The Homemade Heat Pump Manifesto

[S-F]

Pour a concrete slab over it. It can be really difficult to keep hydronic heaters from making crazy noises.

[AC_Hacker]

Originally Posted by Vern2

...how do you stop the creaks, pops. cracks???

Vern,

PEX expands and contracts a surprising amount due to temperature variations. The rule of thumb is 1" per 100' per 10 degrees F.

If you bury your PEX in a concrete slab, there will be ZERO sound, end of sentence. This is because the concrete is so strong that the PEX expansion becomes internal to the tubing.

If you do a staple-up or sandwich type of floor, there is opportunity for sounds.

Normal (non-barrier) PEX has a rather slippery surface, so expansion is smooth and gradual, no popping.

'Oxygen barrier' PEX has a coating on the outside of the PEX (usually colored) to prevent the migration of oxygen into the tubing. This coating does not (at the time of this writing) have the same low-friction characteristics as PEX and upon temperature changes, it can grab and then suddenly slip (especially so when aluminum spreader-plates are used), keeping travelers in NM motels awake during the night.

PEX-Al-PEX has a PEX inner layer, then an aluminum layer, then a PEX outer layer. The aluminum prevents oxygen migration and the PEX outer layer has low-friction characteristics, so no grab-and-slip sounds in the night (or day).

So, the solution is to use PEX in slab (any kind of PEX), or else use non-barrier PEX or PEX-al-PEX for built-up or sandwich or underfloor.

* * *

When I re-plumbed my house, I used PEX (both plain PEX and oxygen barrier PEX) throughout. The sound of hot water beginning to flow through the pipes certainly was an issue. Then I struck upon the idea of slipping short segments of very thin-wall HDPE that I has slit, over the PEX where it went through a hole in a stud or plate.

Free, non-stick expansion restored, Problem solved.

-AC_Hacker

[S-F]

Originally Posted by AC_Hacker

Vern,



When I re-plumed my house, I used PEX (both plain PEX and oxygen barrier PEX) throughout. The sound of hot water beginning to flow through the pipes certainly was an issue. Then I struck upon the idea of slipping short segments of very thin-wall HDPE that I has slit, over the PEX where it went through a hole in a stud or plate.

Free, non-stick expansion restored, Problem solved.

-AC_Hacker

That's a clever idea there AC_Hacker.

[tweeker]

Newbie here.

I have been lurking and reading this thread for several months now, so I thought it was about time for me to chime in with some of the experiments I have been doing in my so-called "ME TIME" for the last several years.

Just wanted to say hello, and what a GREAT thread this is.

DIY, home owner economically practical and money saving resume includes:
Wind Turbines, Evacuated Tube Solar hot water, Geo-Thermal, Heat Exchangers, Amorphous Solar Panels/Cells, and hacking A/C units and turning them into heat pumps is my hobby area of experimentation.

AC Hacker should be getting a publisher in line so they can write a book about this pioneering adventure :-)

Regards,

Tom

[AC_Hacker]

Originally Posted by S-F

That's a clever idea there AC_Hacker.

We all come up with a few clever nuggets.

Problem is how to share them. EcoRenovator is so good for that.

-AC

[AC_Hacker]

Originally Posted by tweeker

AC Hacker should be getting a publisher in line so they can write a book about this pioneering adventure...

This whole effort, this whole thread is a kind of sustained exercise in 'giving back', or maybe more correctly, 'giving forward'. I've tried to demonstrate that with gumption and a few tools it is possible to do some amazing energy efficient things with junk. I think that gumption and inventivness is in our DNA, it just needs a wake-up call to get going.

I don't think that everything needs to be monetized to be valuable. I do believe that there is tremendous worth in a 'commons', whether it is a public park or a public library, or a free on-line public information pool, such as EcoRenovator. I think that this value goes beyond merely having a place to get free info, but also includes the recognition that we can work together and share and in this way, everybody wins.

If writing a book, maybe on the order of The Idiot's Guide to Volkswagon Repair would help in this effort, then I would do it.

Originally Posted by tweeker

DIY, home owner economically practical and money saving resume includes:

• Wind Turbines
• Evacuated Tube Solar hot water
• Geo-Thermal
• Heat Exchangers
• Amorphous Solar Panels/Cells
• hacking A/C units and turning them into heat pumps

Tom,

Sounds like you are indeed, a kindred spirit. I'm looking forward to seeing photos, and learning about the details of your efforts.

...don't keep us waiting!

Regards,

-AC_Hacker

[randen]

Funny I wouldn't know why a concrete floor would make noise. Here with 1700 sqft heated is completely silent. The only sound we hear is the compressor on the heat pump and thats hardly detectable.

Randen

[tweeker]

When I have time to figure out how to post pictures I will do so.

Whole forum seems to be sort of a "Kindred Spirit".

I have a full time job (Parenting) a part time job (50+ hrs a week working) and if there are any waking hours left over, I get a few hours a week of "ME TIME".

My hobbies are also my "Mental Health Therapy Sessions" :-)

Of course my children (14 & 16) like to tinker with this green stuff also, they get the benifit of good grades on their school science projects, and looking like little GREEN geniusses.

I don't let them physically hack A/C Units though, they prefer watching ME get ZAPPED anyway :-) Although they have been mildly zapped many times by the solar panels/cells, scorched by the solar evacuated tubes, and seared by the heat exchangers. But when it comes to REAL electricity, and HIGH pressure refrigerant filled lines, I don't have enough confidence in their abilities to do it safely yet. Besides they have already fried about 4 or5 multimeters on the solar photovoltaics & batteries, cheap ones, but never the less.

There are some things I have learned from hacking A/C units and converting them into heat pumps that could benefit people, So in time I will find the time to share what I think is of interest and/or significant. My motivation to start hacking A/C units, was in a way, a means to bypass monopolized HIGH $$$$$ Geo-Thermal HP market.

Gotta get back to my part time job.

Tom

[AC_Hacker]

Originally Posted by tweeker

When I have time to figure out how to post pictures I will do so.

Somebody asked the same question just yesterday. I posted this, maybe it will be of help to you.

Originally Posted by tweeker

My motivation to start hacking A/C units, was in a way, a means to bypass monopolized HIGH $$$$$ Geo-Thermal HP market.

Quite right. I even paid some goodly bucks to attend a GSHP Professional's seminar, and the 'monopolized HIGH $$$$$' message was certainly there to be seen.

But, I also think that if GSHP ever became really widespread, economy-of-scale and competition would come into play and prices would drop... alot.

In the meantime, we just have to do it ourselves, and save the big bucks.

Originally Posted by tweeker

There are some things I have learned from hacking A/C units and converting them into heat pumps that could benefit people

This is the very thing I'm hoping for, that people like us will publicize the things we've learned and that will encourage others to do the same. Andy Warhol said something like, "we all get our 15 minutes of fame." Well I think that we also have an ability to see the '15 minute sized' obvious solution that no one else quite saw before. It doesn't mean that we are a genius, but enough of those kind of insights can become pretty significant... maybe even a game changer.

Regards,

-AC_Hacker

[sparkchaser]

Hello, all!
I haven't been able to read EVERY post, but hav read a lot of them. My question is: Has anyone successfully used an air-source heat pump converted themselves to ground-source? I consider myeslf OK at HVAC, though mostly repair, not installation of other than package units. I'm also pretty mechanically inclined as well as a qualified journeyman electrician who has also had a little formal HVAC schooling (many years ago!). I live just up river from ACHacker. Comments?? Especially from ACHacker?