cabinet icing up

[petewa]

hello fello fridgeys,
i have a self contained critically charged salad bar that i have replaced the condensing unit on and cut out the liquid reciever which is constantly icing up over a period of days. there is a dixell xr20 controller in place set to cut in at 4 and out at 2 (manurfacturers specs) there is no weight on the label and i have charged the system to run at 52psi suction pressure and roughly 270psi head pressure on r404a. the liquid line feels great and there is nice sweat coming back on the suction line. the cabinet easily achieves temp and cycles well but it continues to ice up. :mad:
any advice would be greatly appreciated as i am having night terrors :rolleyes:
cheers

[paul_h]

Critically charged but had a reciever?
Critcally charged but you charged to a certain pressure?
Sorry, none of that makes any sense.

Is it a self contained unit or remote condenser?
Is it a cold plate or fan forced?
What are the controllers defrosting setpoints?
Did you fit the same type of condensing unit?

[dogma]

I have never seen an iced up reciever. The sub cooling must be insane.

An Accumulator will ice up, that's why they have drain trays, burn off trays and/or are insulated.

Get out your PH chart and do a system check. Check sub cooling and super heat. Air flows over condenser and evap.


If the reciever is iceing up there is something a miss.

Isn't there?



_dogma-

[petewa]

sorry guys i meant the evap coil is constantly icing up

[Gary]

You say you replaced the condensing unit.

What happened to the old one?

Is the new one an exact replacement?

Or a little larger?

[Mobbsy]

Petwa,

I will begin by interpreting several factors you have stated in a different manner to the other posters, firstly I think what you are saying is that you have replaced a condensing unit ( it would be excellent if you could say why) and have had to cut the receiver out, which was factory fitted, because the existing refrigerant metering device is a capillary tube.
I am assuming once you have re-commisioned the saled bar, a number of call backs have occurred due to the evaporator icing up 'which is constantly icing up'. There is no way the receiver is icing up while my ass is pointing to the ground.

Just provide a little more information and I'm sure you will begin to receive some productive advice:
Old condensing unit type and model....
NEW condensing unit type and model....
R.M.D......
Evaporator type.....
Controller defrost settings........
Open salad bar? Deli type?

[Mobbsy]

Petewa,

Sorry mate I just read your short post correcting yourself, that the evaporator is icing up, but you still need to provide a bit more information.
I would like to know if there is any difference between the old and new condensing units, control settings, evap type(finned-natural or forced convection) e.t.c.

[750 Valve]

Pete who manufactures this cabinet?

As requested previously need to know if you are talking forced/induced draft or natural convection finned coil.

Silly question but is there a TXV? If there is then why no receiver?

Where is the Dixell stat measuring its temp from, return air, supply air, cabinet temp, coil temp?

How many defrosts per day and what duration?

What temps are you seeing and where are you taking them from?

Got any pics?

Whats the superheat and subcooling when case is close to desired temp?

Cheers

[Mobbsy]

You look and sound familiar 750 valve.

[750 Valve]

perhaps... ever worked in pub and club Mobbsy?

[Mobbsy]

That I have, the moustache was a dead give away. Your identity is safe with me big fridgie. Sales and service, it just feels like yesterday.

[750 Valve]

Mobbsy my how the years fly - good old sales vs service skirmish, the bongo van from hell (column shift OYB512) and the smell of an old pub's cellar - or the bars for that matter

BUT....

Watch out looks can be decieving and if you go by my avatar pic I haven't been up for air since July 2001! Next time I see you at ARBS you better buy me a beer if you can get away from those TAFEies :D

Its certainly a small world, I know petwa too (whether he realises it or not I don't know) - who posted the original question too but he seems to have disappeared for a while, maybe it got the better of him :p

[Mobbsy]

The years go by too quickly, and the unique aromas of a cellar never leave you.

No air since 2001! Well some do say snorkels are handy over a wide range of situations, and you provide a convincing argument supporting this notion.

I will buy a you beer for sure, but if we see each other before ARBS, I'll be certain to shout you a shandy (middi of course).

[Magoo]

750 valve
Your aviator. question ? whose groin are you smothered with, I think I can recognise it.
magoo

[nike123]

750 valve
Your aviator. question ? whose groin are you smothered with, I think I can recognise it.
magoo

By smell or coiffure? I don't smell anything! :confused: