Freezer room condenser unit replacement at Ark Walworth Academy, Walworth

The site and the brief

Climate Flow Limited replaced the condenser unit serving the kitchen freezer room at Ark Walworth Academy in Walworth, London. The aim was to keep the school kitchen's food storage running with as little disruption to the school day as possible. Climate Flow carries out commercial refrigeration work across London and surrounding areas.

When the condenser unit fails, the freezer room cannot hold its temperature. For a school, cold storage is not optional: food businesses must keep chilled food at 8°C or below (GOV.UK, chilling and freezing), and the kitchen relies on its cold rooms to do that.

Scope of work

Replace and restart

1. Recover the refrigerant. The refrigerant was recovered from the system and the old condenser unit was removed.
2. Install the new unit. A new Danfoss condensing unit was fitted, with brazed pipe joints and electrical connections.
3. Leak test. The new joints and connections were leak tested.
4. Modify the evaporator. A new expansion valve and an oil trap were installed at the evaporator.
5. Bring the room down. The engineers worked extended hours until the freezer room temperature settled, to protect the stock stored inside.

Check and hand back

• Monitoring of the system's performance.
• A final inspection of the system and adjustments.
• Clean-up of the work area, leaving it safe and ready for normal use.

Equipment installed

We install and service Danfoss equipment, and on this job the old condenser was replaced with a new Danfoss condensing unit.

At the evaporator, a new expansion valve was fitted. A thermostatic expansion valve controls how much liquid refrigerant goes into the evaporator and protects the compressor from liquid refrigerant (Danfoss, thermostatic expansion valves).

An oil trap was added as well.

How do F-gas rules affect a condenser replacement?

A company that installs, repairs or maintains stationary refrigeration equipment containing F gas for someone else must be certified by an approved body (GOV.UK, certification for companies working on F gas equipment). Each engineer also needs their own qualification, and working with F gas without the correct qualifications is against the law and can lead to a civil penalty (GOV.UK, qualifications for F gas work).

Climate Flow is F-Gas certified, and the refrigerant on this system was recovered before the old unit came out.

The challenge and how it was handled

A school kitchen needs its freezer room back quickly. The plan was to do all the work that takes the system out of service first:

• refrigerant recovery;
• fitting the new unit;
• the leak test;
• the evaporator changes.

The engineers then stayed on site until the room temperature settled. Monitoring, checks and adjustments followed while the freezer room was back in use.

The result

The freezer room was brought back down to its working temperature and its performance was then monitored. After the final inspection and adjustments, the area was cleaned and handed back ready for normal use.

Related work

This job is part of our refrigeration repair and maintenance work, one of the services on our commercial refrigeration services page. Schools and colleges can read how we work around the school day on our schools and education page, and other jobs are on Our Projects.

If your freezer room or cold room needs a condenser unit replacement in London or surrounding areas, Climate Flow can survey the system and give you a no-obligation quote.

This guide is general information, not a survey or a quote for your site; every system is different, so an engineer needs to see yours before any work is priced.