Okofen pellematic regulator adjustment CMP1.4 2007

[dirk pitt]

yes the connection to UW can refine even more and also prevents the V3V does not move.
let us know about the change in behavior of the boiler.

[Jean-Jacques]

a diagram is faster .. but unfortunately I fall back into short cycles of 18mm (I arrived at 23 ..) snif
start 71 as expected

[Jean-Jacques]

I go back down my 5-8 to 12 .. and the boiler will only restart at 63 ° with a cycle of 23! how are you doing this?

[dirk pitt]

explains a little better what is the behavior with the new parameters.
is restart after shutdown good at 71?
until the temp goes down during the start, the regul, etc.
In short, redo us a little excel chart to understand what is happening.

[Jean-Jacques]

well it's the same as the previous one but you move the "start" point to 63 ° "instead of 71. the cycle lasts 22 to 23 minutes on average. ditto for the stopping time. do 5 like this.
I have nothing to change other than the 5-8 has 12 and down the P281 63 pump because I always 40-45 ° in hot water outlet for nothing, so I prefer to send it in the radiators. pump stops when the burner resets at 63 and raises to 64 ° - the v3v never closes as opposed to the scheme.

[dirk pitt]

so wait, for me to understand: with a restart at 71 ° (P202-5 °) and a setpoint 69 ° (P263) so below, the modulation should very very quickly lower its power and thus stabilize the boiler temperature.
so 2 possibilities:
either the modulation drops rapidly as expected and if the temperature continues to rise, it is that the heat demand is too low.
either the modulation is not fast enough and the power is too important. we must find why.
can you take a reading with the parameters that I used and the modulation values.
on the other hand, what do you mean by: "I always have 40-45 in hot water outlet for nothing" where do you have 45 °?

[Jean-Jacques]

Hello,
45 on the boiler output sensor for hot water radiator.
it is always at 63 ° 5 barrettes -cycle 23mm and gradually goes up to 76 ° 1 barette. the modulation has air proportional to the rise in temperature.

[dirk pitt]

Hello,
45 on the boiler output sensor for hot water radiator.
it is always at 63 ° 5 barrettes -cycle 23mm and gradually goes up to 76 ° 1 barette. the modulation has air proportional to the rise in temperature.

OK, so it looks like the modulation is working properly.
on the other hand it is necessary to specify the point on the temperature of which you speak (I know, I am a little fastidious, but often the devil is in the details.
at the outlet of the boiler, the water can not be at 45 ° since it is between 63 and 76 °.
it may be at 45 AFTER the V3V because some of the boiler water is mixed with return water from the radiators.
it must be understood that the V3V obeys only the law of the regulation to send the radiator water at the desired temperature depending on the external temperature and the ambient eventually. the V3V does its job independently of what happens in the boiler.

to return to the symptoms of your case, it seems that the cycle is simply short because the demand is low. the demand is the amount of hot water demanded by the V3V. if it is warm enough in your house (room temperature equilibrium), the V3V is not open and the heat produced by the boiler even modulating is too important, so its internal temperature rises and it ends up stopping. nothing abnormal about that. current outside temperatures are not too low, if you are well insulated, that may be the reason.
on the other hand if it is cold, you have difficulty to climb in indoor and cycles do not extend, the problem is not on the boiler but on the radiator circuit: either too low a curve setting is a circulator too weak, or an unbalanced circuit, etc.

[Jean-Jacques]

then yes the probe is after the v3v - so water mixed with the return.
I am on a slope 1.6 - it is 11 ° outside and it corresponds to 47 ° hot water on the graph with a foot at 40 °.
I ask 19 in ambient tp that I have widely.

2 things I understand for start up
-It is boiler automation priority P202-5 so 76-5 = 71 ° if the regulator P5-8 adds to P4-7 is greater than 202 63 + 18 = 81
start at 71
cycle = 18 '
-or regulatory priority if P5-8 + P4-7 less than or equal to P202 63 + 13 = 76
start at 63
cycle = 21 '

is not it better that the cycle starts from 63 so that it is longer + modulated?

ps - v3v changes between 60 and 80% open all the time

[dirk pitt]

in your case, now that your circulator is on UW, it may be better to let restart on regulation set rather than on the PLC but cons I will put a rebar instead to 66 ° and not 63 because at the time of restarting , it keeps going down and you have to avoid that it goes down too much under 65. since your P281 = 64, it is necessary to restart the boiler above this value.
it seems that you are slightly over-sized.
we should see what happens when the temperatures are a little colder.
also try to get down from 1 ° the setpoint P263