chilled water PHE

all dears.
good day

may you all please get me some suggessions for the following?

i have installed one PHE for chilled water generation and it was running fantastic for last 8 months .

but for last few days it is not giving proper and of course rated parameters.

the details of the PHE are as follows.

alfa laval PHE ( semiwelded NH3 to water application)
125 TR at the rate of 50 CMH and
water in = +8 Deg C
water out = + 2 Deg C
EPR of danfoss is installed to control the evaporation temp. at -1 Deg C
no oil is stuck in the phe or the surge drum.
compressor is giving a capacity of 133 TR at - 1 to +40 Deg C

the problem i am facing is
even the EPR is there ,the evaporation temp. is falling down to
-10 Deg C which i fear will cause the water to frost in side of the plates and will crack the plates.

i have carried the following activities.
1.cleaned the filter of the EPR
2.replaced the CVP
3.drained out the oil; but didnt get any oil trace in side of the system

i am expecting smoe kind of suggessssions from you experts.

have a nice time ever.

waiting eagerly,

priti:)

Hi, Priti,
Just I few quick sugestions.

1/Refrigerant charge
2/Expansion valve/level control problem
3/Reduced water flow due to dirt blocking a pump strainer
4/Damaged pumped.

I would try to establish pump flow rates on the Glycol/Brine side. If you have a flow meter on your system this is very simple, otherwise you are depending on commisioning data, such as temps in and out of the chiller and pump Amperes.
:) Regards. Andy.