AC Infinity - SUNCORE H3 Seedling Heat Mat 25.4 × 52.7 cm

A 25.4 × 52.7 cm heat mat with a digital controller that measures the temperature and holds it. The mat matches a standard seed tray, is sealed to IP67 and rolls up into the nylon bag supplied with it.

Two numbers on the display, and that is the whole difference

The controller shows what the sensor reads next to the value you set. While your value sits above the reading, the mat heats. Once the reading meets your setting, the mat stops heating until the reading drops again.

That sounds unremarkable, and it is exactly what a mat without a sensor cannot do. A mat that only knows a level puts out that level whether it is eight in the morning or three in the afternoon. If your room warms up during the day, the root zone simply climbs with it. With feedback it does not: the mat drops out as soon as the target is met and comes back when the night cools things down.

So a mat that switches off now and then is not a mat losing its grip. That is the controller doing its job, and it is why a seed tray under this mat has a flatter day than the room around it.

Setting it and hanging it

The arrow buttons move your target up and down. Hold them together to swap between Celsius and Fahrenheit, because the controller starts in the American unit. Ten seconds on the power button returns everything to the factory setting.

The controller hangs from a single screw, and an anchor and screw are supplied for it, so the display sits at eye level on a wall or a tent pole instead of leaving the cable across your bench.

The mat itself

Heat comes from infrared film rather than from wire, so the whole surface takes part and there are no warm lines running under your seeds. The mat works in a band of 26.7 to 30.6 °C and lifts the root zone by up to roughly 11 °C above the temperature of the room. The outside is multi-layer PVC that rolls up and wipes clean.

Technical Specifications:

• Model: AC-SMH3
• Dimensions: 25.4 × 52.7 cm
• Control: digital controller with sensor, measures and holds
• Display: measured value alongside your setting
• Units: Celsius or Fahrenheit, switchable
• Power draw (max.): 20 W
• Band of the mat: 26.7 to 30.6 °C
• Above ambient: up to roughly 11 °C
• Heating element: infrared film
• Outer layer: multi-layer PVC, rollable
• Ingress protection: IP67, seams and cable entry sealed
• In the box: nylon storage bag, anchor and screw for the controller

Frequently asked questions

How does this differ from the SUNCORE S3?
It is the same mat: same size, same 20 W, same film, same IP67. The whole difference is the controller. The S3 has a three-position dial and measures nothing, this one measures and regulates. What you pay for here is feedback, not surface.

My mat goes cold now and then, is it faulty?
Probably not. When the reading reaches your setting, the heating switches off until things cool down. If you watch the reading hover around your setting, it is working as intended.

Can I use it for anything else?
AC Infinity name terrariums, home brewing and fermenting themselves. Anything that needs gentle, steady warmth within the band of the mat will do, as long as you stay indoors and never submerge it.

Can I put a thick-bottomed tray on it?
You can, but any insulating layer holds back the heat you want in the medium. Lay the mat flat without folds, and put nothing warm underneath it.