Liquid level regulating valves Types PMFL200 and PMFL300 Danfoss valves

Liquid level regulating valves Types PMFL200 and PMFL300 Danfoss valves Function

When the liquid level inside the float drops,the float orifice opens. This relieves the higher pressure, ps, acting on the servo piston to the low pressure side causing the PMFL to open.Variations in liquid level will result in variations 

The setting spindle, pos. 60, has not been set from factory. It is imperative that the setting spindle is adjusted before the valve is put into operation. The outer spring, pos. 23, is preset and the inner spring, pos. 43, is adjusted when in pressure over the piston and variation in the

amount of liquid injected. It is important to choose the correct spring set when designing the plant. The spring set should be selected from the

table below:turning the spindle. The following tables shows the adjustment of the inner spring in number of turns of the spindle as a function of valve size, spring type and pressure difference.

Liquid level regulating valves Types PMFL200 and PMFL300 Danfoss valves Design

The values for spindle turns are an indication for an initial setting only. If a position indicator is used, a more precise modulation can be achieved when fine tuning the valve setting. If the PMFL is not opening fully, the spring tension must be reduced. If the PMFL is operating in a ON / OFF function, the spring tension should be increased.The condenser pressure will have an effect on the fine tuning and large variations in condensing pressure might call for readjustment.The subcooling is measured just before the PMFL and the pressure difference is for the valve only

excluding piping and armatures.The PMFL can be used together with SV 4 as a pilot valve.The final choice of orifice may vary depending on refrigerant and pressure levels. Smaller pressure levels needs a bigger orifice. Pressure difference levels below 3 bar (43 psi) need SV 4 – 6

with ?3 mm orifice.PMFL function example SV 4 can be used for PMFL low pressure control system. The float must be connected as shown.Note: Only one inlet connection possible for SV 4. SV floats for PMFL The orifices determines the K v (C v ) value of the pilot and the following table can be used as an initial selection guide.

Liquid level regulating valves Types PMFL200 and PMFL300 Danfoss valves Ordering model

Valve type

Code no.

EN GJS 400-18-LT

PMFL 80-1 027F3054

PMFL 80-2 027F3055

PMFL 80-3 027F3056

PMFL 80-4 027F3057

PMFL 80-5 027F3058

PMFL 80-6 027F3059

PMFL 80-7 027F3060

PMFL 125 027F3061

PMFL 200 027F3062

PMFL 300 027F3063

Valve type

Code no.

EN GJS 400-18-LT

PMFH 80-2 027F3065

PMFH 80-3 027F3066

PMFH 80-4 027F3067

PMFH 80-5 027F3068

PMFH 80-6 027F3069

PMFH 80-7 027F3070

PMFH 125 027F3071

PMFH 200 027F3072

PMFH 300 027F3073

PMFH 500 027F3074