Hi,
I need to replace the boiler in our house as it has all but packed in. I think we currently have an unvented setup. Looking to replace with a combi boiler, due to bathroom extension and loft conversion.
The combi boilers of interest are the Viessmann 333-F (Ws3c or Wr3c models) or the Worcester Bosch Greenstar Highflow 550CDi. All are floorstanding and have water storage built-in. The V-333 models have ws3c=86L and wr3c=130L with 26kwh DHW output and the WB-550 has 51L with 42kwh.
My question is, should I go for the higher water storage boiler with the lower DHW output, i.e. V-333, because more water is available immediately or should I opt for higher DHW outout and lower water storage, i.e. WB-550, because it can provide hot water faster once store has run out.
Also, out of the 2 Viessmanns which one is better recommended, the 86L or 130L model. The latter has some sort of indirect heating element in tank so hard water and limescale don't affect it as much. Does that mean because it's indirect it won't heat water as quickly?
Finally, is 26kwh output enough to cope with heating and showering at the same time, or do I need 42kwh?
Thanks for any help provided.
Sat
I need to replace the boiler in our house as it has all but packed in. I think we currently have an unvented setup. Looking to replace with a combi boiler, due to bathroom extension and loft conversion.
The combi boilers of interest are the Viessmann 333-F (Ws3c or Wr3c models) or the Worcester Bosch Greenstar Highflow 550CDi. All are floorstanding and have water storage built-in. The V-333 models have ws3c=86L and wr3c=130L with 26kwh DHW output and the WB-550 has 51L with 42kwh.
My question is, should I go for the higher water storage boiler with the lower DHW output, i.e. V-333, because more water is available immediately or should I opt for higher DHW outout and lower water storage, i.e. WB-550, because it can provide hot water faster once store has run out.
Also, out of the 2 Viessmanns which one is better recommended, the 86L or 130L model. The latter has some sort of indirect heating element in tank so hard water and limescale don't affect it as much. Does that mean because it's indirect it won't heat water as quickly?
Finally, is 26kwh output enough to cope with heating and showering at the same time, or do I need 42kwh?
Thanks for any help provided.
Sat
