What type of valve is used in heat pump

The equalizer line should be connected to the coil outlet near the sensing bulb location. Again the standard off-the-shelf valve will have no internal check valve so it won't work for a heat pump application. Select the correct adaptor to fit the existing coils connection: Aeroquip, Chatleff or mail flare. Wrap the valve with a wet rag and braze the adaptor to the TXV you selected. Always attach the sensing bulb securely to the suction line on the coil outlet and wrap with insulation.

These valves are adjustable but adjustment should rarely be needed. Are you a homeowner or own a commercial property? In fact, all their valves go through multiple ruggedness-testing procedures to ensure that their customers receive the best industrial valves.

All Rights Reserved. Designed by FSC India. Connect to our newsletter to stay updated about our various evolving products and their usability in your life. It contains most of the debris that contaminates the system. The discharge line connection is always the single port connection on one side of the slide valve.

The suction line connection is always the center port on the other side of the slide valve, where there are three connections. The two connections, one on each side of the suction connection, go either to the indoor or outdoor coil, depending on how the system is configured when the pilot valve is energized and de-energized. Other than replacing a burned out coil on the pilot valve, there is no other field service for a reversing valve.

To replace the valve, one needs to know:. The voltage of the pilot valve coil. What refrigerant is in the system? Nominal line sizes. Capacity, in tons, of the heat pump.

Capacity tables in the Alco catalog are based on a 2-psi. D P across the valve suction ports. The 2-psi D P is a standard used for capacity ratings.

Undersizing the capacity rating will result in too high a pressure drop, which will cause a loss of BTU capacity of the system. Oversizing may result in poor or no operation of the reversing valve. A larger than necessary capacity rating will result in a very low pressure drop, possibly so low that the slide will not move, may chatter, or not seat well when the pilot valve is either energized or de-energized.

It is the pressure difference across the slide that moves the slide. Chances are a reversing valve in the selected capacity will have line sizes available to match the valve being replaced. It is not crucial that line sizes match up perfectly.

Fittings may be used to increase or decrease the connections to fit the existing tubing. Reversing valves can be mounted in any conceivable position. The replacement valve will usually be mounted in the same position as the valve being replaced. Except when the compressor burns out, they almost never have to be replaced.

In switch position 1 there is no voltage on the coil of the solenoid pilot valve. In this position, highly pressurized hot gas from the pilot line of the narrower connector enters the chamber containing the sliding mechanism from the right. At the same time the pressure at the left-hand side of the slider chamber can be relieved via the permanent suction connection, discharging the gas to the low pressure side.

This displaces the slider towards the left and opens the main paths at the top, leading down to the right and from left to the center. In switch position 2 the hot gas makes its way from the top towards the left, while suction gas is simultaneously allowed to flow downwards from the right into the center.

This is achieved by applying mains voltage to activate the coil of the solenoid pilot valve so that high pressure gas is introduced into the slider chamber from the left.

This allows the pressure on the right to be relieved via the central main connection at the bottom, causing the slider to move to the right. Pressure drops are always important when it comes to dimensioning valve systems.

Neither of these considerations is so very critical for four-way valves. Minimal pressure drops on the pressure or suction side are not a problem for four-way reversing valves, because the slider mechanism that actually switches over the valve is driven by the pressure differential between the high-pressure and low-pressure sides of the refrigeration plant. This is the obvious approach here because this type of valve is located at the interface between the high and low pressures, which is not normally the case for the valves in a conventional dry-expansion heat pump that the external pressure.

The actual pressure drop between, say, the refrigerant inlet and outlet on the suction side is therefore not crucial to reliable valve function.