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What is suction pressure and discharge pressure?

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Answered 2010-02-19 05:38:45
Answer: The terms suction and discharge are the terms refer to hydraulics. In hydraulics if the the liquid has to be lifted or pumped to the usage area the hydraulic pump will be used . This pump will have to functions that is first suction to lift the fluid and the discharge or delivery . The familiar words in pair are lift and discharge; suction and discharge. The specification of pump for these terms are suction head and discharge head.Answer

The suction pressure refers to the pressure of the referigerant being "sucked" back into the compressor. The suction pressure is a critical variable in ensuring the accuracy of the refrigerant charge, along with the tepmerature of that line as well. The "superheat", or heat added to the vapor in that line can be monitored in this manner.

You have not mention which suction pressure... Actually Where ever the suction is presented that pressure is called suction pressure.... and suction pressure in practical cases normally always less that atmospheric pressure and in case of delivery pressure it is opposite

Saying that suction pressure is " the pressure of the referigerant being "sucked" back into the compressor " is not accurate.

Simply , the suction pressure of a pump is the absolute pressure of a fluid , measured at the inlet of the pump ( in your answer , the pump is the compressor , and the fluid is whatever refrigerant. )

The discharge pressure , is the absolute pressure of the liquid measured at the outlet of the pump.

Obviously, the discharge pressure is usually bigger than suction pressure.

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No, the liquid (discharge) line is the high pressure side. The suction line is the low pressure side.

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On the discharge line with the relief of the pressure control back to suction

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Sounds like a blockage in the system on the high pressure side.

Why is used the balancing line in boiler feed pump and its direction of flow?

In boiler feed pumps usually the discharge pressure is 20 to 30 times tie suction Pressure so to protect the pump balancing line is given from discharge to suction.

What happening when you are overcharging an air conditioning with freon?

discharge pressure is high, suction pressure is high superheat is low and subcooling is high.

What is compression ratio in air compressor?

The compression ratio is simply the ratio of the absolute stage discharge pressure to the absolute stage suction pressure.

How do you calculate suction pressure for air theoretically?

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Why air condition compressor is overheating?

IT COULD THAT YOUR SYSTEM IS EITHER OVERCHARGED OR UNDER CHARGED. ALSO CHECK YOUR FURNACE FILTER.AND MAKE SURE YOUR OUTDOOR UNIT is clear of dirt and obstructions. --------------------------------------------------------------- There are several reasons for a compressor to overheating High compression ratios are the result of either lower than normal suction pressures or higher than normal discharge pressures. Changes in suction pressure will affect the compression ratio more rapidly than changes in the discharge pressure. For this reason, it is important to keep the suction pressure at its highest possible value. Causes of low suction pressure can include incorrect sizing of components, misadjusted or defective metering devices (TXVs), loss of refrigerant charge, plugged driers or strainers, and excessive suction line pressure drop. Although not as sensitive to change as the suction pressure, the discharge pressure can still greatly affect the compression ratio. Keeping the discharge pressure within normal operating conditions is still important. Causes of high discharge pressure can include dirty condensing coils, undersized discharge line, a blockage or recirculation of condenser air, erratic condenser fan operation, refrigerant overcharge, noncondensibles in the system, and an undersized condenser.

Why is the suction line of a pump larger than the discharge line?

It is common practice to specify the pump suction line one size larger than the pump discharge line in order to increase the Net Positive Suction Head available (NPSHA) to the pump. A smaller suction line the same pipe size as the discharge line would result in more pressure drop in the suction line and reduce the amount of head available to the suction side of the pump. This in turn would result in an operating point closer to cavitation of the pump.

What should the high and low pressures be for 404A refrigerant on a freezer?

18-20psig suction 250-270 psig discharge In freezers pressures are ok .I got it ,but the mention pressure of suction 18-20 discharge 250-270 at what temprature in centegrade it should be.

What is suction and discharge head?

These are terms used by refrigeration and air conditioning techs. The suction is refrigerant returning to the compressor from the evaporator, or the low side. The high side is the discharge or head pressure, where high temperature high pressure gas leaves the compressor to flow into the condenser. These systems should only be worked on by licensed and experienced techs.

What causes suction?

Suction is caused by an are of negative pressure.

Comparration diameter size of suction and discharge?

The diameter of the discharge line leaving the ac compressor would be smaller than the suction line, because the compressed gas in the discharge line is more dense.

What is the science behind suction?

Suction is the reduction of pressure to create a force. In the instance of liquid, suction will cause the liquid to transfer from an area of higher pressure to the area of lower pressure.

What is the difference between pump design pressure and pump differential pressure?

Let me differentiate first between design pressure and mechanical design pressure. Design (or discharge) pressure is the pressure at the outlet of the pump, the pressure you've designed the pump to deliver. The mechanical design pressure is a value that the pump casing and downstream piping have to be able to withstand as a minimum*. I presume you mean design pressure as discharge pressure. In this case, differential pressure is the difference between the discharge pressure and the suction pressure (the pressure at the inlet of the pump**). * this is calculated taking into account that a pump would be working against a 'blocked discharge' or a closed valve in the outlet piping ** imagine a reservoir filled with liquid

Where is the low port on a 1987 Volvo 240 DL air conditioning system?

The low pressure port (Suction) and the high pressure port (Discharge) are both located on the back side of the compressor.

What is the fan speed relationship to suction pressure?

for a given air conditioner: the faster the condenser (outdoor) fan the lower the suction pressure. the faster the evaporator (indoor) fan the higher the suction pressure.

What do you mean by head of pump?

Total pump head is the sum of suction and discharge pressure in mtr. ie. 1 bar =10.33 metres of water column

Does low suction pressure have an effect on reciprocating compressors?

At very low suction pressure, the suction valves of reciprocating compressor will not work and there will be no gas in the cylinder during compression stroke, resulting some damage to the suction valves. If low suction pressure trip protection is not provided there can be some abnormal damage.

What does antisurge valve do in compressors?

The compressor antisurge valve opens to bypass flow from discharge to suction. This allows the compressor to flow through bypass and keeps the compressor from surging (reverse flow thru compressor). The discharge pressure does not continue to build due to closed discharge conditions.

Why your hvac haye high suction pressurehigh discharge pressure?

Dirty condenser coils, high outdoor temp and heavy indoor load if coils are clean. Overcharge.

What is the definition of reciprocating pump?

a pump consisting of a piston that moves back and forth or up and down in a cylinder. The cylinder is equipped with inlet (suction) and outlet( discharge) valves. On the intake stroke, the suction valves are opened, and fluid is drawn into the cylinder. On the discharge stroke, the suction valves close, the discharge valves open, and fluid is forced out of the cylinder.

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