Greenhouse Dehumidifier — Commercial and Industrial Humidity Control Systems for Greenhouses, Nurseries, and Grow Facilities

Size by moisture load, not floor area. Plants put about 95% of their irrigation water back into the air, so in a sealed or semi-sealed house the water you remove roughly equals the water you irrigate. Start from daily irrigation in liters, multiply by 0.6–0.9 for the substrate, and add 20–30% headroom for peak transpiration. As rough planning figures: a propagation house up to 30 m² needs 30–90 L/day (GDH-50E to GDH-90E); a mid-size glasshouse of 100–300 m² needs 240–600 L/day (GDH-CE156 to CE380); a large range of 300–800 m² needs 600–1,440 L/day (GDH-CE480 to CE720, or floor-standing GDH). Send your irrigation volume, house size, and crop for an exact figure.

Most greenhouse crops sit well at 50–70% RH, but relative humidity on its own is misleading because it shifts with temperature. Growers increasingly control to vapor pressure deficit (VPD), roughly 0.4–1.6 kPa depending on crop and stage. Disease pressure climbs sharply above about 85% RH, so the practical rule is to hold RH below 70–75% during disease-susceptible stages while avoiding over-drying. Propagation is the exception — cuttings and seedlings root best in damp air around 65–80% RH.

Three differences. Sizing — a greenhouse unit is sized to transpiration load in liters per day, not to room area. Cold-weather performance — greenhouses run cold and wet, so units need automatic defrost, or a desiccant rotor, to keep removing water at low temperature, where many home units simply stop. Air distribution — greenhouse units are built to spread dry air across a planted house and hold conditions even, rather than drying one spot. A home dehumidifier dropped into a commercial house usually undersizes the load and frosts up in winter.

Often, yes. Fans move air and help stop condensation on leaves, but they do not take water out of the house. Vents remove moisture only when outside air is cooler and drier than inside; on cold, wet, or humid days, opening vents dumps heat and CO2 without fixing the humidity. A dehumidifier removes water by recirculating the air, so it holds humidity down with the vents shut and the heat and CO2 kept in. Fans and a dehumidifier work together: the fans keep air moving, the dehumidifier takes the water out.

Yes, and that is when it matters most, because condensation and disease pressure peak in cold, wet weather when venting is off the table. A compressor unit needs automatic defrost to keep working as coil temperatures fall — SHISHUO greenhouse units use M-CoRR heat-recovery defrost for steady removal down to 5°C. Below that range, the ROD desiccant series holds humidity down where compressor coils lose efficiency and frost up. For cold-climate houses, we match the technology to your winter conditions.

Yes. SHISHUO is a manufacturer, not a trading company — we build the GDH-CE, GDH, and ROD series at our Jiaxing facility and supply factory-direct. That means specification help from our engineering team, no distributor markup, and OEM/ODM options for growers, builders, and distributors.

Yes. The GDH-CE ducted range runs to CE720 and the GDH floor-standing range to GDH-1440E, covering large glasshouses, nursery complexes, vertical farms, and multi-bay ranges. Big footprints usually run several units in parallel for even humidity and maintenance redundancy, and we help plan multi-unit layouts so dry air reaches the whole house.

Yes. We support OEM (your branding on our hardware) and ODM (voltage, filtration level, controls, cabinet, and duct or drain configuration). Standard units are 220V/50Hz and 380V, with 110V/60Hz and 240V/50Hz on ODM. Units are built to CE, ETL, RoHS, and ISO 9001, and we export worldwide — send your destination market for the applicable certificates and a quotation.