Medical Equipment Weathers the Storm

Posted Tuesday, 12 September 2017 11:06 by Martin King in Process Chiller Blog

With so many natural disasters hitting the U.S. lately, one thing’s for sure…..medical facilities don’t have time to shut down. But how do hospitals and clinics pull it off during Mother nature’s disasters?

Unfortunately, climate related disasters are becoming a more frequent common reality for communities all over the world. But don't worry, most hospitals are preparing to meet these disasters head on!

Troubleshooting an MRI Machine

Posted Wednesday, 06 September 2017 20:33 by Martin King in Process Chiller Blog

There are many different issues that can cause problems in an MRI machine.  Here are a few of the most common problems faced by MRI technicians.

MRI helium level is low:

If your MRI machine is alerting you about the helium level most likely its because it hasn't been monitored as it should be.  It could also mean that there is failure somewhere in your cooling system, causing the helium to burn off too fast. 

If this occurs, schedule a fill immediately!

Power Outages:

If your system is glitching or shutting down, check the breakers. This problem usually occurs many times after bad weather or a storm, and can be resolved by resetting the breakers for the section of the building where the MRI machine is located. 

Since weather is unpredictable and breaker failure can occur at any time, it's very important to know where the proper breakers are located in your building. Getting your machine back and running quickly, will prevent a decrease in productivity. 

 Image artifacts:

Image artifacts are usually related to wear and tear of the MRI machine coils.  When image problems occur most technicians automatically think there is a problem with the components of the MRI itself, but it is actually the coils that are causing the issue.

In order to fix an imaging problem you will have to ship your MRI coils out for off-site repairs.  MRI coils are relatively easy to repair andurnaround time for this type of repair is rather quick. Some repair providers will also offer loaner coils that will keep your machine up and running while your coil is getting repaired. You should inspect the condition of your MRI coils frequently, and talk to your service provider about having a field engineer do the same during your regularly scheduled preventative maintenance checks. Sometimes if a problem is caught early enough, the MRI coil repair can be scheduled around a time of lower patient activity.

Heat exchanger temperature errors:

If the water pumping through your system is too hot, your MRI machine will lock-up and stop scanning until the temperature can be brought back down to specified levels.

Make sure you know who you should contact for help if this happens. A good place to start is the heat exchanger. First check to see if its LCD display is lit. Many models also have breakers on them, so check to see if the breaker is set. Next, check the incoming water line. The water should be about the same temperature as a drink coming straight out of a refrigerator. If your heat exchanger’s LCD is not lit and tripping the breaker has no effect, the problem is likely in the component.  If this is the case you should contact your MRI service group immediately.  A good way to prevent this problem is to perform regular check-ups for your chiller.  Many MRI service contracts include preventative maintenance on a quarterly basis. 

The most important thing to remember if your MRI machine has a problem,  is that it’s not the end of the world.  There is always a solution to the problem. You just need to know where to look for help.

*For questions or assistant with your Legacy Chiller contact us anytime at legacy-chillers.com 

Caring for Your Process Chiller

Posted Wednesday, 30 August 2017 10:39 by Martin King in Process Chiller Blog

Everyone knows the most important piece of equipement for a brewery is its cooling system.  In order for any brewery to run smoothly and keep producing more of the beer we love, the brewery's chiller must be working to its potential.  Here are a few important tips to remember when servicing your process chiller.

Inhibitors are a must:

Glycol is the most important part of a chilled water system.  Why you ask? Glycol allows fluid to be chilled without freezing.  Inhibitors keep the glycol and chiller running smoothly.

Take daily water samples:

Corrosion can happen anywhere in a chiller system, so it's very important to test samples of the water from ALL locations of your chiller.

Don't forget the pH levels:

pH level readings are part of every routine water sampling.  A bad pH level can have a negative impact on a chiller's performance, and can shorten its lifespan.  Recommended pH levels should be between 8.0-8.5.  If your pH levels are off it could mean you are not using enough glycol.

Flush your chiller after installation:

As soon as a new chiller is installed, the whole system should be flushed immediately to ensure the fluid is completely free from contaminants with no debris or surface contamination present to cause damage to the fluid, the pipework, and the new equipment.

Have a question? Just ask!

If you're not sure how to maintaint the process chiller at your brewery, or think it might not be running up to its potential contact an expert.  At Legacy Chiller Systems we provide 24/7 assistance for all of your chiller questions.  Visit us at www.legacy-chillers.com

Are Economizers for Process Chillers Getting Missed By the Engineering Community? Just Maybe?

Posted Tuesday, 29 March 2016 14:42 by Martin King in HVAC Business

Guilty As Charged

Yes, I am obviously an advocate for proper application of economizers for smaller (1-20) ton process chillers. I have a lot of friends within the mechanical engineering community that just about all say, "Wow, that's a great idea!" (as in, you go Martin!)... Yet, when it comes to specifying an economizer for a smaller process chiller, they gloss over the subject. Every once an a while I get the, "Well, the end user does not understand what an economizer is, so they will not pay for it." Good grief I say!

For those of you who do not know me, I have been tinkering with application of economizers on smaller mission critical chillers since the early 2000's. As I experimented with the concept, it just seemed smarter to reject process heat to the outdoor air, or a water source in the case of a water-cooled chiller, rather than running traditional mechanical refrigeration at a much higher cost and net environmental impact. As my design evolved into a potentially viable market opportunity,  I applied for and was granted a broad scope US Patent for process chiller economizers in 2007. Yay for me, you say?  Frankly, I would probably not do it again, and that's another story :-)

Getting To the Point

With my appreciation for brevity, and to prevent the aforementioned gloss over, I will pick one of my favorite real world applications as the focal point of this post.  

For some time now, medical imaging and treatment systems, such as MRI, CT, PET and LINAC, have been in our sights.  Namely their 24/7 operation, high readability requirements and relatively high chilled fluid set-points (that range from 55-65F) make these systems a particularly good fit for our economizer technology. With some good old fashion cold weather, generally an abundant commodity throughout the northern USA and Canada, the math points to some some attractive ROI's even the most conservative bean counters have a hard time passing up. 

Before we jump into the math, let me share a very basic sniff test that could stop economizer consideration cold: To be financially viable, the operating environment must provide at least a ten degree (F) difference between the economizer cooling medium (generally this is outdoor air in the case of an air-cooled condenser chiller or a water in the case of a water-cooled condenser chiller) and the process fluid servicing the load. For example, if your site is located in Phoenix and your process requires 45F, application of an economizer just does not pencil out. 

Lets Crunch Some Numbers, Shall We?

 In this example, we will use Legacy's economizer audit tool, available for download from our KB, to analyze ROI and see if the additional investment in economizer technology pencils out.

Some Data Points For Our Analysis

Our customer is looking to replace an existing process chiller for a GE Signa 3.0T MR750 MRI. Legacy's OEM solution for this MRI is a PZAT18D (15 ton) process chiller. Our target site is located in the greater Chicago area, and the MRI site prep documentation calls for a process approach temperature ranging from 55-65F. For the purpose of this review, we will pick a process approach temp of 60F.  Considering the old chiller is located outdoors, the customer plans to run 40% glycol concentration to prevent freezing. 

After talking with the hospital administrator, we have learned that their power rate averages .10 per kilo watt/hour and we also have taken the time to research the breakdown of how the hospitals utility company generates their power. This is generally represented as a mix of nuclear, hydro-electric, and fossils fuels. 

Lets Do the Numbers

First, we need to input the site data. Below is a screen shot of the data we collected from our target zip code for the city of Chicago. 

Next, we will input the proposed equipment data. This data was taken from the Legacy submittal on the PZAT18D model chiller available for download on the our site. 

Next, lets have a look at the potential economizer savings. This screen indicates a potential annual "Operating Cost Reduction of $5,350", with an equivalent annual CO reduction of 3,331 LBS.  

Lastly, we will have a look at the all mighty Return On Investment (ROI). This screen indicates a potential ROI of .84 months. Important note, the "Nexus upgrade costs" indicates the added end user NET cost to add Nexus Technology to a standard process chiller.   

In addition to the potential energy savings and related CO reductions, an economizer (via Legacy's Nexus Technology) also reduces wear on a chillers mechanical refrigeration system. This reduced wear has the potential to reduce service and maintenance costs over time. 

For more information on process chiller economizers, Nexus Technology, or to get a copy of Legacy's energy audit tool used to perform the above calculations, contact Legacy Chillers @ 877-988-5464 x 101. 

Lastly, on  Tue, Apr 12, 2016 9:00 AM - 9:45 AM PST, Legacy Chiller Systems is hosting a webinar titled "Nexus Process Chiller Technology - Introduction" - Click here to sign up today