The burner will also cycle “off” for longer periods so any reduction in return temps would be a moot point.
Single pipe central heating systems - hybrid options?
- Thread starter dhutch
- Start date
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Make and model of boiler?
Indeed, you would get lower return temps and better condensing, but a the cost of cooler rads at the end and so lower total output. It would also have make balancing the five 22mm loops against each other even more challenging.
Viessmann Vitodens 100 35kW system boiler, believed new in 2012.
Daniel
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If you are going to convert the complete installation to two-pipe, the current radiator sizes will all be wrong for two reasons:
- The old system will have been designed for an 11C (Actually 20F in 1965) drop between flow and return at the boiler. The Viessmann expects a 20C drop.
- The current radiators will have been sized for a drop of about 5C across each one with a reducing flow temperature as you get further from the boiler.
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Hi, yes obviously the sizing of the original rads would likely have been very different from that of what we need now. However of the 18 or so rads only two are the originals from circa 1965, and the various replacements appear to have been done one or two at a time in a seemly random fashion with little understanding of what they are attached to.
Some of these will be replaced, other however are reasonably new and are well speced for the new system or close enough, so are staying.
As far as I know we do not have the sensor for the boiler to run in compensating mode. It's running off an old Danfoss 102e7 with no thermostat. So the cintrilcon will also be replaced with something like a Drayton MiTime or Wiser.
Daniel
Some of these will be replaced, other however are reasonably new and are well speced for the new system or close enough, so are staying.
As far as I know we do not have the sensor for the boiler to run in compensating mode. It's running off an old Danfoss 102e7 with no thermostat. So the cintrilcon will also be replaced with something like a Drayton MiTime or Wiser.
Daniel
The MiTimer has been discontinued by Drayton.
The Wiser can provide Opentherm control, but you need to fit the Opentherm Module to the 100-W.
Have you considered Viessmann's own controls, or are you looking for something Smarter, i.e internet based?
The Wiser can provide Opentherm control, but you need to fit the Opentherm Module to the 100-W.
Have you considered Viessmann's own controls, or are you looking for something Smarter, i.e internet based?
I thought it was just the MiGenie that have been discontinued, in favour of the 'Wiser' system?
The boiler isn't new, installed 2012 as far as we know, so whole the manual talks about compensating I don't know if it has opentherm. It's got 'mechanical' knobs for water and heating temperature which the later ones appear to have lost for a touch panel.
Didn't even know Viessmann did controllers. In one way it might be fun to be able to turn heating on remotely occasionally, but basically I would much rather program it with buttons on the wall than have something app/wifi enabled.
###
In other news the plaster was dry enough last night to turn on the lounge radiator on the new droppers from the converted two-pipe first floor system (only rear of house completed yet) and compared to the other rad in the same room still on the single-pipe is so much hotter. The whole room is noticanoti hotter and you can't put the back of your hand on it for more than a second, Vs being warm but not hot. Obviously when all the rads are getting upto around boiler output temperature we can turn the boiler temp down from nearly max to something more like 65-70c and or compensated control.
Exciting times! Might actually be warm in the house next winter.
Daniel
The boiler isn't new, installed 2012 as far as we know, so whole the manual talks about compensating I don't know if it has opentherm. It's got 'mechanical' knobs for water and heating temperature which the later ones appear to have lost for a touch panel.
Didn't even know Viessmann did controllers. In one way it might be fun to be able to turn heating on remotely occasionally, but basically I would much rather program it with buttons on the wall than have something app/wifi enabled.
###
In other news the plaster was dry enough last night to turn on the lounge radiator on the new droppers from the converted two-pipe first floor system (only rear of house completed yet) and compared to the other rad in the same room still on the single-pipe is so much hotter. The whole room is noticanoti hotter and you can't put the back of your hand on it for more than a second, Vs being warm but not hot. Obviously when all the rads are getting upto around boiler output temperature we can turn the boiler temp down from nearly max to something more like 65-70c and or compensated control.
Exciting times! Might actually be warm in the house next winter.
Daniel
According to Drayton's website, all "Mi" products are discontinued; i.e MiGenie, MiStat, MiTime RF and MiTime.
Seems your right, they are on there (and listed for sale at numerous outlets) only last week.
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