2
Disconnect power supply to fans and/or accessory controls when reversing fan direction or servicing the X
CHANGE
R
TM
. Failure to do
so may result in personal injury and/or equipment damage.
Make certain the power source is adequate for the X
CHANGE
R
TM
requirements. Do not add the X
CHANGE
R
TM
to a circuit where the
total electrical load is unknown.
TJERNLUND OPTIONAL DH2P DEHUMIDISTAT CONTROL MODULE OPERATION
The DH2P control module includes an adjustable dehumidistat control which activates the fan(s) if the relative
humidity rises above the selected set-point. It is generally recommended to maintain a Relative Humidity (RH)
below 60% to inhibit mold growth. The dehumidistat can be turned fully clockwise to the ‘on’ position for con-
stant fan(s) operation or it can be turned fully counter-clockwise to ‘off’ during seasons or times when it is not
desired for the X
CHANGE
R
TM
fan(s) to run. Each fan can be independently turned on/off by its fan switch on control
module.
STANDARD PLUG-IN TIMER OPERATION
A standard adjustable timer can also be utilized for timed operation of the X
CHANGE
R
TM
fan(s). Plug timer into standard outlet and
plug X
CHANGE
R
TM
fans into wall timer.
TJERNLUND OPTIONAL SCP SPEED CONTROL OPERATION
Tjernlund’s optional SCP speed control can be used to vary the speed of the X
CHANGE
R
TM
fans. Plug SCP speed control into stan-
dard outlet and plug X
CHANGE
R
TM
fans into SCP speed control.
RECOMMENDED PATTERNS OF OPERATION
If using the optional DH2P dehumidistat control, the X2R fans can be cycled automatically based on the relative humidity level of the
house or it can be operated based on recommendations below. It is generally recommended to maintain a Relative Humidity (RH)
below 60% to inhibit mold growth.
A standard plug-in wall timer can be programmed based on the lifestyle or needs of the occupants. For example, a family with smok-
ers may want to cycle the X
CHANGE
R
TM
more frequently than a family of non-smokers.
Another timed method may be to cycle the X
CHANGE
R
TM
during peak usage of exhaust fans, such as bathroom, kitchen, laundry or
utility. Outdoor air should be brought in at these peak times to help balance out pressure inside the house.
The X
CHANGE
R
TM
can be cycled on and off at regular intervals to periodically provide fresh air to the home, exhaust stale air or have
one fan bring air in and the other fan exhaust air for a balanced air exchange. It can also be ran like an economizer to bring outside
air in during evening time when it is cooler outside.
HYPOTHETICAL XCHANGER OPERATION BASED ON LIFESTYLE
The example below shows a possible way in which cycling times of the X
CHANGE
R
TM
may be determined based on household
occupant lifestyles.
6:00 A.M. to 9:00 A.M.
= Outside fresh air should be brought into the house to compensate for morning routines. Bathing, cooking,
laundry and other activities such as smoking necessitate that outside fresh air to be brought in. Depressurization of the house at these
times is common with many exhaust fans running at one time.
9:00 A.M. to 4:00 P.M.
= House is normally vacant with occupants at work or school. Cycle X
CHANGE
R
TM
on and off for 15 minute
intervals per hour to assure fresh air is supplied to the house.
4:00 P.M. to 8:00 P.M.
= Outside fresh air should be brought into the house to compensate for evening routines. Bathing, cooking,
laundry and other activities such as smoking necessitate that outside fresh air to be brought in. Depressurization of the house at these
times is common with many exhaust fans running at one time.
8:00 P.M. to 6:00 A.M.
= All members of the household are usually present. Outside fresh air is needed to dilute occupant generated
carbon dioxide during sleeping. Cycle X
CHANGE
R
TM
on and off for 15 minute intervals, with occasional 30 minute intervals to assure
fresh air is supplied to house.
