Hello,
I currently have an ancient Grant 70/90 with reilio burner running sealed and feeding a 250l unvented cylinder with 30tube solar for DHW, 3 small rads upstairs, 1 towel rail and ground floor UFH (150mm centres and Gypsum screed, tile floors) split into 7 zones, all hooked up through a Heatmiser UH1.
Heating a 90m sq bungalow with attic conversion, solid brick walls and no insulation in roof, (solid floor has 100mm PIR though) needless to say insulation would be best option to curb excessive oil use but as we could be doing with a new roof and render in the next few years, that = new warm roof and EWI to low U-value which is a few years off yet.
Winter sees us get through 500l of oil a month, Mrs at home with baby, id like to cut this (oil use! not the mrs and kids)...
I have been given a Warmflow 70 condensing boiler with only 6 months use
Whilst it should be more efficient than my old boiler its still going to suffer from short cycling due to UFH only needing low temp and oil not modulating.
I have found a 200l vented cylinder with solar and indirect coils for little outlay.
My thinking....
Connect UFH with the 200l tank (vented), heated from top down by the indirect coil to 40 or 50deg to minimise standing losses, 2 stats to control on/off. Or is it best to heat to normal temp of boiler and let the UFH manifold mix it down?
Solar linked in to buffer and swapped manually with a valve for summer/winter to help with space heating or DHW (could be automated to do either or both with right logic).
Boiler remains sealed and supplies the DHW coil, buffer tank coil and rads/towel rail direct.
I see this as giving quick heat up for the rads/towel rail/DHW coil (sealed to minimise corrosion in rads/boiler) and putting a large load to help stop cycling when UFH is required, corrosion should be less of an issue with the UFH, only metal component is the manifold and valves.
Heating the buffer top down should allow the UFH to draw warm water quicker than waiting for the full 200l to heat?
Would this work, if so how best to optimise for condensing operation?
Is it likely to save more than the £200 or so it could cost to implement (DIY, no changes to unvented cylinder required.)
Cheers for any advice.
I currently have an ancient Grant 70/90 with reilio burner running sealed and feeding a 250l unvented cylinder with 30tube solar for DHW, 3 small rads upstairs, 1 towel rail and ground floor UFH (150mm centres and Gypsum screed, tile floors) split into 7 zones, all hooked up through a Heatmiser UH1.
Heating a 90m sq bungalow with attic conversion, solid brick walls and no insulation in roof, (solid floor has 100mm PIR though) needless to say insulation would be best option to curb excessive oil use but as we could be doing with a new roof and render in the next few years, that = new warm roof and EWI to low U-value which is a few years off yet.
Winter sees us get through 500l of oil a month, Mrs at home with baby, id like to cut this (oil use! not the mrs and kids)...
I have been given a Warmflow 70 condensing boiler with only 6 months use
Whilst it should be more efficient than my old boiler its still going to suffer from short cycling due to UFH only needing low temp and oil not modulating.
I have found a 200l vented cylinder with solar and indirect coils for little outlay.
My thinking....
Connect UFH with the 200l tank (vented), heated from top down by the indirect coil to 40 or 50deg to minimise standing losses, 2 stats to control on/off. Or is it best to heat to normal temp of boiler and let the UFH manifold mix it down?
Solar linked in to buffer and swapped manually with a valve for summer/winter to help with space heating or DHW (could be automated to do either or both with right logic).
Boiler remains sealed and supplies the DHW coil, buffer tank coil and rads/towel rail direct.
I see this as giving quick heat up for the rads/towel rail/DHW coil (sealed to minimise corrosion in rads/boiler) and putting a large load to help stop cycling when UFH is required, corrosion should be less of an issue with the UFH, only metal component is the manifold and valves.
Heating the buffer top down should allow the UFH to draw warm water quicker than waiting for the full 200l to heat?
Would this work, if so how best to optimise for condensing operation?
Is it likely to save more than the £200 or so it could cost to implement (DIY, no changes to unvented cylinder required.)
Cheers for any advice.
