Make sure the new sensor is in good thermal contact, and well insulated from the
air. This is critical with sensors on either collectors or outside piping, but it is also
important with sensors inside the building.
Connections on sensor wiring should be made with either the proper size wire nut,
or a crimp-type solderless connector.
If wire nuts are used, screw the connector on the stripped wires, then fill the nuts
with silicone sealant. Finally, tie a knot in the wires for strain relief.
If crimp-type connectors are preferred, either use one filled with silicone (such as
the UITM connector by 3M), or cover the joint between the wire and the connector
after crimping it. Soldering sensor wire connections is not necessary and is not
recommended. Use enough cable ties or insulated staples to support and protect
the wiring. Do not use regular staples, particularly from a stapling gun. These will
short out the wiring.
Check the operation of all sensors before leaving the site. Information in Section
4.3.1 describes this procedure.
In some systems, one or more freeze snap switches are installed in series or
parallel with the collector sensor. In others, they are part of a separate circuit.
Be sure the freeze snap switches used with a control are made or
recommended by the control manufacturer. Some switches open on a
temperature drop, and others close on a temperature drop. The use of
the wrong snap switch can allow the collectors to freeze.
Remember, many control problems are caused by defective or poorly installed
sensors or sensor wiring. Make sure the control is really defective before replacing
5.2 REPAIR PROCEDURES