[Equest-users] 2-pipe fan coils w/ electric shoulder

[Ana N.]

Dear e-quest users,
 
Has anyone had success modeling 2-pipe fan coils with electric shoulder?
 
The system operates using the following schedule: 
-         Fan coils provide cooling March through December
-         Fan coils provide heating December through March
-         Supplemental electric heaters will provide heating during October, November, April and May when required.
 
I was able to model 2-pipe fan coils by connecting 4 pipe fan coil to 2 pipe circulation loop and using schedules to define changeover criteria. This model gave me a high number of unmet load hours, much higher than I expected. As I could not figure out how to model supplemental electric heat I switched back to 4-pipe fan coils and assigned availability schedules to heating and cooling. With this configuration, I tried to use electric baseboards and baseboard schedules based on outside temperature, but my unmet hours went up, offcourse this time in cooling. I tried changing capacities of baseboards and the baseboard reset schedule, all without any success. The only idea that  I could think off is to manually calculate heat load and electricity consumption for spring-fall months. This is a huge building with almost hundred of FCs, and I am still hoping there is some better solution.
 
Any thoughts?
 
All ideas are greatly appreciated.
 
 Ana 		 	   		  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20101214/382b356c/attachment.htm>