Visionpro 8000 series

ChrisJ

I may have asked this previously but I cannot find a thread on it.  With the Visionpro 8000 series is there anyway to increase the temperature swing? 



I have mine set to 1CPH which is fine, but in the fall and early spring I would rather it swing 2 or 3 degrees to save on fuel. 

Hap_Hazzard

Would it save $$?

When the subject of setbacks comes up, the consensus among the pros has been that they don't save money because of the cost of restarting and reheating a cold system and then having to heat a cold house. But some of them seem to feel that 2-3 degrees is not excessive. If that's the case, maybe setbacks are the way to go when the outdoor temps are moderately cool?

ChrisJ

Not a setback

I'm looking to do this in mild weather when the entire system is cold to begin with. My issue is it doesn't make sense to run the system to gain 1 degree when it takes 15 minutes to get steam up to the radiators and then only produce heat for 3 minutes running a total of 18 minutes. It would make more sense to wait for it to drop 2 or 3 degrees and then bring it back up, maybe running for a total of 20 minutes.



When its actually cold out it makes more sense to maintain a more constant temperature as the piping and boiler won't cool down as much.

JStar

VisionPro

Try changing setting 680 to 1 instead of 2. That should let the temperature drop lower than normal.



Otherwise, I don't think there is a way to do it.

Rod

DOM Relays

Hi Chris-

   Maybe this is something that might be of interest to you. A couple of years ago there was discussion on using “Delay On Make” (DOM) relay on the thermostat circuit.  I made some notes on the relays discussed:

ICM 102 (max setting - 10 min)

http://www.icmcontrols.com/TIME-DELAY-RELAYS-DELAY-ON-MAKE-DOM-Prodlist.html

Allied Electronics  - relays  - Many types - up to 300 hr delay 

http://www.alliedelec.com/search/searchresults.aspx?dsNav=N:106-4294856062



As I remember it the discussion centered around short cycling though it would seem to me that DOM relays would also accomplish the result you seek.

- Rod

Mark N

VisioPro

I think your misunderstanding how your thermostat works. The CPH setting replaced the anticipator. By setting the CPH to 1 your already getting the longest off times. Your thermostat will maintain the temp within 1 degree of the set point. The CPH has to do with what type of system you have. If you want to save money in the milder weather use a lower set point.