Mini Split install - Page 8

brogsie · 11-09-13, 03:50 PM

Xringer,
Is the unit that is mounted low better for heating?
My unit is mounted up high and it seems the floor is always cold.

pinballlooking · 11-09-13, 04:09 PM

The outside unit is installed. Everything is running under and through the deck so it is taking longer.

I did not make a cement pad this time. I just bought two solid blocks from Lowes and put them in the ground 4” leveled them much quicker and only about $3.

Xringer · 11-09-13, 04:22 PM

That was a great place for heating..
http://ecorenovator.org/forum/geothe...ct-2011-a.html

It's blowing right on the middle of the floor of a room, that normally has a VERY cold floor.
Just sitting in there to watch some TV would give you cold feet.
I wanted to install an electrically heated rug to put my feet on!

Now, the floor is much warmer on cold days. It's nice to be able to use our den
during the coldest days of winter.

Anyways, warm air head upwards, so mounting a MS up high is okay for cooling.
But doesn't do real well for heating.
I think the very first MS units were cool only.. Hence the high mount rules in the manuals.

I think the draw back of having it down low, is during cooling.
Air pulled into the intake (on top of the unit) isn't real hot.. (like near the ceiling).
So, if the fan is in Low mode, the air in the room might be warmer than
normal up near the ceiling, and a bit cooler, closer to the floor..
It's not really noticeable that the ceiling is warmer..
Might even be a good thing. Less temperature differential with the hot attic,
likely means less heat conducted down into the living space.

brogsie · 11-09-13, 04:29 PM

Looks like a nice out of the way spot for the compressor pinball.
Is it running yet?

pinballlooking · 11-09-13, 06:31 PM

Quote:

Originally Posted by brogsie

Looks like a nice out of the way spot for the compressor pinball.
Is it running yet?

It is not running yet. I still have more to do. The breaker and 240 wireing still needs done and a handfull more stuff needs done.

Second unit installed. This one did not have the same issues as the other one but had to be mounted a little higher to allow it to drain outside.

brogsie · 11-10-13, 07:54 AM

That one looks like it was a little easier to install.
You were able to get up in the attic behind the unit to run the line sets?

WyrTwister · 11-10-13, 08:23 AM

Quote:

Originally Posted by Xringer

That was a great place for heating..
http://ecorenovator.org/forum/geothe...ct-2011-a.html

It's blowing right on the middle of the floor of a room, that normally has a VERY cold floor.
Just sitting in there to watch some TV would give you cold feet.
I wanted to install an electrically heated rug to put my feet on!

Now, the floor is much warmer on cold days. It's nice to be able to use our den
during the coldest days of winter.

Anyways, warm air head upwards, so mounting a MS up high is okay for cooling.
But doesn't do real well for heating.
I think the very first MS units were cool only.. Hence the high mount rules in the manuals.

I think the draw back of having it down low, is during cooling.
Air pulled into the intake (on top of the unit) isn't real hot.. (like near the ceiling).
So, if the fan is in Low mode, the air in the room might be warmer than
normal up near the ceiling, and a bit cooler, closer to the floor..
It's not really noticeable that the ceiling is warmer..
Might even be a good thing. Less temperature differential with the hot attic,
likely means less heat conducted down into the living space.

I am experimenting with running the ceiling paddle fan on low - medium , in reverse . When running the MS HP .

God bless
Wyr

pinballlooking · 11-10-13, 08:37 AM

I have good attic access and there is a very big laminated beam the whole way across that area.
But I am doing this install by myself I and running the line set from the outside unit under the deck through a hole in the deck up through the soffit by myself was quite the workout it took many trips for this all to work out. Where I put it on the wall was determined by how far the 25’ line set would reach.
I almost made a mistake mounting it to low on the wall. That would have made the water from the unit have to run up hill over a 2 by 6 to run outside. Thankfully is saw that issue and moved the unit up higher on the wall.
I am going to tighten up the line sets, run flexible conduit, pressure test and run the 240v power today. That is the plan anyway.

How long do you need to pressure test for? Last time I did I overnight but how long is long enough?

Xringer · 11-10-13, 09:21 AM

Pressure testing overnight isn't so great, since the cold night will condense the nitrogen
inside the copper and cause the reading to be lower..
So, to be sure.. Wait for the pressure (and temperature) to come back up to what it was when you started.?.

I say keep the pressure test going until the temperature starts changing (a few degrees).
If it's still holding, you could leave it overnight if you wanted to..
But don't be alarmed to see a lower reading in the morning.
Pressure testing is mostly for the flares. Are they tight? Soap them good.

When you start pulling a vacuum, that's when any pin-holes will show up.
Since you won't be able to pull a good vac, if there is even a very tiny leak..

And, there's always that last pressure test. When the R410A is released
into the line set, close the valve one last time and use the liquid soap.
If all is well, tell the R410A certified HVAC guy to release the hounds!!

I ran the Sanyos for about a week and went back an checked the flare fittings one last time.
Might get 1/8 of a turn more.?. Or 1/16th..

NiHaoMike · 11-10-13, 09:36 AM

Quote:

Originally Posted by Xringer

Pressure testing overnight isn't so great, since the cold night will condense the nitrogen
inside the copper and cause the reading to be lower..
So, to be sure.. Wait for the pressure (and temperature) to come back up to what it was when you started.?.

Nitrogen will not condense at those temperatures. It changes pressure due to thermal expansion.

11-09-13, 04:09 PM	#72
pinballlooking Super Moderator Join Date: Jun 2013 Location: SC Posts: 2,923 Thanks: 172 Thanked 564 Times in 463 Posts	The outside unit is installed. Everything is running under and through the deck so it is taking longer. I did not make a cement pad this time. I just bought two solid blocks from Lowes and put them in the ground 4” leveled them much quicker and only about $3. Attached Thumbnails

11-09-13, 04:22 PM	#73
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	That was a great place for heating.. http://ecorenovator.org/forum/geothe...ct-2011-a.html It's blowing right on the middle of the floor of a room, that normally has a VERY cold floor. Just sitting in there to watch some TV would give you cold feet. I wanted to install an electrically heated rug to put my feet on! Now, the floor is much warmer on cold days. It's nice to be able to use our den during the coldest days of winter. Anyways, warm air head upwards, so mounting a MS up high is okay for cooling. But doesn't do real well for heating. I think the very first MS units were cool only.. Hence the high mount rules in the manuals. I think the draw back of having it down low, is during cooling. Air pulled into the intake (on top of the unit) isn't real hot.. (like near the ceiling). So, if the fan is in Low mode, the air in the room might be warmer than normal up near the ceiling, and a bit cooler, closer to the floor.. It's not really noticeable that the ceiling is warmer.. Might even be a good thing. Less temperature differential with the hot attic, likely means less heat conducted down into the living space. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

11-10-13, 09:21 AM	#79
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	Pressure testing overnight isn't so great, since the cold night will condense the nitrogen inside the copper and cause the reading to be lower.. So, to be sure.. Wait for the pressure (and temperature) to come back up to what it was when you started.?. I say keep the pressure test going until the temperature starts changing (a few degrees). If it's still holding, you could leave it overnight if you wanted to.. But don't be alarmed to see a lower reading in the morning. Pressure testing is mostly for the flares. Are they tight? Soap them good. When you start pulling a vacuum, that's when any pin-holes will show up. Since you won't be able to pull a good vac, if there is even a very tiny leak.. And, there's always that last pressure test. When the R410A is released into the line set, close the valve one last time and use the liquid soap. If all is well, tell the R410A certified HVAC guy to release the hounds!! I ran the Sanyos for about a week and went back an checked the flare fittings one last time. Might get 1/8 of a turn more.?. Or 1/16th.. __________________ My hobby is installing & trying to repair mini-splits EPA 608 Type 1 Technician Certification ~ 5 lbs or less..

11-09-13, 03:50 PM	#71
brogsie Helper EcoRenovator Join Date: Oct 2013 Location: mass Posts: 51 Thanks: 26 Thanked 3 Times in 2 Posts	Xringer, Is the unit that is mounted low better for heating? My unit is mounted up high and it seems the floor is always cold.

11-09-13, 04:29 PM	#74
brogsie Helper EcoRenovator Join Date: Oct 2013 Location: mass Posts: 51 Thanks: 26 Thanked 3 Times in 2 Posts	Looks like a nice out of the way spot for the compressor pinball. Is it running yet?

11-10-13, 07:54 AM	#76
brogsie Helper EcoRenovator Join Date: Oct 2013 Location: mass Posts: 51 Thanks: 26 Thanked 3 Times in 2 Posts	That one looks like it was a little easier to install. You were able to get up in the attic behind the unit to run the line sets?

11-10-13, 08:37 AM	#78
pinballlooking Super Moderator Join Date: Jun 2013 Location: SC Posts: 2,923 Thanks: 172 Thanked 564 Times in 463 Posts	I have good attic access and there is a very big laminated beam the whole way across that area. But I am doing this install by myself I and running the line set from the outside unit under the deck through a hole in the deck up through the soffit by myself was quite the workout it took many trips for this all to work out. Where I put it on the wall was determined by how far the 25’ line set would reach. I almost made a mistake mounting it to low on the wall. That would have made the water from the unit have to run up hill over a 2 by 6 to run outside. Thankfully is saw that issue and moved the unit up higher on the wall. I am going to tighten up the line sets, run flexible conduit, pressure test and run the 240v power today. That is the plan anyway. How long do you need to pressure test for? Last time I did I overnight but how long is long enough?