Hi, all

thank you, US Iceman, to open this sub-forum. It is very interesting.....

all this started here:

http://www.refrigeration-engineer.co...7631#post57631

Quote Originally Posted by Brad
..... What started out as a discussion on lowering head pressure and it’s implications has become a discussion on total system optimization! And it seems to be a topic that a lot of people are interested in. With the ever rising costs of energy and the push for a greener planet, I wonder if this would make a good topic for a forum or sub-forum.

What Sergei mentions about defrosts going from twice per day to once per week has become quite typical in plants that incorporate smarter controls and/or keener operators. Evaporators that require 2 defrosts per day during that one hot week in august can often get away with one or two defrosts during the winter months. This gets back to the problem of fixed setpoints often being the “worst case” setpoint. If two or three defrosts are needed in the summer, that’s where the pins are left in the time clock. If -25 suction kept the rooms cold in August, that’s where the suction is left all year. If one evaporator requires 145# for defrost, that’s where the pressure switches are set. It’s obvious that a lot of systems have a lot of room for energy usage improvements

Another great up-side to long durations between defrosts is you can float the head pressure lower for a longer period of time thus enhancing energy savings.
Yes, I have to agree there is a lot of room for energy savings by usage improvements, but....

we are witnesses to the war between companies to get the job (speaking here mainly about industrial installations of either HVAC or refrigeration plants) using methods with no scruples to gain profit. They are ready to reduce the price, quantity, quality, everything to get the job and to sell sh*t with words "we are selling the best energy savings technology, innovative energy savings system, fully automatic energy savings system no needs for operators, maintenance.......and so on.


On opposite side we have our customer, usually without any knowledge (except acceptable price) about quality energy savings system also often short in budget, but looking for a good plant.

Many times this "innovative" technology "innovators" sell with very high prices too yes, to the people with unlimited budget but with very limited brain.

Nice bait/snatch for sharks around.


How to win in that war? How to sell good designed, optimized plant, usually expensive to customer buying only cheap things.

We cannot win if we cannot stop global heating and climate changes with waste energy and very soon there will be only loosers on this planet.

What do you think where to start? What to do?

Best regards, Josip