Heating
If you have a heated greenhouse, it will be supplied with a mains powered control unit
(it has three sockets on the left hand side). The top two connectors are for heaters;
zone 1 at the top and zone 2 below it. Into these connectors you can plug Harvst heater
pads. The bottom connector is for Harvst waterproof LED grow lights, which are
available as optional extras.
You can use up to three heater pads for each connector.
Since the zone temperature sensors are in the same dual-purpose sensor as the
moisture detector, we recommend the following setup:
Zone 2 (top of greenhouse, with misters)
Have at least one seed tray or gravel tray filled with soil; you can germinate seeds in it.
You don’t need sensors in every seed tray, so you’ll use this one to control the
environment on the top shelf. This will be your “control” tray. Put a heater pad into the
bottom of an empty seed tray, and then place your control tray into that. Slide the dual
purpose sensor down the side of the soil in the top tray, so it measures the moisture
and temperature of the control tray. When the control tray gets dry (or too hot), we can
assume that other seed trays on the same level are about the same.
Zone 1 (bottom of greenhouse, with sprayers)
Larger tubs in the bottom will heat up much more slowly than seed trays, so they need
to have different heating control. Just as you have a control tray in the top, you can
have a control tub in the bottom, which contains the dual-purpose sensor. If you have a
Yard model and are planting directly into the ground then we suggest your zone 2
control tub is on the middle shelf. Put the heater pad into the bottom of your growing
container before filling it with soil. If you’re confident you are going to keep this
container for this use, then peel off the back of the heater pad and stick it securely to
the container. You won’t be able to get it off again easily. Place the sensor flat, just
under the surface of the soil. We’ve found this is a good position to get good moisture
and temperature readings.
