Our latest round of updates is focused on the zone and equipment selection options. You can now select variable speed circulators, model variable capacity equipment more realistically and select to use no supplemental heating.
Variable Speed Circulators
Assigning a variable speed circulator allows the system to ramp up and down the amount of flow that is being pushed across the coil and through the ground loop to maintain the target delta-T. For some dual capacity units there is an additional control option that allows you to specify discreet flow rates for high and low capacity operation. By default, RLC assumes the more common control over delta-T.
Variable Capacity Heat Pumps
We additionally implemented full support of variable capacity heat pumps. The equipment has been in the system for some time however, we treated it as dual capacity equipment. Projects in the system that used the original method of variable capacity equipment treated as dual capacity remain untouched. The heat pumps have just been flagged as outdated.
If you would like to go back into your old projects and update them to use a truly variable capacity model, simply open the zones and re-select your equipment.
There are cases where designers have no intent of using a strip heater or other form of supplemental heat for the system. If the heat pump is sized to 90% or greater in heating, there arguably shouldn’t be very many bin hours where the GSHP system is unable to maintain set point temperature. RLC now gives you the ability to turn off the supplemental so long as you have sufficient heating capacity assigned to the zone.
As a word of caution, just remember that systems without supplemental may have extended run times where the heat pump is simply unable to satisfy the call for heat. This isn’t necessarily a bad thing, but homeowners tend to like their thermostats satisfied.