Tafco Walkin question

[Capital12]

Good Morning Folks, First, i am not really tech savvy with HVAC.

Question: i have a Tafco Walkin in Refrigerator for my restaurant which was purchased roughly 12 years ago. Compressor is located on the rooftop of building and was put there due to extreme heat and dirt in the air inside the restaurant. It was worked beautifully since about 2 years ago. Leak was found inside the box (inside the fan). It was repaired. Since then, i've had to have it charged about every 3 months, as it appears there is another leak. HVAC tech is telling me that it has to do with the valve not opening for the Gas to get into the system (Low pressure gauge) It appears that i have a problem when the temperature outside has a drastic change (ie: from 70 degrees to 40 degrees overnight) . This happened 2 days ago when i came into work and the box had a temp of 46 degrees. it hovered around 50-55 degrees for about 4 hours, before pulling back to normal. Am i getting my chain pulled here, as i am getting tired calling a tech to come and spending $ everytime, or is the unit need to be replaced?

I appreciate any insite on this.

Thank You
Robert

[ryan1088]

By chance was this repair made in the summer time? Sounds like you may have another leak, or they didn't add the full charge back in. There is a valve that will open when the outside temperature drops to maintain head pressure, and when it does it starves the system of the refrigerant it needs. With the cost of refrigerant being what it is, you should really have the leak found and repaired!

[Tommy knocker]

Get a refrigeration tech. Could be another leak. Could be they didn't fix all the leaks to start. Could be charged by sight glass when warm out. Could be on and on and on. Get a refrigeration tech. How do you find a good one? Hint: he will not be the cheepest in the phone book. Good luck.

[pecmsg]

Where in NY?

[Capital12]

I am located on Long Island. I've already went thru 2 techs, and have over $$$$ invested in this since the problem started. Seems like they would rather drop gas into it, and keep coming back every 3 months.

[jpsmith1cm]

#1. Pricing isn't permitted. I edited your post.

#2. Once is a mistake. More than once is missing a leak.

Either the techs haven't repaired the leak or there is another leak (or leaks)

Adding gas every 3 months isn't normal or acceptable practice.

As to the problem with temperature swing, a good and knowledgeable tech can compute the proper amount of gas, add it and never have to come back.

I do it all the time.

[Capital12]

#1. Pricing isn't permitted. I edited your post.

#2. Once is a mistake. More than once is missing a leak.

Either the techs haven't repaired the leak or there is another leak (or leaks)

Adding gas every 3 months isn't normal or acceptable practice.

Much apologies. Thank you to all for your responses.

[pecmsg]

Three months is a long time but the leak still can be found.

Go to the contractor locator map:
http://hvac-talk.com/vbb/showthread....p&goto=newpost
and find someone that can fix it before more damage is done.