mm to the first radiator upstairs then all the rest are in 15mm so in th= e spring I plan on changing this to 22mm to all the radiators with 15mm tai= ls. Whilst doing this I thought about changing the system to a proper fully pum= ped system using two motorized valves and one pump.
What I was thinking of doing was keep the 28mm from the boiler and run this= to a pump then split to two motorized valves then carry on with the origin= al 28mm to tank because it will be a major job to remover the 28mm and repl= ace it with 22mm and from the other valve drop down to 22mm to join up with= the original CH piping. The fill and expansion I will move so they go dire= ct to the boiler on the old CH tapings as it shows on the boiler manual.
Could anybody tell me if this is doable, or a better solution?