I have designed two hydronic (water-heated) seed dryers for Wild Garden Seed. Contact me if you are interested in either of the designs below or a custom design for your seed/other drying needs.
Advantages of hydronic heating:
- Even heat throughout
- Avoid scorching/overheating – no point is warmer than the water temperature of 110º-130ºF
- Reduced fire hazard vs. combustion-fired or electric-heated dryers
- Possible integration with existing hydronic greenhouse bench heating or indoor hydronic heat.
Greenhouse dryer
- Four shelves, 3′ x 16′ with Delta-T(TM) heat transfer tubing and manifolds. Three of the four shelves are removable; the system converts from 192 sq. ft of drying area in summer/fall to 192 sq. ft of heated bench area in winter/spring.
- Off-the-shelf 4500-watt electric water heater as heat source, 130ºF water temperature.
- 16 drying screens, 3′ x 4′, four magnetic doors for easy loading/unloading.
- With doors removed, functions as 4500-watt space heater on cold days.
Indoor model
- Shape/size customized to fit in available space.
- Over 300′ of PEX tubing provides very efficient heat transfer: 110ºF water temperature will maintain 85ºF air temperature.
- Enclosed fan and ducts on three sides create steady, one-directional airflow across drying screens.
- Twelve drying screens, 26″ x 30″, total 65 sq. ft. drying area.
- Heat source is 2000-watt, 120V electric water heater.
- Doubles as 2000-watt space heater when vents fully open.
