North East Office: 01642 249026 Yorkshire Office: 01709 367001

Refrigeration Design with James Farrell

This week, our Refrigeration Design & Contracts Manager, James Farrell, did a quick interview with us in regards to refrigeration to break the ice…

How long have you worked in refrigeration design?

The genuine answer is since December 2016, however I’ve been within the company since 2008.

What are your first thoughts when you get a refrigeration enquiry?

Product… For example, if it comes in as “walk in chiller” my first question is always “What’s in the chiller? Will it come in chilled or are we pulling down to temperature? If so, how much and how long?” sort of thing.

I would treat a fresh fruit and veg chiller completely differently to a raw meat chiller, for example, it’s often mistaken that you size refrigeration plant on room volume, a 5m x 5m x 3m walk in veg chiller would have a different evaporator and condensing unit combination than a meat chiller. We specify this and hone in on optimal parameter.

Do you need to visit every site to do a survey or are you able to work from plans sent in by the customer?

We can always work on assumptions as long as I have some baseline information to carry out a solid heat load calculation, which would then be subject to site survey and design review. If I received an enquiry with some plans, I would send the customer a list of bullet point questions for the information needed to get something meaningful back.

What has been your favourite project to date?

My most rewarding project was Ascension Island, my favourite design was for a well-known food manufacturer, and my favourite overall project is Company Shop Leicester.

Could you give a bit of background information on the project – for example, how was it innovative? What environmental considerations were taken into account? Did it save the customer money because it’s energy-efficient?

Our customer operates two wax embalming lines, each had its own blast chilling cooling tunnels to set the wax before moving into a spiral chilling room.

With the increased demand for their product, they were looking for a way to run production 24/7 without having to stop at any point to cater for the required defrosts of the blast chiller evaporators. This would take each line down for 30 mins every 4 hours or so, therefore they also required better traceability of the air off temperatures into the cooling tunnels, and the airflow through the cooling tunnel required optimising.

As such, we came up with a completely bespoke design, adding a third blast chilling evaporator and connecting to the cooling tunnel ductwork where 12No. motorised dampers controlled by an RDM TDB programme would move to direct airflow such that when an evaporator required a defrost, the third evaporator would take over that line.

The user panel in production would prompt the operators for a defrost on a timer with a visual and audible alarm. The user would press defrost and the TDB program in the main control panel in the plant room would take over to make the changeover. The user panel then informs the operators with the same audible and visual queues that the defrost is complete and to switch them back and this can operate back and forth across the two lines 24/7/365 if required to do so.

The RDM TDB program allows us all information of air on, air off, defrost probe, coil in and coil out temperatures so we could really hone in on the optimum design. The customer can monitor the temperature of the air entering the tunnel, plus with inverters on the evaporator fans, we were able to dial back the airflow to completely optimise the efficiency up the full length of the cooling tunnel.

One week after commissioning and handover, the system went into full-scale Christmas production and ran 24/7 for a number of weeks intermittently for around three months and fully met its design brief.

For more information on refrigeration design and how it can benefit your business, give us a call on 01642 249026 (North East office) or 01709 367001 (Yorkshire office).