Minisplit install lessons learned

BMR · 09-05-13, 04:12 PM

I recently completed a self-install of an LG mini split heat pump and thought I would share some of my lessons learned as a way of making some small contribution in return for the debt of gratitude I owe to these forums. I can’t tell you how much the prior posts here helped me in this project.
I’m not going to do a step by step install as others have already done such a great job with them. Instead I thought I’d list a few of the things I stumbled through that might help others in the future.

1. Read the posts here that are a great guide. I feel I especially owe Xringer and ACHacker a big thank you.

2. Practice with the tools. The most difficult thing for me was getting used to the fittings on the manifold hoses. They needed to be less tight than I expected. Some of them were very touchy about being tight enough to not leak, but if I made them too tight they seemed to be not open to a vacuum. I assume this was due to whatever refrigerant retention valve that was in them. I would also recommend practicing with the entire vacuum setup before you do the final flare connections. If you do that and can hear air rushing in through the flare connectors, you know for sure that you have a good connection through all of your hoses and the service valve and will be pulling a vacuum on the whole system, not just your gauge and hoses.

3. I recommend leak testing. I have welding shielding gas around, so the only additional expense was $50 for a regulator. When you leak test, be sure to disconnect your hoses from the service valve after you’ve pressurized everything. Otherwise you are not testing it. In my case I really had to tighten my 5/16 adapter in order to get it to stop leaking. I later learned that this had pushed the Schrader valve too far in, causing it to jam. When I removed the adapter and hoses, all of the leak test gas came rushing out. I sure was glad that wasn’t the R410A. It appears that I had a defective adapter – see below on equipment quality. I suppose it’s also possible the Schrader valve wasn’t fully installed at the factory, but that seems much less likely.

4. Don’t overtighten the flare fittings. The LG manual had a surprisingly large range for tightening torque on the smaller fitting. I went on the high side of this, using a torque wrench, which was a mistake. I later attempted to move the lineset a little and it snapped at the flare. All before I had released the refrigerant, thankfully. I looked at other manufacturer manuals and they don’t have such high torques. I think it may be an error in the LG manual. The lesson for me was to aim for the middle of the torque range and also listen to your arm when it is telling you that you’re going too tight. Also do all of the bending of the lineset prior to connecting the flares.

5. Put some nylog (or refrigerant oil) on the back of the flares as well. When I was tightening the flares, the tubing was trying to spin. This probably contributed to my flare failure above. Once I put nylog on the back this stopped.

6. Buy decent tools. For most of the things I needed, a low-end USA-made professional tool was only marginally more expensive than an “occasional use” tool. The exceptions were the two-stage vacuum pump, which I got from harbor freight because it looked identical to others out there, and my first 5/16 adapter, which was a lesson learned the hard way. I did splurge on a yellow jacket flaring tool since at that point I was willing to pay for whatever would allow me to finish up the project with the fewest number of headaches.

7. NAPA carries a surprising amount of AC equipment. You can get vacuum oil there without having to pay the high shipping costs of online sellers. They also have things like valve cores available when you really need them. No R410A-specific equipment, obviously.

8. Wire ties that have a hole for screws worked really well for securing the lineset to the side of the house. PEX Supply was the only place I could find selling lineset tape, and it was reasonably priced when I was able to share the shipping cost with some plumbing supplies I needed for another project.

It’s very satisfying to have this up and running, and I am very pleased with the unit. I will say that at the time I did not enjoy this as much as other DIY projects (both home and auto) that I have done. I think I was overly concerned with ruining a $1000+ unit, or more likely, the potential embarrassment of having to call in a pro to complete the job if I failed at some point.

Thanks again to all on here that have posted on this in the past, and I hope that listing my mistakes here will help someone else avoid them in the future.

jeff5may · 09-06-13, 06:39 AM

Welcome to the forums! I have learned way too much to describe here also. This forum and its members are hands-on and helpful, two qualities that are hard to come by in this day and age.

WyrTwister · 09-28-13, 09:45 AM

Quote:

Originally Posted by jeff5may

Welcome to the forums! I have learned way too much to describe here also. This forum and its members are hands-on and helpful, two qualities that are hard to come by in this day and age.

I agree 100% . This forum really helped me . Even with that , I made my share of mistakes . :-(

I have really enjoyed my mini-split , this summer . As the weather begins to cool , I will have my first experience with a heat pump . I will be experimenting with it .

God bless
Wyr

Daox · 09-28-13, 12:01 PM

Keep us updated Wyr! You guys feedback and contributions make this site what it is.

WyrTwister · 09-28-13, 12:28 PM

Quote:

Originally Posted by Daox

Keep us updated Wyr! You guys feedback and contributions make this site what it is.

I may try to mostly try to use the mini split HP as my main heat source , in the early fall . At least until I see what the electric bill and natural gas bill look like .

Our central unit is an older R22 A/C & 92% gas fired furnace . I suspect I will need to fire it up , when the colder winter months arrive ?

Did I mention , I love the quite of the mini split , especially when I am watching TV ? :-)

Thanks again for the help and encouragement ! :-)

God bless
Wyr

BMR · 09-30-13, 03:43 PM

I finally got to try out my new unit in heating mode a few days ago and am happy to report that it worked great. I'm looking forward to see how it will perform in much colder weather.

My only complaint with the LG unit is that it does not seem to have an auto fan setting while in a specific (heating, cooling, dehumidification) mode. It will do it when in the fully auto (AI) mode, but since my set points for heating and cooling are about 10 degrees apart, I have little use for a mode that will automatically switch between them.

Xringer · 09-30-13, 07:41 PM

Even before the leafs started tumbling down, we had the old Sanyos on heat mode a few times lately.
I've heard this winter is gonna be a cold one! I hope the forecasters are wrong..
Already seeing a few oil trucks on the street..

Nice to see folks are reading my old posts. Avoiding a few mistakes that I made.

Never used the Auto heat/cool mode but once. It really didn't impress me.
Once it gets colder, you might be able to use AI since it will be forced (by weather) to stay in heat mode.
I like full auto fan mode, because it stays at low speed 90% of the time.
But, when it needs to move some heat, it jumps up the RPMs.

If you can stay up late, you will be sitting around watching your LG
whenever the temps get down under 10deg F..
It's fascinating to feel the heat that was just pulled out of 6F outdoor air..
(At least to me, being easy to entertain)..

WyrTwister · 10-01-13, 08:00 AM

Quote:

Originally Posted by BMR

I finally got to try out my new unit in heating mode a few days ago and am happy to report that it worked great. I'm looking forward to see how it will perform in much colder weather.

My only complaint with the LG unit is that it does not seem to have an auto fan setting while in a specific (heating, cooling, dehumidification) mode. It will do it when in the fully auto (AI) mode, but since my set points for heating and cooling are about 10 degrees apart, I have little use for a mode that will automatically switch between them.

My unit appears to have an auto fan mode in cool . Really have not used heat mode , only played witg it a very little .

God bless
Wyr

AC_Hacker · 10-01-13, 09:49 AM

Quote:

Originally Posted by BMR

I recently completed a self-install of an LG mini split heat pump and thought I would share some of my lessons learned...

Congratulations on your successful install! It's really like jumping into the deep end of the pool, isn't it.

Glad the info on the forum was useful.

So, the big question is... now that your confidence level is in full turbo mode, what's your next project?

Best,

-AC

WyrTwister · 10-01-13, 01:10 PM

Quote:

Originally Posted by AC_Hacker

Congratulations on your successful install! It's really like jumping into the deep end of the pool, isn't it.

Glad the info on the forum was useful.

So, the big question is... now that your confidence level is in full turbo mode, what's your next project?

Best,

-AC

My next project needs to be replace & upgrade my electrical service . Now that it is cooling off . Main hold up is getting off my lazy behind and doing it . :-(

God bless
Wyr

09-05-13, 04:12 PM	#1
BMR Lurking Renovator Join Date: Sep 2013 Location: MA Posts: 9 Thanks: 0 Thanked 5 Times in 2 Posts	Minisplit install lessons learned I recently completed a self-install of an LG mini split heat pump and thought I would share some of my lessons learned as a way of making some small contribution in return for the debt of gratitude I owe to these forums. I can’t tell you how much the prior posts here helped me in this project. I’m not going to do a step by step install as others have already done such a great job with them. Instead I thought I’d list a few of the things I stumbled through that might help others in the future. 1. Read the posts here that are a great guide. I feel I especially owe Xringer and ACHacker a big thank you. 2. Practice with the tools. The most difficult thing for me was getting used to the fittings on the manifold hoses. They needed to be less tight than I expected. Some of them were very touchy about being tight enough to not leak, but if I made them too tight they seemed to be not open to a vacuum. I assume this was due to whatever refrigerant retention valve that was in them. I would also recommend practicing with the entire vacuum setup before you do the final flare connections. If you do that and can hear air rushing in through the flare connectors, you know for sure that you have a good connection through all of your hoses and the service valve and will be pulling a vacuum on the whole system, not just your gauge and hoses. 3. I recommend leak testing. I have welding shielding gas around, so the only additional expense was $50 for a regulator. When you leak test, be sure to disconnect your hoses from the service valve after you’ve pressurized everything. Otherwise you are not testing it. In my case I really had to tighten my 5/16 adapter in order to get it to stop leaking. I later learned that this had pushed the Schrader valve too far in, causing it to jam. When I removed the adapter and hoses, all of the leak test gas came rushing out. I sure was glad that wasn’t the R410A. It appears that I had a defective adapter – see below on equipment quality. I suppose it’s also possible the Schrader valve wasn’t fully installed at the factory, but that seems much less likely. 4. Don’t overtighten the flare fittings. The LG manual had a surprisingly large range for tightening torque on the smaller fitting. I went on the high side of this, using a torque wrench, which was a mistake. I later attempted to move the lineset a little and it snapped at the flare. All before I had released the refrigerant, thankfully. I looked at other manufacturer manuals and they don’t have such high torques. I think it may be an error in the LG manual. The lesson for me was to aim for the middle of the torque range and also listen to your arm when it is telling you that you’re going too tight. Also do all of the bending of the lineset prior to connecting the flares. 5. Put some nylog (or refrigerant oil) on the back of the flares as well. When I was tightening the flares, the tubing was trying to spin. This probably contributed to my flare failure above. Once I put nylog on the back this stopped. 6. Buy decent tools. For most of the things I needed, a low-end USA-made professional tool was only marginally more expensive than an “occasional use” tool. The exceptions were the two-stage vacuum pump, which I got from harbor freight because it looked identical to others out there, and my first 5/16 adapter, which was a lesson learned the hard way. I did splurge on a yellow jacket flaring tool since at that point I was willing to pay for whatever would allow me to finish up the project with the fewest number of headaches. 7. NAPA carries a surprising amount of AC equipment. You can get vacuum oil there without having to pay the high shipping costs of online sellers. They also have things like valve cores available when you really need them. No R410A-specific equipment, obviously. 8. Wire ties that have a hole for screws worked really well for securing the lineset to the side of the house. PEX Supply was the only place I could find selling lineset tape, and it was reasonably priced when I was able to share the shipping cost with some plumbing supplies I needed for another project. It’s very satisfying to have this up and running, and I am very pleased with the unit. I will say that at the time I did not enjoy this as much as other DIY projects (both home and auto) that I have done. I think I was overly concerned with ruining a $1000+ unit, or more likely, the potential embarrassment of having to call in a pro to complete the job if I failed at some point. Thanks again to all on here that have posted on this in the past, and I hope that listing my mistakes here will help someone else avoid them in the future. Last edited by BMR; 09-05-13 at 05:57 PM..

09-28-13, 12:01 PM	#4
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Keep us updated Wyr! You guys feedback and contributions make this site what it is. __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

09-30-13, 07:41 PM	#7
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Even before the leafs started tumbling down, we had the old Sanyos on heat mode a few times lately. I've heard this winter is gonna be a cold one! I hope the forecasters are wrong.. Already seeing a few oil trucks on the street.. Nice to see folks are reading my old posts. Avoiding a few mistakes that I made. Never used the Auto heat/cool mode but once. It really didn't impress me. Once it gets colder, you might be able to use AI since it will be forced (by weather) to stay in heat mode. I like full auto fan mode, because it stays at low speed 90% of the time. But, when it needs to move some heat, it jumps up the RPMs. If you can stay up late, you will be sitting around watching your LG whenever the temps get down under 10deg F.. It's fascinating to feel the heat that was just pulled out of 6F outdoor air.. (At least to me, being easy to entertain).. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

09-06-13, 06:39 AM	#2
jeff5may Supreme EcoRenovator Join Date: Jan 2010 Location: elizabethtown, ky, USA Posts: 2,428 Thanks: 431 Thanked 619 Times in 517 Posts	Welcome to the forums! I have learned way too much to describe here also. This forum and its members are hands-on and helpful, two qualities that are hard to come by in this day and age.

09-30-13, 03:43 PM	#6
BMR Lurking Renovator Join Date: Sep 2013 Location: MA Posts: 9 Thanks: 0 Thanked 5 Times in 2 Posts	I finally got to try out my new unit in heating mode a few days ago and am happy to report that it worked great. I'm looking forward to see how it will perform in much colder weather. My only complaint with the LG unit is that it does not seem to have an auto fan setting while in a specific (heating, cooling, dehumidification) mode. It will do it when in the fully auto (AI) mode, but since my set points for heating and cooling are about 10 degrees apart, I have little use for a mode that will automatically switch between them.