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hotdogharry

Hi
I have a new Worcester Greenstar i combi condensing boiler and im a little confused!!!
I have central heating temp set to 60 degrees C and water temp set to 50 degrees C. Also using Danfloss thermostat (set to 21 degrees ) I have load compensation set to 3 cycles per hour.
What is confusing me is the tempeature the boiler shows pre and during load compensation cycle firing up. Pre it shows around 40 degrees (no heating/water symbol) and when firing up it goes up to around 48/52 degrees (radiator symbol shows) Why is this not the 60 degrees as set for central heating?
Any advice greatly appreciated!!!
 
Will take a bit to get upto temp eg when the rooms warm
this happens when room is already up to temp!!! heating currently on 24/7. Cant see how if flow temp is set to 60 why its only heating it to 48/52 degrees.Also is 50 degrees water temp hot enough to kill bacteria from taps?
 
With your load compensation your stat will be regulating the temp of the boiler so because your rooms are nearing temp your stat will be telling the boiler that full flow temp won't be required. At least that's my understanding of how load compensation works.
 
  • Agree
Reactions: SJB060685
Your first port of call should be your installer. At the completion of comissioning they should have given you a 'Benchmark' statement, the instruction books and clearly explained to you how the system operates and how to use the controls. 'Professional courtesy' dictates that I advise you give them a reasonable chance to help you first.

If you don't get anywhere with your installer, you'll need to provide more details about the system (boiler model, controls, numbers of radiators, zoning, room programmer/thermostat model, etc.) and a minute-by-minute description of how it is behaving for us to be able to help.
 
With your load compensation your stat will be regulating the temp of the boiler so because your rooms are nearing temp your stat will be telling the boiler that full flow temp won't be required. At least that's my understanding of how load compensation works.
thanks for that does seem to make sense but still not sure and its confusing for the laymen!!! Any engineers out there can you confirm this?
Also for boiler to condense I believe flow return temp has to be around 55 degrees How on earth can I know this?
Also is 50 degrees water temp hot enough to kill bacteria from taps?
 
thanks for that does seem to make sense but still not sure and its confusing for the laymen!!! Any engineers out there can you confirm this?

It's an accurate description of what 'load compensation' refers to but I'm not convinced that it's applicable to your system and circumstances. It's not normally specified by a number of 'cycles' either. Without knowing which models of boiler and controls you have it's difficult to be specific.
 
50° isn't technically hot enough to kill bacteria (legionella) in the water supply but because the water isn't stored the risk is very minimal so I wouldn't worry about it.
 
Your first port of call should be your installer. At the completion of comissioning they should have given you a 'Benchmark' statement, the instruction books and clearly explained to you how the system operates and how to use the controls. 'Professional courtesy' dictates that I advise you give them a reasonable chance to help you first.

If you don't get anywhere with your installer, you'll need to provide more details about the system (boiler model, controls, numbers of radiators, zoning, room programmer/thermostat model, etc.) and a minute-by-minute description of how it is behaving for us to be able to help.
its a worcester combi condensing greenstar 25i, terrace house with 5 radiators 2 up three down ( all except downstairs bathroom pipes go up first then down to kitchen/living room) using a Danfoss TP5000 Si programmable thermostat. Keeps constant temperature in living room where thermostat is curently using load compensation setting on thermostat at 3 cycles per hour Just wondered when boiler fires up it only shows heating temp at 48/52 degrees but have flow temp set at 60 degrees
 
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