CSE User's Manual

California Simulation Engine


DHWLOOP constructs one or more objects representing a domestic hot water circulation loop. The actual pipe runs in the DHWLOOP are specified by any number of DHWLOOPSEGs (see below). Circulation pumps are specified by DHWLOOPPUMPs (also below).


Optional name of loop; give after the word “DHWLOOP” if desired.

UnitsLegal RangeDefaultRequiredVariability
63 charactersnoneNoconstant


Number of identical loops of this type. Any value \(>1\) is equivalent to repeated entry of the same DHWLOOP (and all child objects).

UnitsLegal RangeDefaultRequiredVariability
x \(>\) 01Noconstant


Loop flow rate (when operating).

UnitsLegal RangeDefaultRequiredVariability
gpmx \(\ge\) 06Nohourly


Inlet temperature of first DHWLOOPSEG.

UnitsLegal RangeDefaultRequiredVariability
oFx \(>\) 0DHWSYS wsTUseNohourly


Fraction of hour that loop circulation operates.

UnitsLegal RangeDefaultRequiredVariability
x \(\ge\) 01Nohourly


DHWLOOPSEG pipe heat loss adjustment factor. DHWLOOPSEG UA is derived (from wgSize, wgLength, wgInsulK, wgInsulThk, and wgExH) and multiplied by wlFUA. Note: does not apply to child DHWLOOPBRANCHs (see wbFUA).

UnitsLegal RangeDefaultRequiredVariability
x \(>\) 01Noconstant


Specifies electrical power available to make up losses from DHWLOOPSEGs (loss from DHWLOOPBRANCHs is not included). Separate loss makeup is typically used in multi-unit HPWH systems to avoid inefficiencies associated with high condenser temperatures. Loss-makeup energy is calculated hourly and is the smaller of loop losses and wlLossMakeupPwr. The resulting electricity use (including the effect of wlLossMakeupEff) is accumulated to the METER specified by wlElecMtr (end use dhwMFL). No other effect, such as heat gain to surroundings, is modeled.

UnitsLegal RangeDefaultRequiredVariability
Wx \(\ge\) 00Nohourly


Specifies the efficiency of loss makeup heating if any. No effect when wlLossMakeupPwr is 0.

UnitsLegal RangeDefaultRequiredVariability
x \(>\) 01Nohourly


Name of METER object, if any, to which DHWLOOP electrical energy use is recorded (under end use dhwMFL).

UnitsLegal RangeDefaultRequiredVariability
name of a METERParent DHWSYS wsElecMtrNoconstant


Optionally indicates the end of the DHWLOOP definition.

UnitsLegal RangeDefaultRequiredVariability

Related Probes: