Which drinker are you heating?
Choose the model you are specifying. Insulated and closed-top bodies lose far less heat, so the same capacity needs much less power. Use the buttons to narrow the list by volume.
Where will it stand this winter?
Heat loss is driven by the gap between the water you want and the air around it. Start from a climate preset, then fine-tune it for your site.
Advanced · calculation assumptions
Choose the heater input voltage
This is the heater's input voltage, not your site supply: 24 V / 36 V come from the control box transformer, 220 V runs directly on the mains.
Your heating specification
Required power already includes a 15 % safety margin over the calculated heat loss, so the system still holds temperature on the coldest night.
Where the heat goes
? –Steady-state estimate of the heat loss. The required heater power above adds a 15 % safety margin on top. Full assumptions are listed at the bottom of this page.
Not sure which drinker your herd needs? Start with the drinker matching tool, then come back here to size the heating.
How the calculation works
- Body: double-wall 5 mm PE construction. Insulated models carry 50 mm of polyurethane foam (≈0.024 W/m·K) in the cavity; uninsulated models have an air gap (equivalent conductivity 0.10 W/m·K by default, adjustable above). Closed-top models add a double-wall lid.
- Wall area: for open troughs the wetted area is derived from the open surface plus the capacity; for closed bodies it is estimated as A ≈ 6·V2/3.
- Surface loss: open water loses heat by evaporation (latent heat ≈2.45 MJ/kg, driven by the humidity ratio difference), convection and radiation. Closed bodies have no evaporation term.
- Selection rule: the smallest fixed module available at the chosen voltage that covers the required power. If none does, the alternatives at other voltages are listed.
- Warm-up time: heating the full volume from the starting water temperature to the target, with the steady-state loss deducted along the way.
- Outside film coefficient: 5.7 + 3.8·v for the wind speed you enter, with a 4.5 W/m²K radiation allowance.
Good to know before you order
- Every trough continues to work without power down to about −15 °C, because the closed body, cover and float hold the water in. Heating raises that limit and keeps the water at 15–25 °C.
- This voltage is the heater's input voltage, not your site supply. A drinker is supplied as a control box + heater set: the 24 V and 36 V control boxes contain a transformer and are wired to the local mains, outputting the voltage you choose. The 220 V version has no transformer and runs directly on the mains.
- Choose 24 V where local regulations require the voltage of products animals can touch to be no higher than 24 V; 36 V is the preferred safe voltage; 220 V costs less because it carries no transformer.
- Several troughs take more than one heater — check the selection guide on the Heated Drinker page for how many units a long trough accepts.
- Heating elements are field-replaceable in about two minutes, with dry-burn and overheat protection built in.
- Site conditions differ from any model. For a firm guarantee on the coldest night, send us your climate data and we will confirm the configuration.
Disclaimer
Engineering estimate. Results come from a steady-state heat-loss model and are intended for sizing, not as a performance guarantee. Extreme or unusual conditions deserve extra safety margin — confirm the final configuration with our technical team and against the actual supplied configuration. Product photos are illustrative; refer to the delivered specification.