Boiler Thermostats
Capillary boiler thermostats for solid-fuel and liquid-fuel boilers, hot water cylinders, and circulation pumps: single and dual (with safety thermostat) models.
Products (8)
- IMIT 542441 TC2 Boiler Thermostat, 40-210°C – $19.94
- IMIT 542714 TLSC Boiler Thermostat, Dual, 0–90°C – $69.28
- IMIT 544610 TA Boiler Thermostat, 0-40 °C, Incubation Thermostat – Request a quote (out of stock)
- IMIT 545610 BRC Boiler Thermostat, 20-90°C, Surface-Mount – Request a quote (out of stock)
- Welko Boiler Thermostat, 0–90 °C, Dual Contact – $15.48
- Welko Chain Boiler Thermostat, Mechanical, 0-90 °C – $24.99
- Welko Dual Boiler Thermostat, 0–90°C – $32.85
- Welko Incubator Thermostat, 0-40°C – $21.02
What does a boiler thermostat do?
A boiler thermostat is a control device that senses the temperature of the water in the boiler and commands the burner, fan, or circulation pump. It is widely used in solid-fuel boilers to start the circulation pump when the boiler water reaches a set temperature and to stop it when the water cools down. This prevents cold water from being circulated unnecessarily and helps protect the boiler against condensation and corrosion.
Thermostat types
- Single boiler thermostats: Provide operating control based on a single setpoint.
- Dual boiler thermostats: Combine an operating thermostat and a safety thermostat in one housing; shut down the system in the event of excessive temperature.
- Incubator thermostats: For applications requiring precise control in a low temperature range.
- High-temperature thermostats: Wide-range models for ovens and industrial heaters.
Use in pump control
In solid-fuel boilers, the pump thermostat is typically installed in the immersion pocket at the boiler outlet. When the boiler water exceeds the set temperature, the contact closes and the circulation pump runs. The setpoint should be determined according to the boiler manufacturer's recommendations and the configuration of the system. The safety thermostat provides an additional layer of protection by cutting the burner or fan if the boiler water reaches dangerous temperatures.
Installation and wiring
The sensor must be pushed all the way to the bottom of the immersion pocket, and contact can be improved with heat-conducting paste if necessary. Wiring connections must follow the device's wiring diagram; if loads such as pumps and fans exceed the contact rating, a contactor must be used. The capillary tube must not be sharply bent or allowed to touch hot surfaces. Electrical work must only be carried out with the power switched off.
Frequently asked questions
What temperature should the pump thermostat be set to?
The setting should follow the boiler manufacturer's recommendation; too low a setting will cause the pump to circulate cold water.
Why does the safety thermostat trip?
The boiler water may have overheated, the pump may not be running, or circulation in the system may be blocked; do not reset it until the cause has been resolved.
Is a dual thermostat mandatory?
It depends on the boiler type and the manufacturer's recommendation; the safety thermostat provides an additional layer of protection.
Are thermostats used in combi boilers?
Combi boilers have their own control system; room thermostats are used for ambient control.
Where is the sensor installed?
It is installed in the immersion pocket on the boiler outlet line or in the boiler body.
What happens if the thermostat fails?
The pump or burner may run at the wrong times; if a measurement is suspect, replace the thermostat.