Propane (R-290) for heat pumps? - Page 14

Xringer · 12-29-11, 12:27 PM

Oh, I use all cut and paste.. I normally go to far-out websites like Junk Science..
I liked this one.. The Chevy Volt makes more CO2 using electricity, than using gasoline would..
Detailing the greenwashed Chevy Volt | JunkScience.com

I guess stopping the CO2 from the Keystone XL pipeline (until after the election) will make up for the
extra CO2 from all those new Chevy Volt's GM is selling these days..

That was just another joke! The volt isn't really taking off..
But, it costs us a bunch, even if we don't buy one..

"one analyst puts the taxpayer cost at up to $250,000 per each Volt sold"
Time to End $7,500 Electric Car Tax Credit | National Legal and Policy Center

It's an insane world we live in today. If I didn't have a sense of humor*
about our situation, I would have to disconnect the Fios, halt my news paper
delivery and stick my head in the sand..
Or, become a hermit living in the woods, off the grid..

*
Humour - Wikipedia, the free encyclopedia
"The hypothetical person lacking a sense of humour would likely find the behaviour induced by humour to be inexplicable, strange, or even irrational. "

BradC · 01-15-12, 09:47 PM

Ok, some practical experience.

In Australia we don't have "heat pumps" (we do, but we call them reverse cycle air conditioners).

I have 2 Window A/C units (both reverse cycle) and my car A/C running on R290.

The car A/C is actually running a 60/40 mix of Propane and Iso-Butane (pressures are close to R12).

Both window A/C units are running on straight Propane.

I've not taken detailed measurements, therefore my evidence is strictly anecdotal. Both window A/C units run as well on R290 as they did on R22. I changed them over for the "because I can" factor, not because they needed it.

I removed the R22 by using a thermal vacuum. I vacced out a propane bottle down to about 200 microns. I then placed it in an esky (cooler, chilly-bin..) packed with dry ice and filled with methylated spirits (denatured alcohol). I did this as the vapor pressure of R22 at ~-70 Degrees C is below atmospheric an therefore it would reliably suck all the R22 out of the system (and I did not own a recovery machine back then).

I then charged the systems up with nitrogen, cut the end of the process tube off and brazed on schraders.

Both systems were charged loosely by monitoring the suction line temp where it leaves the evap (in cooling mode) with my calibrated finger and charging them up until it was "about right". Both systems have done in excess of 18 months service and are going strong. I did not filter or otherwise modify the straight BBQ propane I fed into them.

Since then, I've obtained a couple of proper recovery tank Y-valves and put them in some locally obtained propane tanks. I've also bought a recovery machine and some other assorted fruit to allow me to recirculate propane through a filter and sight glass to clean it up proir to feeding it into my ducted A/C which is sitting in the garage to be installed next weekend.

If you are mixing up gas for your car, you want iso-butane not butane. I went and bought one of every kind of camping gas disposable cylinder I could get my hands on, put them all in the freezer and then measured the pressure at the valve output. Iso-Butane retains higher pressure at 0 Degrees than Butane so it's easy to see which is which.

I then dumped 4 cans into an empty (vacced to 200 microns) propane cylinder and then weighed in the propane on top of that. You need to give the bottle a good shake and roll before you charge it in, and you need to charge it in as a liquid to prevent it fractioning off as it evaporates. I used my gauge set as an expansion valve to dump liquid from the bottle, but charge it into the system as a vapor. The gauges get *really* cold.

There.. now the thread has some real experience.

Hopefully after next weekend, when I hook up my new 7KW ducted system I'll have some more to post.

<edit> Charging scales are REALLY handy. I found some *cheap* shop scales on e-bay that do 30kg with a resolution of 5g. They were about $35 delivered and have a rechargable battery in them. Brilliant for mixing gasses and weighing in and out charges.

Xringer · 01-16-12, 08:07 AM

Welcome Brad, thanks for your post! It's good to see your "real experience" with R290 is getting some good results.

Did you add any lubricant to your converted units? If you did, what did you use?

BradC · 01-16-12, 09:15 AM

No additional lubricant.

When I evacuate systems I do it so slowly that you just don't lose any oil.

One Window A/C is an old reciprocal compressor. It holds over a litre of oil. The other one is a tiny rotary, and it holds a couple of hundred ml's at most. I'd have lost barely a ml of oil out of either system.

My car A/C was an interesting one. I bought the car for $200. It had no gas in the A/C. I vacced it out and it leaked a bit, but I figured I'd get a year out of it before I needed to re-gas it.

It was originally an R12 system, so it had Suniso 5GS mineral oil. Like so many bad retrofits, they just dumped PAG oil on top of that and charged it up with 134a.

When I put the HC's in, it mobilsed *all* the oil, including the stuff that I assume had clogged up the compressor seal. It cools better, pulls down faster and better still, does not leak! I've got a shiny new shaft seal and gasket kit here waiting to rebuild the compressor, and the bugger stopped leaking.

As the leak in the car was a very slow one, there was almost no oil loss out of the seal, so no need to top it up. Now, I need to strip it down and flush it all out as it has too much oil. The bottom 1/3 of the condenser is oil logged and not working at all (I love infra red thermometers!).

You can do as much (or more) damage by over-filling oil as running things dry. You end up with oil logged condensors, or evaps and things get inefficient.

Not so bad with HC refrigerants as they tend to transport most lubricants, but unless you have a leak accompanied by a big oily stain, don't go adding oil.

Now, tonight I've decanted 3KG of propane from a BBQ gas cylinder into one of my dodgy recovery tanks. I used 2 liquid line dessicant driers in series, and the sight glass still indicates the gas is very wet, so I've got to grab another couple of dryers tomorrow and set up my recovery unit to recirculate the gas through the drier cores until it is dry. I've already used an entire 032 core tonight. It's water logged. So it appears propane can be *very* wet out of the bottle.

Probably not so bad from Bernzomatic (or similar) tanks, but this bottle appears to have a *lot* of moisture in it.

Having said that, it's the same source I used to charge up all my other systems (they are all mineral oil though. PAG is very hygroscopic).

It'd be so much easier if the regulatory swines here in Aus actually allowed people to study and test for refrigerant handling licenses. As it is you can't get one unless you do a 4 year apprenticeship (closed and very unionised shop). Not much chance of surviving on apprentice wages at 37 with a family to support. (hrm.. politics bad, mmkay)

Xringer · 01-20-12, 08:23 AM

Quote:

Originally Posted by kbonk

Ha ha, just went to visit these guys,( refrigerantguys.com) they are a US distributor of a Italian company, will be importing new European refrigerants, talked about r 600, maybe r744 too?

I just got some email from these guys.. Their store, is also at this URL,
HVAC and Air Contidioning

Anyways, they sent me a promo code.. It's only for 5%, but better than nothing..

SAVE 5% on your entire order by 02/29/2012

visit HVAC and Air Contidioning and enter the promo code "GREATSAVING" during the checkout.

Min order $75, max discount $50.00, 1 coupon use per customer

Edit:
I just noticed the price of 25 pounds of R410A is a lot cheaper than on Ebay..
http://hvacandairconditioning.com/R4...-P1870646.aspx

BradC · 01-22-12, 08:12 AM

Just an update.

My "processing" setup consists of a home made recovery cylinder (so it has both a vapor and liquid valve), a Sporlan Dry-Eye, a Danfoss sight glass, a Sporlan 162 1/4 Catch all filter-drier and a cheap Chinese recovery machine. This is set up to draw vapor from the tank, the reclaimer compresses and condenses it, it is then throttled with a ball valve to expand into the 2 sight glasses and through the filter before going back into the cylinder liquid port.

I run it for a couple of hours configured like the above, then I reverse it and draw from the liquid line and pump back into the vapor port. The first configuration chills the tank a *lot*, the second warms it quite a bit, but lets the liquid refrigerant linger in the drier for longer.

The liquid line drier works better cold, so I put the ball valve between the recovery machine and the sightglass/filter combo to chill the refrigerant liquid a bit before it passes through.

Thus far it has taken about 8 hours of cycling for the sporlan dry-eye to indicate dry. The Danfoss still says it's wet. I'd love to find a better way to do it though, but you can't buy HC refrigerant here easily yet.

Xringer · 01-22-12, 08:32 AM

Good morning Brad,
It sounds like you have a good rig set up. But 8 hours seems like a long run time.
(Unless you are cleaning up 20 pounds)!!

I have not examined our local BBQ gas yet, but it's likely similar to yours.

I did a quickie filter job on some R410A that I used in a repaired mini-split,
http://ecorenovator.org/forum/geothe...html#post16688
but I was worried about trying to reverse the flow direction, (against the arrow)..
I figured that any debris on the input side of the filter might be back-washed
right back into the system.?.

What do you think? Was I wrong to be worried?

Thanks..

BradC · 01-22-12, 08:51 AM

I've got about 3kg, so about 6.6lb.

Reversing the flow in a filter drier is a sure way of backflushing it. Not a good thing to do if you can avoid it.

AC_Hacker · 01-22-12, 09:12 AM

Quote:

Originally Posted by BradC

...My "processing" setup consists of a home made recovery cylinder (so it has both a vapor and liquid valve), a Sporlan Dry-Eye, a Danfoss sight glass, a Sporlan 162 1/4 Catch all filter-drier and a cheap Chinese recovery machine. This is set up to draw vapor from the tank, the reclaimer compresses and condenses it, it is then throttled with a ball valve to expand into the 2 sight glasses and through the filter before going back into the cylinder liquid port...

Any chance you could take some photos or make a drawing of your setup?

It would sure help folks to construct their own.

Also, are you using this setup to process recovered refrigerants or are you using this setup to "upgrade" non-refrigerant grade HC liquids?

Quote:

Originally Posted by BradC

...you can't buy HC refrigerant here easily yet.

This surprises me. I thought that Australia actually "got it" about the long-term planetary degrading effects of the various proprietary refrigerants?

-AC_Hacker

BradC · 01-22-12, 07:49 PM

Quote:

Originally Posted by AC_Hacker

Any chance you could take some photos or make a drawing of your setup?

It would sure help folks to construct their own.

Also, are you using this setup to process recovered refrigerants or are you using this setup to "upgrade" non-refrigerant grade HC liquids?

Sure, I'll find my camera and take a snap tonight.

I've got some recovered R22 and R134a, but I'm not really using that in anything. R134a is cheaper and easier to get in $15 cans of "freezer spray" from the local electronics store. I use an old R12 can tap I bought on E-bay to pull the refrig direct from the can if I need it. I find it absolutely ironic that it's illegal for me to work on my car A/C if it has 134a in it, yet I can buy it in 250g cans and squirt it straight into the atmosphere!

I'm using this setup to dry out BBQ propane before I use it in my ducted A/C unit. This is the first time I've dried the gas before using it, all the other system I've loaded up just came straight from the bottle. A bit of moisture with mineral oil is not an issue though.

Quote:

Originally Posted by AC_Hacker

This surprises me. I thought that Australia actually "got it" about the long-term planetary degrading effects of the various proprietary refrigerants?

-AC_Hacker

They (we) do, unfortunately the issue is buying any refrigerant without a ticket. None of the big ticket refrig parts stores carries HC refrigerants, and none of the manufacturers really wants to deal with you direct unless you are buying a pallet of the stuff. There is one mob over in Queensland that I might try, but to be honest I had the filter/drier sitting there so it works out cheaper for me just to dry out the BBQ gas.

The thing I'm most interested in is whether I can re-dry the filter-drier after I've used it. Heat and vacuum I believe is the way to do it.

12-29-11, 12:27 PM	#131
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 115 Thanked 250 Times in 230 Posts	Oh, I use all cut and paste.. I normally go to far-out websites like Junk Science.. I liked this one.. The Chevy Volt makes more CO2 using electricity, than using gasoline would.. Detailing the greenwashed Chevy Volt \| JunkScience.com I guess stopping the CO2 from the Keystone XL pipeline (until after the election) will make up for the extra CO2 from all those new Chevy Volt's GM is selling these days.. That was just another joke! The volt isn't really taking off.. But, it costs us a bunch, even if we don't buy one.. "one analyst puts the taxpayer cost at up to $250,000 per each Volt sold" Time to End $7,500 Electric Car Tax Credit \| National Legal and Policy Center It's an insane world we live in today. If I didn't have a sense of humor* about our situation, I would have to disconnect the Fios, halt my news paper delivery and stick my head in the sand.. Or, become a hermit living in the woods, off the grid.. * Humour - Wikipedia, the free encyclopedia "The hypothetical person lacking a sense of humour would likely find the behaviour induced by humour to be inexplicable, strange, or even irrational. " __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

01-15-12, 09:47 PM	#132
BradC Apprentice EcoRenovator Join Date: Dec 2010 Location: Western Australia Posts: 148 Thanks: 1 Thanked 48 Times in 34 Posts	Ok, some practical experience. In Australia we don't have "heat pumps" (we do, but we call them reverse cycle air conditioners). I have 2 Window A/C units (both reverse cycle) and my car A/C running on R290. The car A/C is actually running a 60/40 mix of Propane and Iso-Butane (pressures are close to R12). Both window A/C units are running on straight Propane. I've not taken detailed measurements, therefore my evidence is strictly anecdotal. Both window A/C units run as well on R290 as they did on R22. I changed them over for the "because I can" factor, not because they needed it. I removed the R22 by using a thermal vacuum. I vacced out a propane bottle down to about 200 microns. I then placed it in an esky (cooler, chilly-bin..) packed with dry ice and filled with methylated spirits (denatured alcohol). I did this as the vapor pressure of R22 at ~-70 Degrees C is below atmospheric an therefore it would reliably suck all the R22 out of the system (and I did not own a recovery machine back then). I then charged the systems up with nitrogen, cut the end of the process tube off and brazed on schraders. Both systems were charged loosely by monitoring the suction line temp where it leaves the evap (in cooling mode) with my calibrated finger and charging them up until it was "about right". Both systems have done in excess of 18 months service and are going strong. I did not filter or otherwise modify the straight BBQ propane I fed into them. Since then, I've obtained a couple of proper recovery tank Y-valves and put them in some locally obtained propane tanks. I've also bought a recovery machine and some other assorted fruit to allow me to recirculate propane through a filter and sight glass to clean it up proir to feeding it into my ducted A/C which is sitting in the garage to be installed next weekend. If you are mixing up gas for your car, you want iso-butane not butane. I went and bought one of every kind of camping gas disposable cylinder I could get my hands on, put them all in the freezer and then measured the pressure at the valve output. Iso-Butane retains higher pressure at 0 Degrees than Butane so it's easy to see which is which. I then dumped 4 cans into an empty (vacced to 200 microns) propane cylinder and then weighed in the propane on top of that. You need to give the bottle a good shake and roll before you charge it in, and you need to charge it in as a liquid to prevent it fractioning off as it evaporates. I used my gauge set as an expansion valve to dump liquid from the bottle, but charge it into the system as a vapor. The gauges get really cold. There.. now the thread has some real experience. Hopefully after next weekend, when I hook up my new 7KW ducted system I'll have some more to post. <edit> Charging scales are REALLY handy. I found some cheap shop scales on e-bay that do 30kg with a resolution of 5g. They were about $35 delivered and have a rechargable battery in them. Brilliant for mixing gasses and weighing in and out charges. Last edited by BradC; 01-15-12 at 09:50 PM.. Reason: More info

01-16-12, 08:07 AM	#133
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 115 Thanked 250 Times in 230 Posts	Welcome Brad, thanks for your post! It's good to see your "real experience" with R290 is getting some good results. Did you add any lubricant to your converted units? If you did, what did you use? __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

01-22-12, 08:32 AM	#137
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 115 Thanked 250 Times in 230 Posts	Good morning Brad, It sounds like you have a good rig set up. But 8 hours seems like a long run time. (Unless you are cleaning up 20 pounds)!! I have not examined our local BBQ gas yet, but it's likely similar to yours. I did a quickie filter job on some R410A that I used in a repaired mini-split, http://ecorenovator.org/forum/geothe...html#post16688 but I was worried about trying to reverse the flow direction, (against the arrow).. I figured that any debris on the input side of the filter might be back-washed right back into the system.?. What do you think? Was I wrong to be worried? Thanks.. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less.. Last edited by Xringer; 01-22-12 at 08:34 AM..

01-16-12, 09:15 AM	#134
BradC Apprentice EcoRenovator Join Date: Dec 2010 Location: Western Australia Posts: 148 Thanks: 1 Thanked 48 Times in 34 Posts	No additional lubricant. When I evacuate systems I do it so slowly that you just don't lose any oil. One Window A/C is an old reciprocal compressor. It holds over a litre of oil. The other one is a tiny rotary, and it holds a couple of hundred ml's at most. I'd have lost barely a ml of oil out of either system. My car A/C was an interesting one. I bought the car for $200. It had no gas in the A/C. I vacced it out and it leaked a bit, but I figured I'd get a year out of it before I needed to re-gas it. It was originally an R12 system, so it had Suniso 5GS mineral oil. Like so many bad retrofits, they just dumped PAG oil on top of that and charged it up with 134a. When I put the HC's in, it mobilsed all the oil, including the stuff that I assume had clogged up the compressor seal. It cools better, pulls down faster and better still, does not leak! I've got a shiny new shaft seal and gasket kit here waiting to rebuild the compressor, and the bugger stopped leaking. As the leak in the car was a very slow one, there was almost no oil loss out of the seal, so no need to top it up. Now, I need to strip it down and flush it all out as it has too much oil. The bottom 1/3 of the condenser is oil logged and not working at all (I love infra red thermometers!). You can do as much (or more) damage by over-filling oil as running things dry. You end up with oil logged condensors, or evaps and things get inefficient. Not so bad with HC refrigerants as they tend to transport most lubricants, but unless you have a leak accompanied by a big oily stain, don't go adding oil. Now, tonight I've decanted 3KG of propane from a BBQ gas cylinder into one of my dodgy recovery tanks. I used 2 liquid line dessicant driers in series, and the sight glass still indicates the gas is very wet, so I've got to grab another couple of dryers tomorrow and set up my recovery unit to recirculate the gas through the drier cores until it is dry. I've already used an entire 032 core tonight. It's water logged. So it appears propane can be very wet out of the bottle. Probably not so bad from Bernzomatic (or similar) tanks, but this bottle appears to have a lot of moisture in it. Having said that, it's the same source I used to charge up all my other systems (they are all mineral oil though. PAG is very hygroscopic). It'd be so much easier if the regulatory swines here in Aus actually allowed people to study and test for refrigerant handling licenses. As it is you can't get one unless you do a 4 year apprenticeship (closed and very unionised shop). Not much chance of surviving on apprentice wages at 37 with a family to support. (hrm.. politics bad, mmkay)

01-22-12, 08:12 AM	#136
BradC Apprentice EcoRenovator Join Date: Dec 2010 Location: Western Australia Posts: 148 Thanks: 1 Thanked 48 Times in 34 Posts	Just an update. My "processing" setup consists of a home made recovery cylinder (so it has both a vapor and liquid valve), a Sporlan Dry-Eye, a Danfoss sight glass, a Sporlan 162 1/4 Catch all filter-drier and a cheap Chinese recovery machine. This is set up to draw vapor from the tank, the reclaimer compresses and condenses it, it is then throttled with a ball valve to expand into the 2 sight glasses and through the filter before going back into the cylinder liquid port. I run it for a couple of hours configured like the above, then I reverse it and draw from the liquid line and pump back into the vapor port. The first configuration chills the tank a lot, the second warms it quite a bit, but lets the liquid refrigerant linger in the drier for longer. The liquid line drier works better cold, so I put the ball valve between the recovery machine and the sightglass/filter combo to chill the refrigerant liquid a bit before it passes through. Thus far it has taken about 8 hours of cycling for the sporlan dry-eye to indicate dry. The Danfoss still says it's wet. I'd love to find a better way to do it though, but you can't buy HC refrigerant here easily yet.

01-22-12, 08:51 AM	#138
BradC Apprentice EcoRenovator Join Date: Dec 2010 Location: Western Australia Posts: 148 Thanks: 1 Thanked 48 Times in 34 Posts	I've got about 3kg, so about 6.6lb. Reversing the flow in a filter drier is a sure way of backflushing it. Not a good thing to do if you can avoid it.