Dear equest users,

I am currently modeling a 4-pipe fan coil system connected to a ground source heat pump.

I followed this approach to develop the water-side HVAC within equest

1. Create a 'chiller' of the type 'water-to-water heat pump'
2. Create an independent circulation loop of the type 'lake/well'
3. Create a ground loop heat exchanger of the type 'lake/well'
4. Select as the chiller CW loop and GLHX circulation loop the
independent loop you created - they should connect without errors
5. Assign a custom temperature schedule for the lake/well ground loop
in the screen that pops up when you double click the GLHX (read on)
6. Make sure the default head/pump properties for the circulation loop
and GLHX make sense for your system - adjust as necessary. (i.e. if it's a
closed ground loop, there shouldn't be static head)

as explained in this thread "loop to loop heatpump in equest"

http://lists.onebuilding.org/htdig.cgi/equest-users-onebuilding.org/2009-July/001862.html

Instead of using a custom temperature schedule for the lake/well, I am considering a constant temperature all year around (15?C)

Does that assumption has significant impact on the modeling itself ?.

Also, by using a loop-to-loop heat pump, I am no able to change the heating EIR efficiency/curve. See schematic and image attached.

Do you have any idea how to change the heating EIR because it is grey out on my model.

Let me know if I am on the right track

Thanks,

Nicolas Mercier