Exam 33: Hydronic Heat

In a series loop, the water going through the last terminal unit will be the same temperature as the water through the first terminal unit.

Why must the expansion tank always be located higher than the boiler?

What is the purpose of a system pressure differential bypass valve?

The vanes of the impellers used in circulating pumps in hot water heating systems are usually enclosed, and are referred to as ____________________ impellers .

The only place a bleed valve is needed is on top of the boiler.

Explain the purpose of the pressure relief valve.

Automatic air vents rely on an internal disc that swells when water is sensed.

Discuss the outdoor reset control.

On systems that use two-port zone valves, excessive pressure in the supply header may result when multiple zone valves ____________________.

Hydronic heat circulators are centrifugal pumps.

A high-limit control on a hot water boiler is needed to ____.

What would happen if a hydronic system was installed without an expansion tank?

The expansion tank provides a means of removing the air from the system as well as provides ____ .

An expansion joint is a device used to ____.

Zone control valves are controlled by ____________________.