Hometronic HCM200d Boiler Cycling

[drawdog]

I am experiencing the Hometronic boiler cycling problem, does anybody please have a solution?

The equipment consists of HCM200D, HC60NG and HR80’s so it’s not very complex, despite numerous and lengthy experiments the system continues to cycle the boiler at exactly ten minute intervals, for 5-6 minutes each time. It’s so regular that the problem must be a software glitch. The HR80’s haven’t lost contact with the HC60NG, no faults are indicated anywhere, etc. Details :

HCM200d P4 V6.0 UK
22 Nov 2004 12:00
433 V 13 868 V A1
Device ID 01-022015

I know this issue has been mentioned before but I can't believe a solution hasn't been found, or else offered by Honeywell

[toscal]

I guess you have seen this thread http://www.wordpress-1219309-4387497...ead.php?p=8375 As what you described seems to be this boiler cycling it mentions 2 mins on 8 mins off would give you the 10 mins cycling you describe.
Have you looked at your set point temps.

Have you tried contacting Honeywell or looking on the Honeywell website for more info. http://europe.hbc.honeywell.com/prod...a/md_le21.html
or

http://europe.hbc.honeywell.com/products/ssearch/index.php?w=HCM200D

[drawdog]

Thanks Toscal, it feel's like I've trawled the entire internet for an answer but without success and was hoping somebody else may have stumbled across a solution !

I've tried combinations of set-points, offset's, etc without success. This problem has 'firmware upgrade' written all over it. I'll try the Honeywell chaps (as others have done) and report back (if they do !)

[ukhauk]

Hometronic HCM200d Boiler Cycling

Hi is the red light flashing on the HC60NG if so what frequency

can you hear the HC60NG energising just thinking it might be a fault on the boiler wiring

[drawdog]

No red lights, no faults, no comms errors. I've spoken with 'sensible heat' who were very helpful, they say that if any HR80's are hovering close to the room set-point the HC60NG will start to cycle at 10min intervals (default settings, can't be changed). The cure is to lower the setpoint in that room, or otherwise interupt the boiler feed with a timer. I'll try tonight and report back....

[drawdog]

Problem Solved

Ok, I've tried the options and can report back...

The system is working as intended, no faults (apart from the user)

As any of the HR80 valve heads reachs it's set-point it will send a request to the HC60NG to provide heat. As the rate of temperature fall is very small the request is for a minimal response, thus the inbuilt firmware provides a 10min cycle which enough to maintain the room at that set-point. Should the rate of temperature fall increase (ie the room needs more heat to remain at set-point) the GC60NG requests continuous heat and overrides the cycling.

This can occur at any single valve head, or multiple, and you can't easily tell which unless you compare room vs set-point conditions, etc and then alter the set-point to see the result.

To overcome the 10min cycling you simply have to avoid the above situation. This can be done by reducing set-points to a degree where the problem stops, or otherwise artificially produce an increased heat demand and matched cool-off period with timer entries to lengthen the cycles

Hope this helps. If you lower overnight set-points then using the optimisation function will help stop heat-up complaints.

[Crabby]

That's a very useful analysis and explanation of the cycling feature of the Hometronic system. Thanks.

[drawdog]

Not a problem, the system is outstanding in terms of simplicity in use and ability. The only downside is the cost I guess..?

I'm a fan however, the option to add various modules in the future is very attractive