Worcester 27 Ri 27 kW
Grundfos UPS3
3 port valve with bypass to 3 towel rails (one with TRV)
Hot water cylinder with 2 coils (solar thermal to the bottom)
Cyclinder stat (set just over 60 Deg C)
Hive controls
Shower pump taking off about 2/3 from top of cylinder.
hi all,
have a condensing boiler put in to replace a very old feroli non-condensing. New pump. new cylinder (180 L I think. Same size as previous one).
Heating is ok but have a question about getting enough HW and getting to temp in the cylinder.
Running the boiler on HW only seems to cause the boiler to peg out every 5 mins. Take 5 mins to cool down and go again. End result is never really get to a good temperature and feels like it is only the top of the cylinder that gets hot so when that “layer” is used up it gets freezing cold.
No idea how you could get the whole cylinder to 60 and hold it there for an hour to kill all the bugs.
feels like the boiler doesn’t like getting too hot so when the return temp gets warm, and there is little flow as it’s just around the hot water circuit, the internals get too hot and it trip.
as it continues to circulate it does cool itself down to fire again but in the process it is taking heat OUT of the cylinder to push it out of the towel rails or flue. So 1 step forward, 1 step back!
the only two controls there seem to be the pump setting on the USP3 and the unmarked heat setting dial on the boiler. I have some temp probes set up on the inlet and outlet copper pipes on the boiler and cylinder to give me a rough I idea of the temp. I can get the boiler to output at about 62 max and once the return gets to about 48 it will trip off. At the cylinder it is a solid 60+ on the inlet (64-ish. May have that probe shielded better than the boiler one) and 50 on the outlet.
the outlet of the cylinder sits just above the stat placement in the cylinder which is about a third up from the bottom.
how can I set up to make and hold enough hw??
Grundfos UPS3
3 port valve with bypass to 3 towel rails (one with TRV)
Hot water cylinder with 2 coils (solar thermal to the bottom)
Cyclinder stat (set just over 60 Deg C)
Hive controls
Shower pump taking off about 2/3 from top of cylinder.
hi all,
have a condensing boiler put in to replace a very old feroli non-condensing. New pump. new cylinder (180 L I think. Same size as previous one).
Heating is ok but have a question about getting enough HW and getting to temp in the cylinder.
Running the boiler on HW only seems to cause the boiler to peg out every 5 mins. Take 5 mins to cool down and go again. End result is never really get to a good temperature and feels like it is only the top of the cylinder that gets hot so when that “layer” is used up it gets freezing cold.
No idea how you could get the whole cylinder to 60 and hold it there for an hour to kill all the bugs.
feels like the boiler doesn’t like getting too hot so when the return temp gets warm, and there is little flow as it’s just around the hot water circuit, the internals get too hot and it trip.
as it continues to circulate it does cool itself down to fire again but in the process it is taking heat OUT of the cylinder to push it out of the towel rails or flue. So 1 step forward, 1 step back!
the only two controls there seem to be the pump setting on the USP3 and the unmarked heat setting dial on the boiler. I have some temp probes set up on the inlet and outlet copper pipes on the boiler and cylinder to give me a rough I idea of the temp. I can get the boiler to output at about 62 max and once the return gets to about 48 it will trip off. At the cylinder it is a solid 60+ on the inlet (64-ish. May have that probe shielded better than the boiler one) and 50 on the outlet.
the outlet of the cylinder sits just above the stat placement in the cylinder which is about a third up from the bottom.
how can I set up to make and hold enough hw??
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