Compressor/condenser Location in Small Store

[ME27272727]

Hello. Is it common to see food case remote condensers and compressors located in basements of small grocery stores / meat markets? I've seen this more than once now, and can't understand why you wouldn't put all of this equipment outside or on the roof. These basements lacked proper ventilation and would easily reach over 100 degrees F from all the heat rejection.

 

[EnergyProfessional]

common among places that like their compressors to fail....

No, it should reject heat to the coldest place, which is ambient. unless those basements have some need to get heated.

 

[willard3]

It is typical but a bad design.

 

[ME27272727]

Ok I wasn't sure if I was missing something. I've seen basements with small 600cfm exhuast fans trying to ventilate a space with 10 tons of refrigeration being rejected to it. I'm waiting for the day I see a split system cooling these basements that are full of condensers.

 

[lukaiENG]

I'm almost ashamed to admit I've done this before! however in my defense I did look at the condenser heat load vs the exhaust rate and worked out a delta T. (which was reasonable!)

 

[urgross]

What happens when (if) the refrigerant line breaks in the basement? I would send a parrot in first, or maybe a lawyer.

 

[lukaiENG]

how is this any different to any other refrigerant coil (evaporator or condenser) in a large open space? refrigerant gases are only an issue above certain concentrations. a small condenser in a large space is not going to kill the canary.

 

[urgross]

I must have missed the mention of "a large open space". Maybe I was confused by this being applicable to a "small" store.

 

[EnergyProfessional]

doesn't matter if the basement is large, over time it will get warm. Even if the basement is 10°F above ambient, you have significant more compressor work.
Even if the condenser is outside and you don't have enough clearance (i.e. multiple condensers put in one roof corner), they die sooner. Plus the waste of cooling performance and energy.

The only remote reason where the basement would make sense if they need to run the condenser in winter but don't have a low ambient rated system. but then they just chose a bad system.

 

[chicopee]

But in the winter time, the condenser will warm up the basement.

 

[berkshire]

Ok Winter good , summer bad.
B.E.

You are judged not by what you know, but by what you can do.

 

[ME27272727]

Basement is unoccupied. And now you lose the benefits of low COP with cold ambient temps in the winter. I just don't see any reason to think that basement condensers are acceptable in small grocery stores.

 

[berkshire]

Whilst stuffing condensers into basements of small grocery stores is not a good plan, there may be other factors at work.
Small stores tend to be in areas where housing density is high such as inner cities. You may have a narrow alley at the back of the store with traffic.
The proprietor may elect to put the condensers in the basement to avoid damage from motor vehicles. Also some but not all inner cities tend to be high crime areas, the condensers may be inside to reduce theft. Having to reject 10 tons of heat from a tiny basement may be a better alternative to having your stuff stolen by copper thieves.
B.E.

You are judged not by what you know, but by what you can do.

 

[EnergyProfessional]

berkshire; good points, i didn't consider that.
ME27: you should make sure ventilation rate is sufficient. you can calculate how much heat is rejected (cooling tonnage + compressor power) and make sure airflow is large enough to have the basement stay not above 5°F above ambient. Maybe a differential thermostat could modulate or cycle the fans.
Make sure you don;'t just exhaust, but also bring in OA. If you don't provide makeup air, it will suck air out of the building and depending on crack size may not be able to exhaust as much as you need.