What water and overnight set-back temperatures do you use?
The title says it all, really.
What temperature do you have your DHW cylinder set to? Are you using open vent, sealed or pressurised?
What temperature do you have your CH overnight set-back set to?
Last edited by dty; 9th February 2017 at 10:58 PM.
I have an unvented OSO 250l cylinder. My HW is set to 62C with a differential of 7C. Through experiment, I have found that this temperature range suits an old thermostatic shower. HW is timed to come on at 0700-0900 and 1630 - 2000. During the summer, with a gas hob, I use about 1 cubic metre of gas a day.Originally Posted by dty
Thanks HenGus. I've just clarified the second question, which was about CH, not DHW.
I'm using over 25 cubic metres a day at the moment! You can see why I'm interested in this stuff!
I have a Megaflow 250L unvented cylinder and set DHW at 60C with a differential of 5C. All my CH temps are set at 10C for overnight operation (mean spirited) unless we have very young or very old family visitors, then I run overnight at 15C to 18C. I do not use Optimisation. Hope that is of use.
Last edited by killa47; 10th February 2017 at 01:44 PM.
Open vent 100 litre cylinder - I did have it set to 50 for a long time but increased it to 55 about a month ago as I couldn't quite run a full bath without temporarily turning the temperature up, and I find 60 far too hot from a tap, to the point of scalding. 55 seems a good compromise that isn't quite scalding but can fill the bath well. I have the differential set to 5 degrees.
All rooms except the bedroom are set back to 5 degrees at night. The bedroom is scheduled to 17 through the night mainly for our 10 month old son.What temperature do you have your CH overnight set-back set to?
I learnt the hard way in the first winter I had evohome that only setting the downstairs rooms back to say 12 or 14 degrees resulted in a lot of gas being burnt needlessly through the night and my costs actually went up not down!
Likewise when the house is vacant during the work day every room is scheduled to 5 degrees, and I let optimal start figure out when to turn things back on again so things are warmed up for the time that people start arriving home.
How many kWh in 25 cubic metres ?I'm using over 25 cubic metres a day at the moment! You can see why I'm interested in this stuff!
Last edited by DBMandrake; 10th February 2017 at 01:26 PM.
Further observations on our system.
I found 10C works out ok for overnights temps except when outside temps are at or close to frost levels. I used to monitor whether any zones were triggering the boiler overnight when set at 10C (our house rooms are 10ft tall. outside double skin brick walls uninsulated) but have only seen this happen once or twice - so I temporarily dropped the setpoint.
A word of warning leaving some rooms at 5C or even 10C - We came home one day and spotted condensation water on the dining room internal windows behind the curtains, causing some mould on the lining. I have since increased the temp in that room (rarely used) up to 16C to maintain a lukewarm temp to minimise condensation.
Last edited by killa47; 10th February 2017 at 02:05 PM.
I have all our rads set to 10c overnight. I have opt on for start and off. I have never had heating on overnight, even when my son was born. (S'pose it was the way I was brought up).
We also had a PIV installed when we moved to this house - best thing we ever did. Now we never get any condensation on the windows.
Hot Water Set to 55c
3 CH Zones controlled by Zwave Stats and Zone Valves Living area Zones set to 21c from 07:00 to 23:00 and then set back to 17c Bedroom Zones set to 19c 07:00 to 23:00 and set back to 17c Zones hardly ever come on During night I have Just got up here now its -1c outside but zones are still reading 18c and Boiler did not run during night
I got house Externally Insulated about 3 years ago and installed HRV this has made a huge difference to the comfort levels in the house no Condensation no ice box rooms etc
I am set to 10C overnight (22:30 and to 06:00) in all rooms apart from my conservatory. The room temperatures rarely ever drop below 14C during the night even on very cold nights. My conservatory is set to 5 C with set points taking it up to 6C and back to 5C every so often. Sometimes the heating does come on in the night and it is the TRV in the conservatory dong its stuff because the temperature has dropped below 5c. I have read somewhere that in the Winter the comfort level for humans averages between 20c and 24c but in the Summer it is 23c to 26c due to humidity changes. The drier the air the higher the temperature for comfort level. I can't convince my wife of that. She is always cold"
Posting Permissions
Reply With Quote