Lifebreath 60DHW(T), 60VENTAC, 60DHWDF(T), 60DHWH(T), 40VENTAC, 4TONVENTAC Optional Dehumidistat

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Optional Dehumidistat

	Dehumidistat to
	Dehumidistat to
	Setting			Relative
				Relative
				Conditions
	Outside			Conditions
	Outside
			WINTER:
			WINTER:
	Set		dehumidistat
	Set			30% to			40%.
	between			30% to			40%.
	between				too dry,
	If	home is					.
	If		to higher			setting
	adjust			is too humid,
	If home					setting.
	adjust		to lower
			SUMMER:


	Set dehumidistat
					.
			to OFF

An optional dehumidistat can be connected to the furnace to help eliminate excessive moisture during the heating season. When the dehumidistat senses moisture in excess of the control setpoint, the blower will be overridden into high speed. This will increase the ventilation airflow and create a dehumidification affect. Typical settings are between 30-40 during the winter and OFF for all other seasons.

The dehumidistat will connect to R&G terminals on the furnace.

Part # 99-130W

Note: Do not use dehumidistat for hot southern climates.

When using a Dehumidistat or Interface Relay to initiate high speed blower operation on a furnace, certain thermostats will initiate the outdoor cooling condenser when R and G are closed.

Use this wiring configuration to stop the Dehumidistat from initializing the condenser unit. This problem can occur at the thermostat because the Y terminal is connected to the G terminal internal to the stat. When R and G are closed at the furnace (by dehumidistat or relay) 24 Volts is sent to G at thermostat. 24 Volts is then sent through Y which will initiate outdoor condenser. The relay will isolate this problem.

NOTE: This problem does not occur with all thermostats, therefore it is important to fully commission the installation to determine if this relay configuration is required.

Interface Relay or Dehumidistat

24 Volt

Relay

R G W Y C

NO

COM

NC

R G W Y

T-stat

Furnace	TB-102
	1099

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Contents OPERATION, Sizing and Installation Manual Table of Contents Introduction Description and Purpose Combo System Basic Principles Closed/Open Combo SystemAir System Call for Space Heating Only OperationCall for Domestic Hot Water and Space Heating Operation Water PipingManual Valves Throttling Valve Shut Off ValvesDrain Valve Check ValvesAnti-Scald Valve Expansion TanksCold Off Season Circulation ControlsWater Heater Thermostat Air Handler Return Air TemperatureAir Handler Temperature Rise Room ThermostatHead Pressure Design vs. Field ConditionsWater System Pressures Flow RateModel 40DHW Up Flow Dimensions & ClearancesWarranty Filters CaseModel 60DHW Up Flow 60DHWModel 40DHWDF Down Flow 40DHWDFModel 60DHWDF Down Flow 60DHWDFModel 40DHWH Horizontal 40DHWHModel 60DHWH Horizontal 60DHWHHigh CFM Lower Btuh Output 4TONDHWModel 40VENTAC Core Filters Case40VENTAC Model 60VENTAC 60VENTACModel 4TONVENTAC 4TONVENTACLocating The Unit Duct ConnectionsOption 1 Ventilation Ports Off Left Side Option 2 Ventilation Ports Off Right Side Horizontal VersionDucting Outside Ducting the Weatherhoods Locating Intake WeatherhoodLocating the Exhaust Weatherhoods Locating WeatherhoodBalancing Procedure Pitot Tube Air Flow BalancingPrior to balancing, ensure that Placement of the Pitot Tube Pitot Tube and GaugeBalancing Collar Instructions HRV Drain Line Diagram Drain Line Piping Plumbing Water HeaterClean Air Furnace Wiring Diagram ElectricalOptional Dehumidistat Start-Up Procedure Following conditions must be met prior to start-upHeating/Cooling Optional Circulation Timer ModelsOperation VentilationPump is noisy TroubleshootingLack of heat HRV core freezes upCondensation/ice forming inside ventilation ducts During cooling cycle, hot water circulates through the coilWater sits in drain pipes Humidity levels are too lowWater Pump Performance Specifications System CommissioningWorksheet for Integrated Combo System Design Part a Design Load Specifications Method a domestic hot water usage for C.1 Part D Proving Required Water Flow Commissioning of Integrated Combo System HRV Balancing McCormick Blvd. London, Ontario N5W 4C8