Compressor reliability

[auser]

I am planning a purchase of two -80deg freezers. I am looking for advice as to reliability, especially compressor reliability. I am replacing a freezer that killed 4 compressors over 7 years and gave constant other problems that caused gain of temperature (fan harness plugs etc etc).

Any positive comments on compressor manufacturer or type, service ease/frequency, quality of manufacture, important issues to evauate beyond $/cu ft?

My number one need is reliability

Thanks in advance for comments.

[rocket]

a freezer that kills 4 compressors means you
have had an improperly designed or improperly
maintained system or it was misused.

all currently manufactored compressors are very
reliable. You need to search for a reliable
contractor not for lowest price.

[rimek]

ThermoElectron now has some major market share. Their main brands are Forma, Kendro(revco, harris), and Jouan. The Formas are nice to own and service, they're $$$, but they have a value line(900 series).
Forma & Kendro- mostly Copeland
Jouan- Danfoss
Thermotron is another brand that has units using semi's
(k-bodies)

What is your application and cabinet size need?

Chest or upright?

With A freezer that goes through that many service issues, it is important to check ambient conditions, and utilities applied as well as service organization performing the work.
It sounds like something wasn't done right.
Were any of these failures under warranty?
Were all the compressors on one stage or both?
What brand did you have?

Most mfrs are using the copeland 1HP for 23 cu ft and down, but now that bristol is producing fractional low-temps again, who knows? There is a particular import(starts with 's') that i would not recommend.

An ultra-low doesn't kill compressors all by itself, and any brand is susceptible to improper service technique.

[rimek]

Why are posts being bumped off the "active" list so fast?
I replied to this and within 10 minutes, it's off.

[frozensolid]

I don't know much about these ultra low temps, but if I bought one I would want some kind of suction accumulator installed.

Find a company that specializes in selling and working on these things. The average joe mechanic will be lost working on them. If no specialist's are available find a heavy refrigeration company, and hope they will work on it. Be ready to pay high dollar, or the compressors wont stand a chance.

[condenseddave]

Originally posted by rimek
Why are posts being bumped off the "active" list so fast?
I replied to this and within 10 minutes, it's off.

Where is this "active list" that you're looking at?????????

[rimek]

ddave,
on one machine, it's "view today's active threads"
on another, it's "view new posts"

[auser]

Perhaps the first two compressors were stressed by low voltage (102 instead of 120) but the freezer had a built in voltage regulator to take up the slack. I then installed a voltage booster, but lost two compressors after that. Air circulation was fine and filter was always clean. One replacement compressor was under warranty still when it failed. Three compressors were one stage the fourth the other stage. Was a Harris. Have to check the numbers but think was 14-17 cu ft

Why not use an import (starts with s) since they are now making their own compressor presumably for reliability?

Also considering New Brunswick based on company reputation though these are very pricey.

My service company specializes in ultralow temp machines and service the universities and hospital labs in the area. Supposed to be very knowledgeable. However do not want to ever have to make service calls for say 5 years at least. Is that unreasonable?

Still Copeland vs Bristol vs Danfoss vs S?
220 vs 120 V? (17 cu ft)
1 hp enough?

[rimek]

The 3 on one stage- low or hi?
Even Harris shouldn't have had that much trouble, I still think something wasn't done right.
The import and the domestic you mention-you can use your own judgement, I wouldn't choose either, but to each his own.
A positive thing about 220 is that you will more likely get a good service in an institutional setting.

5yrs w/o service? possible but these units should be evaluated annually AT MINIMUM.

still, chest or upright?
what region are you in?

[auser]

3 on first stage, I think it was a lemon

Chest

SE USA

Still confused about how to choose for reliability....

[nce-comp pro]

IF YOUR CONCERN IS COMP.FAILURE AND YOU DON'T MIND SPENDING A FEW DOLLARS MORE USE AN OPEN DRIVE BELT DRIVEN SLOW RPM 900 TO 1100 IT WILL RUN FOREVER.

[rimek]

I know the point is moot regarding the harris, but 3 hi stage comps is really irregular as their load and refrigerant are more normal/common for compressors, especially for a chest cabinet. I wonder if your service org. tried using another mfr to drop in for the bristol(OEM). Anyway, if you let me know your region or facility, I may be able to hook you up with some references/clients that could shed some light on this for you. As I said, I've had few problems with the Formas(regular and value line). What brand did your service org. recommend?

[auser]

I am in FL

My service org recommended one of the import"S"

I do not know what they were using for replacements but they had to replace one on their warranty (less than a year).

VWR sells freezers that are made by Forma and I guess are identical in quality?

[rimek]

I'm not a salesman but I know that the VWR line has 3 grades, the signature and regular are forma units, the value line is revco. The vwr private label also adds 1 yr to warranty(parts&labor) instead of forma 1 yr.

edit: yes, the freezers are the same quality as the standard formas and revcos. Be sure to check utilities in your place. Are you the only one having issues like this w/ultralows?

[auser]

utiities have been an issue, most with long wire runs use boosters at the freezer

Since most manufacturers use the same compressor (copeland I guess) it doesn't much matter if they are put together using good sense

[rimek]

boosting or "voltage compensation" is not meant to be a 24/7 thing- get the long wire runs/utility problems resolved before you spend any of your grant $$ on equipment(if applicable). Long wire runs exist all over, wiring needs to be sized to compensate for voltage drop, especially on motor loads. You mentioned 102 volts on a 120 volt unit, or 85% of listed and rated-not good for motors.


edit: yes they all may use the same mfr of compressor, it's the controls, cabinet, manufacturing practices, and interstage heat exchanger design which set them apart.

Good Luck 2 U

[kerndt]

Auser
I have serviced the ultra low market for the past 26 years. Being a factory authorized service representative for 22 years. I agree that your service company would be suspect. Even if there are external problems at your facility, your service company should have advised you of them and made correction before putting the freezer back into service.

The big players in the market today are Thermo Electron (revco, forma) and Sanyo. I know these systems in great detail. Their both very reliable, they both have specially designed compressors. I think you will find the Sanyos pricing is better. There warranties are equal.

Thermos has had some compressor failures, do to suction reed failures, and failures due to the oil separator, where it fails to return the oil to the compressor. Sanyo, years ago really only had problems with the oil separators, now they manufacture their own, were Thermo still uses the same separator that has been prone to fail.

Sanyo control system has been very stable; Revco has had problems with their control system, with failing cabinet sensors and heat exchanger sensors, also had accumulator tank failures. Forma has problems with failures do to high operating pressures, they have retro-fitted there systems with expansion tanks.

[auser]

Thanks for that reply. That was the kind of info I was looking for. I did hear some complaints that Sanyo's were hard to work on...alot of disassembly to get to the problems?

I have already placed an order with New Brunswick Scientific for two units. In the end I made the decision based on an upfront 5 year parts including compressors warranty without a surcharge for that and of course these units were competitively priced with Sanyo etc. The compressors are Aspera under the Embarco name. My experience with other New Brunswick equipment is very good with regard to reliability and stout construction and this weighed heavily in my decision ...ie reputation even though the company is relatively new in freezers.

Any comments other than a "good luck"?

[cyro]

I've worked on the Revco's for a few years now. and yes I have replaced alot of accumulator tanks lately.

I love there equipment but! this year they doubled my price on there OEM compressors. I refused to pay double and it broke my heart to put a standard compresser in but I did.

This was my first time I felt bad doing a job and I know it just won't last as long as the OEM.

I told the lab it was not as good, but they signed off on it.
Revco told me I must attend there school for $****** to get a 50% discount on parts.
I know they where just bought out, but this is not right.

[bryan l]

I have worked on Sanyo's in the past and I must admit that I dont have MUCH experience with other manufactures but I can tell you the Sanyo line as of a few years back had some problems that they have since resolved. They had a run of Temprite Oil separators that had floats cracking or leaking and you would get oil logging in the evap and in some cases low stage comp failures due to no oil return. Yes the Sanyo's are a pain to tear down BUT you should not NEED to tear one down, when and if you do the extra 15min it takes to pull it apart is no big deal. The Sanyo Rep for our area was great when I had to deal with him and I was able to get parts quite quick. Sanyo has ALWAYS used their own compressors, They make 80% of all domestic fridge's on the market and have a HUGE compressor plant of their own on site. I personally think that the Sanyo line was not bad at all, The construction is solid and the method and application of the service tools (temp probes) incorporated in the -80c freezers are helpful.

THE KEY is to find a company with the right mechanics. You cant rely on the "Company" You need to find out how much the individual mechanic knows and what their experience is. Ultra Low mechanics need to have patience, able to think outside the box some times and take their time. Proper procedure is essential.


Your problem with power I would say is your only major problem, Compressor manufacture is not your problem. The best compressor in the WORLD wont put up with the voltage problems your facing. Where are you using this freezer? every lab and hospital I have ever worked in has some of the BEST power monitor and rectifiers money can buy. This some drug lab set up out behind a 7-11 in a trailer stealing power from overhead power lines?

[kerndt]

Auser, I will say good luck, because I have very little exposure to the New Brunswick ultra-low. I have three of them so far in my service area, and only one failure, (oops that a 33% failure rate) just kidding. My initial opinion of the Asprea compressor is, it doesn’t rank that high on my compressor chain, and the 2nd stage system seems to operate under extreme conditions. Meaning operating pressure are high, due a warmer than normal heat exchanger temperature. They set the cut-in temperature for the 2nd stage at -18 C, where Revcos cut-in is -38C and cut-out at -18C. So five year warranty is a good thing.

I will say to you as I say to all my customers, “It will fail” and how are you going to know. I recommend using external an alarm with 24 hour monitoring, so someone can contact you. ( oh and test that alarm system regularly).

New Brunswick does build some heavy duty equipment, but their not that great in refrigeration of any kind. They are the new kid on the block in the ultra low market, and they have a lot to prove.

The unit I worked on was under warranty, and the factory service rep was very helpful and more than willing to do what ever it took to take care of the customer, and they paid me very well.