Sperre air compressor lp safety valve blowing pressure 15 bar normal pressure is 8 bar hp valves and gaskets new

It is what the max pressure is to handle before the safety valve can have if it concept is for 10 bar then you have a 10.5 bar safety valve or if its 8 bar its 8. . 8.5 look at the tank itself its in most case there you can read what it can handle.

2 possible actions to have to get what can blow off. 1. there is something dirt or corrosion in the check valve if its blows out on the pressure relief valve its under on the black hoseline right on the pressure switch point 2 . it can also be the safety valve will open if the pressure is adjust set to high. or like CONTIMAC compressors has often this problem. 8 bar safety valve on a 8 bar adjusting is very tight taken on factory then you will lower the adjustment to over 7bar max thats most times the max presure for airtools !! or replace a good choice with 11 bar = 159.5418 psi safety valve if thats the point .then its solved.


Another fix in an failure when is when there are metal parts are used there can be metal parts come of out of a membrane or another metal part that and come between the check-valve on the tank where you must clean the metal pieces the relief of the pressure switch remains on a rusty metal particle in the non-return valve

This number is for the D20114 its the safety valve that can not be set to a max basic pressure .
its strange but its not adjustable it can be defect i have one time the same the experience there is not a adjustable Pressure Switch on this model , the moast compressors have a 8 to12 bar adjustable.pressure switch.
Very important This safety valve gives an electronic brake between the pump and to a end of top about 10 bar . if its not switching off then a drain valve opened . and blows all the air out. (but only over 10 bar ) the max pressure on the tank , the moast tools are working on a pressure from 6 to 8 bar.
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Checking Safety Valve
WARNING: Risk of bursting. If the safety valve does not work
properly, over-pressurization may occur, causing air tank rupture or
an explosion.
Before starting compressor, pull the ring on the safety valve to
make sure that the safety valve operates freely. If the valve is
stuck or does not operate smoothly, it must be replaced with the
same type of valve.
Draining Air Tank (Fig. 1)
WARNING: Risk of unsafe operation. Risk from noise. Air tanks
contain high pressure air. Keep face and other body parts away from
outlet of drain. Use safety glasses when draining as debris can be
kicked up into face. Use ANSI S12.6 (S3.19) ear protection as air flow
noise is loud when draining.
NOTE: All compressed air systems generate condensate that
accumulates in any drain point (e.g., tanks, filter, aftercoolers,
dryers). This condensate contains lubricating oil and/or substances
which may be regulated and must be disposed of in accordance with
local, state, and federal laws and regulations.
1. Ensure On/Off switch (A) is in the OFF position.
2. Move compressor into an inclined position so drain valve (H) is
at the lowest point (this will assist in removing moisture, dirt, etc.
from air tanks)
3. Place a suitable container under the drain valve to catch
discharge.
4. Grasp black lever on drain valve.
5. Slowly rotate lever to gradually bleed air from air tank.
6. When air tank pressure gauge reads 10 PSI (275.1 kPa), rotate
valve to the fully open position.
7. Close drain valve when finished

Air leaking air out of intake when the compressor is not running and pressure in tank indicates bad check valve. Follow the discharge tube to where it connects at the brass valve mounted to tank. This valve is a non-return valve and can be replaced with generic valve. When air blows or pulsates out of intake as the compressor is running is indication that pump has bad valves or blown gasket/ gaskets. Good luck

IS this a 175 psi unit. What was the safety valve psi that was replaced. I recommend removing the heads and checking the valves. Suspect you will find one of them bad.If safety is past the hp head remove and check hp valves first. If safety is after lp head check it first. I have seen and lp valve break and pieces carry over to the hp side. So if lp valve bad you may want to inspect the hp side also. Good luck!

From want you are describing sounds like the high pressure valves are leaking in the HP Head. there are 2 safeties on this unit . If the safety that's lifting is between the low and high pressure cylinders it's hp valves leaking. If the tank safety is lifting at 50-60 psi It should be replaced. It is a 200 psi safety.

Very rare to have problems with rings. Blow-by would produce high pulsating pressure in the crankcase causing oil to blow out the oil filler plug/ dipstick. If normal crank pressure, suspect problem with valves or gaskets. Remove air filter cover and check for air blowing out of intake or very hot head or air discharge tube. Leaking valves or blown gasket will cause low volume/ low pressure and hot discharge air. Remove the in-tank checkvalve and look for carbon deposits /debris build-up. If the checkvalve and the interior or discharge hose are coated with oil deposits /carbon, most likely problem is valve plate/ gaskets /head. Good luck with your repair.

Does the compressor have enough CFM to run the printing machine. Will the compressor build up pressure and shut off if you close the discharge valve at the tank. Your printing machine may simply be using to much air. If the above items are not the case you may have a faulty check valve in the receiver tank or valves going bad in the LP or HP heads. The valves may also simply have carbon build up or dirt of some type not allowing the valves to seat properly. I would start at the check valve. One way to check the check valve is to see if you have air blowing from the bleed off line at the pressure switch all the time. Another way to check is loosen the fitting at the High Pressure head an see if you have air blowing continously. Caution do not remove the fitting at the head completely. If the check valve is bad you will have high pressure air blowing until the receiver tank is drained.

Did you inspect lp and hp valves. I would take a close look at the HP valves first,typically bad Lp valves will cause it to build pressure very slowly.

There is a check valve between the compressor and tank, and there is also an 'unloader valve' which blows the pressure off the compressor so that it starts under little load. I think your check valve is stuck open and the unloader valve is blowing tank pressure off.. and when the compressor tries to start it's starting against the pressure in the tank.

So check/replace/thaw the check valve and you'll be good to go. It's generally at the tank where the line from the compressor head goes into the tank, it'll be between the two somewhere.

lp