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jptor
05-06-2020, 07:53 AM
Hi Guys,

Friend of mine posted this video: https://youtu.be/wK_nnuH69E0
His first ever YT appearance hence he is bit nervous... :)

I wonder what you think and if you would like to see more videos like this?
What is good in the presentation and what would you improve?

Looking forward to hear from you!

Glenn Moore
05-06-2020, 04:01 PM
These videos are very good but need a little more information about field problems and what problems can occur if the valve installation isn’t correct.
1) 1 very good point shown
2) 2 points not so good

Good Point
The valve connected directly to the distributor, with the distributor leads exiting out the bottom of the distributor, with the distributor in that position the liquid / gas mixture will produce a liquid puddle in the distributor to get a good distribution into the cooler (gravity effect) whereas many cooler manufacturers mount the distributor in the upwards position which causes a u bend from the expansion valve outlet downwards then back up into the distributor, this can and does cause poor liquid distribution and poor frost banding across the cooler

Bad points
1) the equalization tube brazed into the suction header is too low a could become filled with refrigerant and oil compromising the valves operation (hydraulicing). Always put the equalisation pipe into the top of the suction header/pipe so that only has vapour gets into the equalisation pipe. The equalisation line is a signal pipe only,
there is no flow, so if oil or liquid can enter the equaliser it will stay there
2) the indoor unit shows the bulb mounted with its capillary tube exiting from the bottom of the bulb. The capillary tube must always exit from the top of the bulb as some TEV’s have a limited charge in the bulb and if the bulb is mounted with the capillary tube exiting from the bottom then the charge in the bulb can free drain from the bulb causing poor valve performance mostly applicable with MOP barged valves

These videos are a great training aid but the opportunity to help diagnose valve and system installation and operating problems could increase the students knowledge gained from these videos tremendously
Sven has so much background knowledge and problem solving on expension valves that he could do a training video on the dos and donts in conjunction with this one
Good job Sven ����