View Full Version : Performance information on 1950's era York 20 ton chiller?

10-12-2013, 06:27 PM
HI All- I'm trying to do an energy analysis on the savings of replacing a chiller. After spending an hour on hold with JCI/York, they pretty much told me that they had no data. I need something to work with here. Does anyone have any idea where to start with data, or research? I've searched the ENTIRE web:p and can find nothing. I need something to base my analysis on that the utility will find moderately acceptable if I do indeed find significant energy savings. Ideas, info, other? Thanks Laura

11-12-2013, 02:59 AM
I am impressed the chiller is still operating, circa 1950. Classic equipment, built like a brick out house period, slow and easy will last for ever, seems it has.
Develop your own performance profile, energy absorbed versus cooling effect energy. I can only imagine everyone at York would have a blank look on their faces with your request /enquiry.

11-12-2013, 08:59 AM
You could data log the power input to give an idea of electricity consumption. You'd need to log the chiller performance alongside in order to get an accurate COP.
Almost seems a shame to replace such a historic chiller, if it's not costing a fortune in repairs.

11-12-2013, 06:20 PM
Well unfortunately it is winter, so there is no way to datalog useful information.

I'd love to build my own performance profile, but I can't just make it up. I have to have some source of information upon which to base it. What about a newer chiller, if I could come up with performance data from, say, a 1970's era chiller, maybe that would be useful. Even general chiller performance from that era, of similar size, might be justifiable. Where to go from here, to get to there?

11-12-2013, 07:02 PM
Hi Laura
Could you supply some details and photos of the unit it sounds very interesting.
As much detail of compressors, evaporators and condenser from data plates etc would be useful.

But you say its a 20 Ton chiller, if 1 ton = 12000 BTU/hr as a rule of thumb this should give you an idea on your cooling requirement for original design.

If heat load has been increased over the years you will need to add this load.

To size the chiller you need to calculate the delta T between the inlet and outlet water (the change in temperature), and the rate of flow in gallons per minute (GPM). Measuring the delta T requires a thermocouple. Check the water temperature of the water inlet line and the water outlet line, and subtract the numbers to compute how much heat the equipment is adding to the water.
BTU/hr. = Gallons per hr x 8.33 x ΔTF (h = cp*ρ*q*ΔT)

11-12-2013, 07:31 PM
Here's the nameplate data: YORK WATER CHILLER, MOD 2DH20E, SER 467-7364OT, REF R-22, 120 VOLTS, 200 PSI WITH PH 3 MOTOR, 20 TON, SER 50107820, MODEL H51SND-G, 208 VOLTS, 67.8 AMPS.

I have a pretty standard operational model (simply % load based on Bin hours) that the utility accepts. What I need is the performance of the existing chiller so I can calculate the annual kwh of energy it consumes, and then do the same with the new chiller. The difference is the energy savings.

I'm assuming the cooling load is the same. Even though chillers are often so oversized, this building is getting a new 2nd floor. I used those load calcs to estimate load for the existing first floor (with a % increase due to inefficient old construction) and then for the basement. I ended up with a higher load than the existing chiller, so I think it is safe to assume peak cooling load is the same as the chiller capacity.

I did find some interesting articles about chiller performance back in the 70's, one said pre 1980 was 0.72-0.8 kw/ton and the other says COP of 3.7. I'll start with those and see what I end up with, if it is even close to reasonable.

12-12-2013, 06:22 AM
Don't assume old equipment automatically is same as low efficient, they using R12, R22 etc. thermodynamic very efficient refrigerant but to days equipment only approved use R404A R407C, R410A, R134a [1] and they have lower theoretical COP to start with compare the old forbidden refrigerant

Low RPM reciprocal compressor in some size is very hard to beat i term of isentrop efficient if you compare for example modern high RPM scroll-compressorn.

Don't surprise after measurement and calculation if COP difference is very small or negative for new machine if you study cool circuit in term of temperature delta, area of exchanger, compressors isentrop efficient, refrigerants theoretic efficient, measured pressure difference etc. and mostly of COP improve in new machine over the old is coupled to better control and regulation, variable RPM of compressors, electronic TXV (ie. more efficient load regulation) and working more close to cooling demand. And don't forget, better insulation of cold store room can be better invest to take down electrical bill...

And can you promise 50 years lifetime without any replace of new compressors ??? ;-) - customer have this old machine running as free at least 30-40 year in the invest term and need quite big COP-improvement if saved energy pay of the new investment in reasonable of time.

Ie. often very hard to show energy saving in term of better COP can pay off new investment of new machine to replace already running, full working and already payed machine - differences is to small...

But is cooling demand doubled and old machine cannot handle this, machine not serviceable (in future) depend of missing part, cost or/and using forbidden refrigerant, is a different case and another decision point for invest cost...

[1] if you not want using HC-based refrigerant, HC-based refrigerant today is only way to make same theoretical COP as old forbidden refrigerant - none of days allowed HCF-based refrigerant in R4xx-series can beat HC in term of theoretic efficient, and R290 with suction exchanger is very close to R134a and beat R22 in efficiency for example.

And EU in next f-gas rules in few year future possible forbids mostly of R4xx based refrigerant as R404A, R410A etc. and R134a depend to high GWP-value (ie. have R143a and R125 in blend) and my guess they setting limit to max 1000 or 700 GWP (for example Dalking starting now in this year to sell R32-based heating pump as GWP 675 even this refrigerant is flammable - this is no choice in future but make machine safe enough to handle flammable refrigerant if want selling machine in Europa) and already now max 160 for car.

13-12-2013, 03:26 PM
you could do a snap shot of the efficiency of your chiller.
Climacheck offer a manual analysis on their website.

You just record the data required from your chiller and input it on the website and hit the calculate button.

Just be aware of the manufacturers data on the new chiller as it will not be a like for like comparison at the instant that you take readings unless you can match their selection criteria. You will always find new chiller has very good "quoted" operational figures.