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No i gave a rule of thumb HVAC calculation that is proven for all commercial appliacations and is deemed to be far to high for domestic standards build to current regulations.
Basic principles would suggest that if the op actually needs more than 100w/sqm then ufh isnt the best option.secondly id assume that the heatloss calc is massively inaccurate.
most systems we design run with water temp between 45 -60 acheiveing floor temps no greater than 30 with an average room temp at 21. assume 8deg diff between flow and return.
in practice that means to acheive the ops original 200w/m you would have a room temp of 20,flow temp of 55,100mm spaces, bare concrete,a floor temp of 38 and still not acheiving 200w/m.
what ufh companies say is they can acheive 100w/m not to design at this figure.
100mm spacing is normally only needed for low temp inputs ie ashp etc rather than gas/oil fired.
personally we'd be using 18/22 ufh products.
have seen,fitted and designed systems that run 12 ports easily and competently over 100m loops with no adverse effects.thats not to say youve seen some that dont, but.same can be said that ive seen plenty of small systems that dont work.
as for cross connecting thats each to there own,personally i dont like it,id much rather have even loop sizes for easier balancing.
based on the ops revised figure of 5000watts
it would be room temp 20,flow temp55,floor temp30,thick wood coverings,200mm spacings.15mm pipe.250m pipe.
No i gave a rule of thumb HVAC calculation that is proven for all commercial appliacations and is deemed to be far to high for domestic standards build to current regulations.
Basic principles would suggest that if the op actually needs more than 100w/sqm then ufh isnt the best option.secondly id assume that the heatloss calc is massively inaccurate.
most systems we design run with water temp between 45 -60 acheiveing floor temps no greater than 30 with an average room temp at 21. assume 8deg diff between flow and return.
in practice that means to acheive the ops original 200w/m you would have a room temp of 20,flow temp of 55,100mm spaces, bare concrete,a floor temp of 38 and still not acheiving 200w/m.
what ufh companies say is they can acheive 100w/m not to design at this figure.
100mm spacing is normally only needed for low temp inputs ie ashp etc rather than gas/oil fired.
personally we'd be using 18/22 ufh products.
have seen,fitted and designed systems that run 12 ports easily and competently over 100m loops with no adverse effects.thats not to say youve seen some that dont, but.same can be said that ive seen plenty of small systems that dont work.
as for cross connecting thats each to there own,personally i dont like it,id much rather have even loop sizes for easier balancing.
based on the ops revised figure of 5000watts
it would be room temp 20,flow temp55,floor temp30,thick wood coverings,200mm spacings.15mm pipe.250m pipe.