TSSU-60-24 troubles

[arnoldbta]

I am new to this site and would like to take this opportunity to provide a little background about myself. Although I am just a beginner in the refrigeration side of service, I have a little over three year experience servicing commercial restaurant equipment. I have had my universals for a little over two years now, bu have always passed refrigeration issues on to other companies. Alongside my current job, I am taking 20 hours a week in night classes to get my hvac/r degree. I will be done with these classes after this next spring semester. After I finish school I intend to look into getting different certifications.


So please, if I say something that does not make sense, or I am just totally on the wrong page on something feel free to correct me. Just try to as kind as possible..LOL!!

So far on my resume of refrigeration repairs I have:

1: repaired leak on true beer cooler and changed filter line drier
2: replaced low-temp control (timer initiate) and filter line driers on two different ice-o-matic ice machines. A 400 and a 500HA. Both machines sprung leaks in the control itself.


These repairs seemed to go pretty smooth and have not had anymore issues. They took longer than I would have liked, but I am still in the learning stages on this stuff, and try to take my time to hopefully prevent any mistakes I could make if I tried to rush them.

Now to the main reason for my post. My latest refrigeration issue is a TRUE TSSU-60-24. I was called out for a beer box and a prep table not cooling at the same location. Bad condensor motor on beer box, changed motor and issue was resolved.

The prep table on the other hand was a different story. All fans were working,compressor working, all par containers in top of box were in place, but I was only getting like 55 F across evaporator in box. Ambient temp was around 77 F. First thing I noticed was how dirty the condenser was. Thought this could be the issue so I cleaned it, but it did not help any. I was not getting heat to my condenser coils to be released. Compressor was extremely hot.

With my leak detector and bubbles I was able to locate a leak in the liquid line coming out of condenser. Added access ports, recovered charge, repaired leak, replaced COPPER SPUN filter drier, pulled vacuum (under 300 microns and held), then recharged. Did not fix problem. Through some advice I read on these forums I cut old filter open and found it to be gummed up with a black powder.

Next step cap tube!!!! All I can say is "you have to be kidding me." I will not even go through all the steps I did to change this thing. I put in a 032-cap and did away with copper spun filter. Did not fix my problem.

When removing old cap tube I noticed a black tar substance coming out of it when I heated it up, so I was pretty certain I found my problem.

I have a compressor on its way, as I am unable to build head pressure when covering condenser or stopping fan motor. My pressures with the correct charge are 8 on the lo side and 75 on the high. Only way to build head pressure is if I unhook high side hose and flash what's in my hoses on the low side, having the condenser fan stopped. Restart fan and I am right back to square one.

I am replacing compressor because that is what true and i believe is the problem. Anyone know of another things I can check. Any and all advice will be very helpful. It will be Wednesday of next week before I go back so please just let me know.

Thanks in advance

Brandon

[icemeister]

Welcome to HVAC-Talk!

It sounds like your new cap is plugged due to that contamination of the oil in the system. If there's no refrigerant flow, you can't build head pressure.

The contamination comes from the overheating caused by the dirty condenser coil. The first thing you have to do is thoroughly clean up the entire system. I suggest you remove the cap tube and filter-drier and flush the evaporator, condenser and all piping with an RX-11 type flush.

Normally I would do a good oil change of the old POE oil in the compressor, but in this case the black goop contamination appears to be rather extensive, so your safest bet is to do the cleanup and then go ahead with the new compressor and another cap tube.

[dorvs]

i would aslo add a O-52hh capt t drier

[arnoldbta]

Thanks to icemeister and dorvs for the advice. I did go with the 052 filter like recommended. And although I hated to do it, I did replace cap tube and flushed system as recommended as well. Worked like a charm after all was said and done.

Another question though. Can anyone explain the best way to access the cap tube and evaporator on this unit? And are all prep tables this hard to access this area? If this is the case for all units I do not see how warranty replacements would pay off for the service company.

Thanks again for the advice guys..

[Capz]

Thanks to icemeister and dorvs for the advice. I did go with the 052 filter like recommended. And although I hated to do it, I did replace cap tube and flushed system as recommended as well. Worked like a charm after all was said and done.

Another question though. Can anyone explain the best way to access the cap tube and evaporator on this unit? And are all prep tables this hard to access this area?
.

Brandon, confused with your question. didn't you already replace the cap tube on the True deli server? I'd agree, very hard to access.

[icemeister]

Thanks to icemeister and dorvs for the advice. I did go with the 052 filter like recommended. And although I hated to do it, I did replace cap tube and flushed system as recommended as well. Worked like a charm after all was said and done.

Another question though. Can anyone explain the best way to access the cap tube and evaporator on this unit? And are all prep tables this hard to access this area? If this is the case for all units I do not see how warranty replacements would pay off for the service company.

Thanks again for the advice guys..

The TSSU60-24 has a full size top opening as I recall so it shouldn't be too difficult if you're resourceful.

I remove all the top pans, shelves, shelf brackets, back panel and coil cover to expose the coil. The coil cover is usually stuck on with about 5 lbs of silicon caulk so I heat it up a bit to loosen it up and the cover pries off easily.

Then I lift the coil up about a half inch and gently pull it out away from the back of the box. Then you have easy and clear access to the business end of the coil.

Some models have smaller openings (or none at all if it's an undercounter fridge) so then you need to remove the top. That's just a matter of a couple of screws in the top of each door frame, cut the butyl rubber seal around the perimeter and lift if off from the front.

[arnoldbta]

Brandon, confused with your question. didn't you already replace the cap tube on the True deli server? I'd agree, very hard to access.

Yes I did.. twice. I ran it some after changing the first one and changed it again since I had to remove it to flush the evaporator. Both times it took a considerable amount of time to get access to where I could remove cap tube. Was just wondering the best way to get access to that part of the evaporator.

[arnoldbta]

The TSSU60-24 has a full size top opening as I recall so iti did the shouldn't be too difficult if you're resourceful.

I remove all the top pans, shelves, shelf brackets, back panel and coil cover to expose the coil. The coil cover is usually stuck on with about 5 lbs of silicon caulk so I heat it up a bit to loosen it up and the cover pries off easily.

Then I lift the coil up about a half inch and gently pull it out away from the back of the box. Then you have easy and clear access to the business end of the coil.

Some models have smaller openings (or none at all if it's an undercounter fridge) so then you need to remove the top. That's just a matter of a couple of screws inut the butyl rubber seal around the perimeter and lift if off from the front.

I did the same as you except did not think to heat silicone. And removing the cover and cleaning all the old stuff off is the worst part. Do you use a heat gun to heat the caulk? And can you just reheat it when you reapply the cover?

Also when you remove the whole top and break the butyl rubber seal, is that butyl rubber something you just reapply with a caulk gun or something?

Thanks again for all the helpful advice you have provided me so far

[trippintl0]

The open top True's are pretty easy, say compared to the TPP pizza box with the evaporator on the side!! Naturally the cap tube is on the far side of the evaporator so you literally have to crawl inside the box or its impossible to work on it otherwise...!!!

[arnoldbta]

The open top True's are pretty easy, say compared to the TPP pizza box with the evaporator on the side!! Naturally the cap tube is on the far side of the evaporator so you literally have to crawl inside the box or its impossible to work on it otherwise...!!!

I am guessing the TPP pizza box is made by true also? I will make sure to steer clear of them lol. I was actually hoping I would never have to change a cap tube, or access another one on a box like this. Yet if I am going to be running into these situations, it will be helpful to know the best way to approach them.

[2sac]

I am guessing the TPP pizza box is made by true also? I will make sure to steer clear of them lol. I was actually hoping I would never have to change a cap tube, or access another one on a box like this. Yet if I am going to be running into these situations, it will be helpful to know the best way to approach them.

Tell the customer they need a new box and to stay away from True and Delfield. LOL True boxes are garbage.
Removing the silicone is the hardest part of the job. Also the accumulators are notorious for leaking. Evap coils should start leaking after 7 years or so if the box is stocked with veggies.
Best way to approach them? Set up a maintenance contract and keep the condensers CLEAN! If your customer has the box jammed in a space with no air flow, wire the condenser motor hot all the time. Blow the coils out with CO2 quarterly. I have also installed 115v fans to help exhaust the warm air.

[itsiceman]

I did the same as you except did not think to heat silicone. And removing the cover and cleaning all the old stuff off is the worst part. Do you use a heat gun to heat the caulk? And can you just reheat it when you reapply the cover?

Also when you remove the whole top and break the butyl rubber seal, is that butyl rubber something you just reapply with a caulk gun or something?

Thanks again for all the helpful advice you have provided me so far

When you start messing with the cover that is part of the way the condensate drains and needs to be put back like you found it or you might develop a leak Taking the top off is the easiest way IMO but you'll probably give the customer a heart attack when they see it apart

[icemeister]

I did the same as you except did not think to heat silicone. And removing the cover and cleaning all the old stuff off is the worst part. Do you use a heat gun to heat the caulk? And can you just reheat it when you reapply the cover?

Also when you remove the whole top and break the butyl rubber seal, is that butyl rubber something you just reapply with a caulk gun or something?

Thanks again for all the helpful advice you have provided me so far

Yes, I use a heat gun to get the silicon to loosen up. Sometimes it helps to use a small putty knife, but generally I just pull the coil cover off.

The silicon will stay stuck to the back panel so you don't need to reapply any new silicon when you reattach the coil cover.

The butyl rubber is in the caulk section of the hardware store and comes in a tube for a caulking gun. I like to use GE brand.

[icemeister]

When you start messing with the cover that is part of the way the condensate drains and needs to be put back like you found it or you might develop a leak Taking the top off is the easiest way IMO but you'll probably give the customer a heart attack when they see it apart

You must be thinking about the fan plenum which is below the evaporator coil on the True prep units. Yes, those are part of the condensate drainage and there's rarely a need to remove one of those...except I have seen a lot of them rotted out where the plenum seals to the bottom pan, creating some bad condensate leaks. Then I simply get them warm & dry and reseal with lots of silicon.

[itsiceman]

The exception is what I'm talking about the whole coil gets wet and in some cases the water tracks.
Where the two sections meet is a tiny lip the coil shroud sits into the lower fan shroud and the back and front need to be back to normal or headache.

I have just bend the top of the plenum lip over (without breaking any silicone and slide the coil up a bit (sits loose in the plenum) and hit it from the front easier but I still think its better to just pop the top so you don't need to pull shelves or outer cover with those crazy screws, scratching the interior paint up and bust your back in the process

Trust me will stink less when you're done this way too since your not sitting in all the muck