Trane heat pump metering device

[roofdude]

Packaged heat pump model# wcd180b400ea

On the indoor coil the liquid line exits a 1/2" drier then increases to 7/8". On the end of that 7/8" pipe are the cap tubes that feed liquid to the coil in cooling mode. I cut the 7/8" line at about the half way point thinking I could blow nitrogen through the tubes from that point. To my surprise I found a bunch of shiny cap tubes inside of the pipe I cut. What is this? Did they run the cap tubes through the 7/8 pipe to protect them like a conduit or is there some other purpose for this? Thanks

[james mo]

They are using the 7/8 inch pipe as a distributor and the cap tubes are pushed through an inch and a half so they do not get filled will sil-fos while brazing. Another member here ...Paysonhvac...used to make these type of distributors to upgrade orifice coils to TEV coils. Apparently a Trane engineer thought he could save some money using that setup since it worked for Payson.

Hey Payson, did you ever get credit for the design?

[roofdude]

Ok. So the tubes are pushed into the 7/8 pipe from liquid line towards coil or from coil back towards liquid line drier? The end of the 7/8 pipe where the tubes exit does look like a distributor now that you mention it. Thanks.