coldroom working presure with r404a?

[stathis]

hi ,my system works with r404a the temp is between 0/2 celsius. i have problem with ice on evaporator.the sight glass fills completely and i have a defrost system with heaters working every 8 hours for 10 minutes.thanks for anh help and keep it cool!

[taz24]

hi ,my system works with r404a the temp is between 0/2 celsius. i have problem with ice on evaporator.the sight glass fills completely and i have a defrost system with heaters working every 8 hours for 10 minutes.thanks for anh help and keep it cool!


Hello..

Every 8 hours for 10 mins might not be long enough or often enough.

Change the time to every 6 hours for 20 mins and
see what happens for the next few days or week and see if it clears
and then stays clear, if it does you could set it to every 6 hours for 10 mins.

Do you know if the defrost has any form of termination?? What type of
clock / controler controls the defrost?

Because it is heaters you don't want the heaters on too long
so you need to ballence it correctly to defrost with the minimum amount of heat being added.

taz

.

[goshen]

same post twice???????????:rolleyes::rolleyes::rolleyes:

[stathis]

if i set the the expanding valve counter clockwise one turn do you think that this will be better for the coil not to ice up??

[Brian_UK]

Do NOT touch the expansion valve, it is fine.

[Magoo]

Have you considered an air defrost cycle. It is the fine art of setting the low pressure control switch to suit the system application.
magoo

[stathis]

when the system starts the coil seems to ice up...during the winter with the same settings it was working fine.humidity has rised because of the weather and now i dont know how to solve the problem.the coldroom is for meat,i have placed the temperature sensor near the door and set between 0-2 celsius.the compressor cuts with solenoid and then pump down.i noticed that close to the coil the temp is 2 degrees lower than the position of my sensor.do you know the best position of the sensor in the coldroom??because i maybe running to low and thats the problem of icimg up.thank so much for all your replies!!!

[Magoo]

Hi Stathis.
I would be putting the temp control sensor in the return / air on to evaporator, then set up the LP controller to cover iceups.
For fresh cut meats 0'C > +2 'C seems low and would tend to dry out the meat product.
magoo