Hi, I was wondering if it would be a good idea to run the DHW pipe under the ground before reaching taps and Boiler), and run this looped
plastic pipe in a 2 meter deep x 50 meter long trench underground. Then this pipe would deliver water to the oil boiler (and hot taps).
I would be thinking of just depending on the present gravity (attic tank - about 13-15 meters higher than proposed looped pipe in trench) - to circulate the water. Would this be feasible as a way of pre-heating the water before it enters the boiler? Though I realise that the water tank in the boiler would not increase in temperature until enough "new" underground water runs into it, once the taps are turned on. I am trying to think of some way of
avoiding the high cost of a heat pump. Thank you.