What is maxitrol selectra for?
Selectra Series 14+ electronic gas flame modulation systems are designed primarily for make-up air heating, as components for direct fired equipment. The system is specified for new equipment installation and may be installed on existing equipment in the field.
What is a modulation gas valve?
A modulating gas valve is used to control the temperature fluctuation by regulating the gas flow. It is commonly found in residential furnaces. The PCB board in the modulating gas valve monitors the gas input and the temperature control device (thermostat).
What is modulating float valve?
Modulating or float valves are used in surge tanks or vacuum D.E. filter tanks when the top of the tank is at an elevation above the maximum pool water level. In this type system, the water level in the surge/filter tank will rise to the same level as the pool water level when the system is shut down.
How do float valves work?
The valve consists of a cylinder that slides horizontally. In the closed position, the chamber of the float lever presses it against the water inlet to block the water. When the float drops, the piston leaves the gate and allows the water to flow.
What does a modulating control valve control?
A modulating control valve is an automated valve that is used to control the amount of flow in a system or process. They go beyond simple shutoff or isolation (on/off) and actually allow precise control of the flow rate.
What is a modulating control system?
Modulating controls are devices that are used to regulate control loops in a process. One plant may have multiple control loops, which all require control valves to monitor and control the process variable of the particular loop.
How is valve float detected?
How is it identified?
- Mild valve float can be felt as power falling off quickly at high rpm.
- Severe valve float will be heard as a sputtering sound at peak rpm.
Where should float valves be installed?
(Fig. 1.55(b)) A float valve is mounted on the tank or reservoir inlet, below or above the requested water level.
How does a modulating float valve work?
Modulating float valves are designed to regulate the flow of water in a pool recirculation system. When surges from the gutter drain spikes levels in the surge tank (or surge pit), the modulating float valve (MFV) closes, limiting the return of water coming from the main drain.
How do you float valves?
Can valve float damage engine?
Valve float means the valve doesn’t fully close at the proper time, because the return mechanism (usually a coil spring) isn’t strong enough to close it. This usually happens at high RPM. It can damage an interference engine if the valves make contact with the top of the piston.