Boiler Aquastat Control

The boiler aquastat control device is used to regulate the temperature of water in your boiler and operate the pump that circulates hot water in the heating system. The way in which the boiler aquastat operates is the same way in which device that controls pressure for a boiler that is powered by steam. It also works in a similar manner as the limit control device for a forced air furnace system. The boiler aquastat has a heat sensing element that is filled. This element allows the device to switch on and off automatically and is designed to notice when the water temperature in the boiler rises and falls. It is typically attached to the supply riser in the boiler or mounted, with the heat sensing element placed inside the well of the steam boiler.

The Types of Boiler Aquastats

There are different types of boiler aquastats depending on its designed function. That function can be to control the temperature or turn on the fan for the circulator in the boiler. If function of the aquastat is to control the boiler temperature, is closes whenever the internal temperature falls and correspondingly opens when the temperature inside the boiler increases. The aquastat closes when the circulator is in operation as the internal temperature increase. The different types include the direct action, reverse action and double action aquastats, which are all strap-on types.

Strap-on Type Aquastat

An aquastat that is placed on the boiler is a stap-on designed to react when the temperature of the water rises and falls as it is fed and runs along the supply riser. The switching for the aquastat is either a direct, reverse as well as the models that are double action.

Direct Action Type Aquastat

The direct action aquastat is used to operate the circuit as the temperature inside the boiler rises. The aquastat’s setting to shut off when being used for high temperature operation is kept low in order to maintain the proper setting and operation when operating the boiler in colder weather.

Reverse Action Type Aquastat

An aquafast that is the reverse action type is placed on the steam boiler above the valves near the boiler’s return lines. Its placement is on the riser, which is the largest, from the boiler and used to prevent the circulator from operating whenever the water temperature insider the boiler falls. It is the job of the reverse action aquastat to shut the circuit insider the boiler when the temperature increases.

Double Action Type Aquastat

An aquastat that is the double action type is used to start circulator operation with a single switch actuation. It also functions as an operating control, maintaining the boiler water temperature. A double action type aquastat is placed on the largest riser. It should be placed above any valve and where it is subject to the temperatures where the boiler is at its maximum.

The strap-on aquastats described above can be placed anywhere on the steam boiler. The area that the strap-on aquastat is placed should be completely clean and any corrosive elements should be cleared when mounting a strap-on aquastat.