Heat Pump Installs with Long Lines Technical Questions

beenthere

So now its just the inspector. No actual code numbers that you can site/report to us.



Yes, really, 90°F plus air from a heat pump in heat mode when the outdoor temp is below 40°F.

A York 3 ton YZB has a temp rise of 23°F at an indoor temp of 70°F and an outdoor temp, of 30°F. So yes, its has a discharge air temp of 93°F.

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beenthere

A York E1RD036S06 has an air discharge temp of 90°F with an indoor temp of 70°F and an outdoor temp of 30°F. The E1RD is a first generation builder's grade R22 13 SEER heat pump first made in 2005. It runs an evap sat pressure of 42 to 46 PSIG, which is a sat temp of 19 to 22°F. The sat variation is from line set length variations, and indoor air flow variations. Installed a lot of them.

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RoBoTeq

WHAT? Why wasn't I told?! This is some unnacceptable !

hvaclover

I tried to tell you but you were busy

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Not Stupid, Just slow

ironpit

i am new to this website and have been reading the dialogue between "been there", "robotech" and the" rep2jy" guys. I have been in the hvac business for only 10 years. I am nowhere near either of these guys when it comes to hvac. I wish I knew just 10 % of what any of them knows. But that is my reason for being here, today, for the first time. While my previous expertise was not hvac, I did excel in other things.I am a little disappointed in one of the parties, as both his facts and professional demeanor eventually succombed to pressure. His story line resembles my youngst daughters; who is still in college. I am not young. I have worked for a few hvac companies in Indiana, and everyone says that I am good at residential and commercial hvac. Some of the companies have tried to rehire me. My personal opinion is that my lack of hvac knowledge is appalling. I study, ask questions of other techs and surf the net. I know few, if any, hvac people in this area, that are up to what I consider the level that should be required. From proctors cheating at test areas, to things that can only be imagined, I am disappointed in the quality. I know there are professionals out there, i just haven't met those top tier guys. I am hoping to learn from the pros on this site and to them I am very grateful. But to those who are just blowing, logic itself is a trade and discipline that some us of take great delight in. We weigh not only the facts, but also the vehicles in which they travel. Please, if you don't know something, don't pretend. Just be kind enough to preface your opinions with a qualifying intro. After all that, I would like to agree that the initial inquiry was dismally addressed. As for all the blow about heat pumps, it is common practice to run heat pumps in Indiana, at well below 40 degrees. We use dual fuel or heat banks as back up.The systems work well without calling for backup down to around 20 degrees, depending of course on the design of the house and system. And we don't start at 0 degrees in the house. Once the temperature is up to set point, we leave it on(with all due respect to programming) and the heat pumps due fine. I am not saying that everything that we do is right, but it works pretty well here in the real world. there are some real good hvac people here, I just haven't met the top tier ones, but of course at my level, its' logical I shouldn't. Which is why I am on this web site. thank you, to the good ones

beenthere

Welcome to the site.

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ironpit

thank you for responding. I would like to state an observation or two about a situation and would appreciate your reply. I will skip a lot of facts and details, as your experience will most likely fill in the blanks. I am a small contrtactor who also helps a couple of dealers in central indiana. One of them drives me insane with all of his corner cutting.He has40 years in the business and is highly regarded. he is also a great guy to work with.When we change from 22 to 410 systems, he rarely changes the linesets, some of which are long and, I know, have oil in them. I have spoken with him about the issue, but he doesn't see it my way. I know it depends a lot upon how much oil is present, but how long is it going to take to break these systems down. It isdriving me crazy. We work for some high profile people. When this equipment starts failling, I will be associated with it too. also, I am currently helping him finish up the duct in a very high profile building. The metalduct is next to the roof (it is a commercial flat roof bldg). I am in in time to run the flex. The metal is done. The metal is not insulated and the returns will be pulling from the collars off the duct- no duct to return in the grid. All the return will pull through the egg crate panels. I know the temps ar going to range from an easy 125 just below the roof to 110 just above the ceiling. Is it going to be possipble to cool that building below 80 f and also not have sweating duct. The building is an office environment. If it matters, there is twelve feet above the ceiling and ten below. I am concerned. Please respond.

beenthere

If the returns are pulling in the hottest air. Won't be much if any sweating, since the supply duct won't be very cool. And won't be below dew point. As far as will it cool the building? Depends on how the system was sized. If they planned on the cooling of the ceiling, it will, if they didn't, it won't. Plenum ceiling returns should be outlawed. Makes installation easy for us. But has too many pit falls down the road.


As far as line sets. If blown/purged out properly, should never be enough mineral oil left to harm a R410A system.

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