Jim1234

The buffering would be in an unvented cylinder. i looked at the maxipod but all open vent and I have no option for this in the house

Weather compensation on an oil boiler?

So a thermal store means I need to heat water to 70deg to get hot water plus I would have no storage. i also struggled to find an unvented thermal store. If my calcs are right at max demand the flow rate will be 14.45 litres/min. with a return temperature of 25deg and flow temp out of the coil at 55deg and a mixed flow of 40deg I would need the cylinder to heat 7.2 litres/min from 25 deg to 55 deg. at a 35deg mixed temp I would need 45deg from the coil at 7.2 litres/min

Total ufh load 8kw across 20 loops ufh flow 35 return 25 if the top coil was rated at 40kw based on a 80deg how would I work this back to know if it would work with a 60deg storage temp

Hi John, I believe on initial start up the ufh will strip all domestic hot water though when up to temperature though I expect this to be ok when running. The boiler will be controlled through the cylinder stat to keep the domestic hot water up to temperature 24/7 As for coil placement I was thinking boiler coil at the bottom of the cylinder to help with de stratification and then a high gain could towards the top. with blending on the flow only the heat required to bring return up 10deg will be extracted from the cylinder. I know someday I may have to go heat pump but I don’t believe they are the answer just yet. oil boilers are simple and work compared to heat pumps. Thanks

Hi, I’m new to this forum and looking some advice for a new build installation. I am considering plumbing my ufh flow and return into a secondary coil in my unvented cylinder to heat my house, rather than directly into the boiler flow and return. The theory is that the oil boiler will heat the domestic hot water and I will extract the heat from the cylinder using a pump and blending valve. I see a number of benefits in this type of system such as: - flow temperature to ufh manifolds at the correct temperature rather than 70deg from the boiler and mixing down to 35deg. -no short cycling of boiler -zones can be heated individually without boiler having to fire -hot water can be possibly stored at a lover temperature and boosted to over 60deg once a week for legionella purposes -storage of hot water in summer months unlike a thermal store which require higher temps to ensure hot water production all year Rough schematic attached Anyone ever done this before or be able to provide some advice. Thanks