Unistor cylinder or other for a Vaillant System

[andyman22]

Hi, we're looking to have an unvented cylinder installed and have been recommended a Unistor (as we have a Vaillant system boiler). I believe that all this can be controlled over e-bus, but I'm unsure what the advantage of this would be? Another recommendation had been an OSO Delta cylinder which has just been released which seems to have far better thermal insulation than nearly any other product out there (ERP A). Could this be a better option, or is their unseen advantages to an ebus controlled unistor...?

Cheers.

 

[fezster]

One of the major advantages (which I discovered after fitting a Megaflo with my Vaillant boiler) is that the Unistor can automatically adjust the temperature of the boiler when calling for HW. This means your heating could run at a much cooler 60 - 70 degrees (or less if you have UFH and/or a weather compensator), but when the cylinder calls for heat, it will ramp it up to 80 degrees.

 

[simond]

The disadvantage with eBus are the controls are a complete PIA to use.

You can run an OSO or virtually any unvented via Vaillant eBus. In my opinion ACV make the best cylinders, but they are not cheap.

 

[andyman22]

One of the major advantages (which I discovered after fitting a Megaflo with my Vaillant boiler) is that the Unistor can automatically adjust the temperature of the boiler when calling for HW. This means your heating could run at a much cooler 60 - 70 degrees (or less if you have UFH and/or a weather compensator), but when the cylinder calls for heat, it will ramp it up to 80 degrees.

Would the boiler not always ramp up to full if the call for heat is for the DHW as it would look at flow temp? Or have you got the boiler output reduced?

 

[andyman22]

The disadvantage with eBus are the controls are a complete PIA to use.

You can run an OSO or virtually any unvented via Vaillant eBus. In my opinion ACV make the best cylinders, but they are not cheap.

Thanks. Running a third party off the eBus NTC, would this still give an accurate temp reading (as in would it be in the expected height on the cylinder)?

 

[andyman22]

Could anyone tell me if a Unistor 260 is in a utility room, is it likely to give off a lot of heat and make a small utility room (2m x 2m) unbearably hot? Never had a unvented cylinder before so unsure how much heat is lost by them in real terms.

 

[muggles]

They lose naff all, you'll hardly notice a difference

 

[andyman22]

Great, thanks.