Hi,
I'm trying to make a decision on these two system boilers which seem to be the most like for like compared to others. I've read up as much as I can on the forum before posting but can't come to a conclusion. I still need my heat loss calculations done first but I'm very confident that it will be low due to the recent upgrades on insulation and size of property, which is a 3 bed detached, approx 98 sqm. No UFH. Obviously if I am wrong after calculations then I would adjust Kw but I would still like to choose between these two manufactures.
I plan to do PDHW with a 150L indirect unvented cylinder. Still unsure if I'm going weather or load compensation as I've never had experiences with either of them.
I'm trying not to base everything just on specifications between them as customer support, parts availability and how they perform in the real world are also just as or if not more important. However, I only have online information available to me, so this was my result;
Viessmann 100w - 11kw
- Modulation down to 3.2kw
- PDHW & wifi App out of the box
- Choice of my own filter/deaerator
- Additional purchases for weather/load comp, outdoor sensor or Vitorol 100-E
- Support/parts availability seem a bit lacking and expensive
- 10 yr warranty as standard, 12 yr for £270 (with approved installer)
Current price approx £788
Vaillant ecotec plus 610 - 10kw
- Modulation down to 2.8kw
- PDHW requires VR71
- Additional purchases for wifi App requires myVaillant connect box
- Additional purchases for weather/load comp, Sensocomfort/Sensohome
- Support/parts availability seem decent but also can be expensive
- 7yr warranty as standard, 10yr warranty if Vaillant advanced filter pack used (with approved installer)
Current price approx £1224
150L indirect unvented cylinder
Either OSO DC or Vaillant Unistor
Clearly you get a lot more with the 100w for less and it definitely starts to get real pricey with the ecotec and it's additional extras. As stated earlier, I'm aware there are other factors to consider but this is obviously a one time, long time purchase so I'd rather just be happy during that period.
As for the cylinder, I wasn't sure if I should consider getting a heat pump variant. At this point it all became a bit overwhelming. Would it be 150L for 2/3 people but the ASHP equivalent is 180/210L? If so, are the costs of storing an extra 50L ish being and also being reheated quicker a significant extra running cost or not so much?
Where I was getting confused is with PDHW you get the benefit of quicker reheat times, so with an ASHP variant and basic logic, is that even faster?
I know there are many posts on which boiler to get, so I do appreciate that you had the patience to read another one. Thanks.
I'm trying to make a decision on these two system boilers which seem to be the most like for like compared to others. I've read up as much as I can on the forum before posting but can't come to a conclusion. I still need my heat loss calculations done first but I'm very confident that it will be low due to the recent upgrades on insulation and size of property, which is a 3 bed detached, approx 98 sqm. No UFH. Obviously if I am wrong after calculations then I would adjust Kw but I would still like to choose between these two manufactures.
I plan to do PDHW with a 150L indirect unvented cylinder. Still unsure if I'm going weather or load compensation as I've never had experiences with either of them.
I'm trying not to base everything just on specifications between them as customer support, parts availability and how they perform in the real world are also just as or if not more important. However, I only have online information available to me, so this was my result;
Viessmann 100w - 11kw
- Modulation down to 3.2kw
- PDHW & wifi App out of the box
- Choice of my own filter/deaerator
- Additional purchases for weather/load comp, outdoor sensor or Vitorol 100-E
- Support/parts availability seem a bit lacking and expensive
- 10 yr warranty as standard, 12 yr for £270 (with approved installer)
Current price approx £788
Vaillant ecotec plus 610 - 10kw
- Modulation down to 2.8kw
- PDHW requires VR71
- Additional purchases for wifi App requires myVaillant connect box
- Additional purchases for weather/load comp, Sensocomfort/Sensohome
- Support/parts availability seem decent but also can be expensive
- 7yr warranty as standard, 10yr warranty if Vaillant advanced filter pack used (with approved installer)
Current price approx £1224
150L indirect unvented cylinder
Either OSO DC or Vaillant Unistor
Clearly you get a lot more with the 100w for less and it definitely starts to get real pricey with the ecotec and it's additional extras. As stated earlier, I'm aware there are other factors to consider but this is obviously a one time, long time purchase so I'd rather just be happy during that period.
As for the cylinder, I wasn't sure if I should consider getting a heat pump variant. At this point it all became a bit overwhelming. Would it be 150L for 2/3 people but the ASHP equivalent is 180/210L? If so, are the costs of storing an extra 50L ish being and also being reheated quicker a significant extra running cost or not so much?
Where I was getting confused is with PDHW you get the benefit of quicker reheat times, so with an ASHP variant and basic logic, is that even faster?
I know there are many posts on which boiler to get, so I do appreciate that you had the patience to read another one. Thanks.
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