Heat Wave 2022

Poppy

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Joined
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Location
Northern New Jersey
The AC in this house struggles when the outside temps reach 88F.

My windows crank out, and the opening is too small to put my 10,000 BTU unit in it. So I devised a way to lie it on the floor of the family room, through the sliding door, and fill the top with a hard sheet of polyvinyl foam. It works well, but the house is not secure when it is there so I have to take it out when we leave, and only put it back in when needed.

1658515878717.png



This past week it has been needed every day. A real PIA. SO I ordered a 14,000 btu dual hose portable, and installed it yesterday morning.

1658514568237.png


Despite it being 93F it is blowing 53 F air.

It is a 110V unit and can be powered by my generator if there is a power outage.

A couple of weeks ago, I set the thermostat of my attic fan properly, so that is now working nicely. One can really feel the heat being evacuated from the attic if one stands near the exhaust.

I was a bit dismayed, the the house couldn't maintain 72F even with the addition of the portable unit. The indoor temp creeped up to 77F. I used a instant read digital thermometer (that I cook with) to read the temp coming out of the central AC vents. 80F !

I went outside, and the condenser coil fan was blowing, but the compressor wasn't on. I looked all around the condenser coil and the side that one can see from the yard was nice and clean. However, the side facing the house, and one end, was so dirty and matted, that NO air could have been getting through. I took the garden hose to it, and the compressor kicked back on. It must have turned off due to excessive heat, or pressure.

At any rate, the temps coming out of the vents are now in the mid to high fifties. :)

I suggest that you change your filter if you haven't recently, and clean your condenser coil. If you can get to your evaporator coil, that may benefit from a cleaning too.
 
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I looked at the filter in my son's house recently because it was making a sucking sound where the air goes into the system. He uses 90 day filters, which in my view are 30 day filters. He replaced it and the sucking sound changed to a humming sound coming from all the air (now) getting through the slots in the grate(s) and within two days he said "dad my house is more comfy and the ac does not run as much." I replied "change your filter on the first of the month every month and you won't regret it". The filters he uses are about $6 each but having a clogged one probably adds $20 a month to his power bill.

And I've also cautioned him not to spray grass clippings on the coils when cutting grass. That can really matter too.
 
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The AC in this house struggles when the outside temps reach 88F.

My windows crank out, and the opening is too small to put my 10,000 BTU unit in it. So I devised a way to lie it on the floor of the family room, through the sliding door, and fill the top with a hard sheet of polyvinyl foam. It works well, but the house is not secure when it is there so I have to take it out when we leave, and only put it back in when needed.

View attachment 30034


This past week it has been needed every day. A real PIA. SO I ordered a 14,000 btu dual hose portable, and installed it yesterday morning.

View attachment 30033

Despite it being 93F it is blowing 53 F air.

It is a 110V unit and can be powered by my generator if there is a power outage.

A couple of weeks ago, I set the thermostat of my attic fan properly, so that is now working nicely. One can really feel the heat being evacuated from the attic if one stands near the exhaust.

I was a bit dismayed, the the house couldn't maintain 72F even with the addition of the portable unit. The indoor temp creeped up to 77F. I used a instant read digital thermometer (that I cook with) to read the temp coming out of the central AC vents. 80F !

I went outside, and the condenser coil fan was blowing, but the compressor wasn't on. I looked all around the condenser coil and the side that one can see from the yard was nice and clean. However, the side facing the house, and one end, was so dirty and matted, that NO air could have been getting through. I took the garden hose to it, and the compressor kicked back on. It must have turned off due to excessive heat, or pressure.

At any rate, the temps coming out of the vents are now in the mid to high fifties. :)

I suggest that you change your filter if you haven't recently, and clean your condenser coil. If you can get to your evaporator coil, that may benefit from a cleaning too.

you are leaking heat back into the house with that portable unit, you might want to insulate the exhaust pipe like so

1658521973137.png


we had to use a mobile unit when we lived there and it made a world of difference that the exhaust was insulated. I'm not sure if I still have my thermal pictures of the before after, but it definitely makes a difference that you don't allow the heat to be introduced back into the room via the piping
 
July has been unpleasant in the DFW area. In keeping with the state's power woes I cool down to 70F midnight until 06:00, hold 72F until 14:00, set an 'ERCOT' period holding 76F from 14:00 - 20:00, then bump down to 72F until midnight.

I conceded to reality in the office last year:
1658523803841.png


The windows are end of life and I just don't want to pay several thousand dollars to replace them so instead I've got two layers of 1" R4 polystyrene insulation which make a considerable difference.

I've not much run the portable AC this year since making the 'ERCOT' thermostat settings - the present central AC settings are generally keeping the office at <80F which I find comfortable enough. The additional load the portable puts on the central AC is a bit of a paradox - it seems to inflict additional net heat load before it starts making a dent. I'm well aware of the downsides of single-hose units, however this was a cheap secondhand unit after its dual-hose predecessor expired. I do wish the market would devise a low-profile zero-projection window unit - or just a quieter dual-hose portable unit - since I expect that additional supplementary cooling will be necessary in the future ... or I can cough up for a supplementary multizone ductless system to serve the upstairs rooms.

This weekend I'll attempt to source a patio umbrella for the central AC compressor - I gather that in this kind of heat reducing solar load can make an appreciable difference.
 
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I have sloped windows in my bedroom so I also unfortunately have to rely on one of these portable AC units. I must use 3 separate pieces of cut-to-shape styrofoam to cover the opening in my window & then cover the gaps with duct tape to prevent the warm air from rushing inside. I then insulate the hose by warping it with 4 towels. Setting this up takes at least 10-15 minutes every time. Portable units ere very inefficient & leak a lot of heat back into the room. Double hose units are better but still not great. Window units are great but they dont work with our german windows, which tilt instead of slide.

Its all a PITA to say the least.
 
I do wish the market would devise a low-profile zero-projection window unit - or just a quieter dual-hose portable unit - since I expect that additional supplementary cooling will be necessary in the future ... or I can cough up for a supplementary multizone ductless system to serve the upstairs rooms.

The new mini-split systems are very efficient.

I always thought that 220V systems were more efficient than 110V systems, but after doing some reading, it appears that they are not, or at least not appreciably so. Therefore I would go with a 110 unit so that it could be powered by my/your 110v inverter generator set up if necessary.
 
you are leaking heat back into the house with that portable unit, you might want to insulate the exhaust pipe like so

View attachment 30037

we had to use a mobile unit when we lived there and it made a world of difference that the exhaust was insulated. I'm not sure if I still have my thermal pictures of the before after, but it definitely makes a difference that you don't allow the heat to be introduced back into the room via the piping
My hose run is quite short, but it is warm, and does put some btu's back into the house, no doubt. Actually I have to close up some air leaks between the pieces of foam I used to close up the window. I'm not sure if I am going to leave it there or move it one window to the left. Functionally it won't make a difference, but perhaps aesthetically.

Since my windows swing out, I can turn the AC off when I leave, and close the window, and it is as secure as it normally would be. Otherwise, it would be a simple matter to push through the foam pieces for forced entry.

I would strongly suggest that anyone considering getting a portable unit, be sure to get a dual hose one. Or one that has a hose within a hose. The single hose units are terribly inefficient! All while they are running, they are pumping air out of the hose creating a virtual vacuum inside. Therefore outside humid air will find its way back into the house through any little crack or crevice, or when the door is opened and closed. Also a single hose unit uses air from inside the house that you already paid to cool, to cool off the condenser coil, and expel it outside. IMO... NOT a good idea!
 
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My hose run is quite short, but it is warm, and does put some btu's back into the house, no doubt. Actually I have to close up some air leaks between the pieces of foam I used to close up the window. I'm not sure if I am going to leave it there or move it one window to the left. Functionally it won't make a difference, but perhaps aesthetically.

Since my windows swing out, I can turn the AC off when I leave, and close the window, and it is as secure as it normally would be. Otherwise, it would be a simple matter to push through the foam pieces for forced entry.

I would strongly suggest that anyone considering getting a portable unit, be sure to get a dual hose one. Or one that has a hose within a hose. The single hose units are terribly inefficient! All while they are running, they are pumping air out of the hose creating a virtual vacuum inside. Therefore outside humid air will find its way back into the house through any little crack or crevice, or when the door is opened and closed. Also a single hose unit uses air from inside the house that you already paid to cool to cool off the condenser coil, and expel it outside. IMO... NOT a good idea!

portable units are generally a very bad idea, it should be the last thing to consider. a good portable costs exactly as much as a split one ( or at least here it is the same ) and it has a myriad of issues we discussed here...

for some scenarios you have to go portable, but people generally don't take into account the numerous additional things you need to do, like doing the heat insulation yourself, dealing with the airflow and air leaks and so on
 
Who has a line on a reliable, effective mini split?

Yesterday our 15 year old whole house inverter (output max 29Amps 110VAC) was not functioning when we got home in the afternoon. Seems we had a rainstorm with electrical complication while we were gone (neighbors corroborated) as 2 breakers labeled array (as in solar) tripped. After hours of trying this and trying that, no go.

I installed an exhaust fan in the loft last summer and will use a portable 600W inverter to energize that tonight to draw in cool night air (inverter is connected via heavy duty jumper cables to two 6V golf cart sized AGM batteries within the string of 4S 3P powering our system), but no ceiling fan is a bummer during the day. Rarely have we reached 90+ degrees in the past; now all too often. Hence the question of mini split sourcing. We have a very small house.
 
In my last two houses, my AC units were also old, and the compressor wouldn't kick on. The issue was the "start capacitor" swapping it out for about $15 was easier than baking apple pie. I found out, how to check them with a multi-meter, on youtube.

At the last house, it happened pretty much each time there was a lightening strike anywhere nearby. I had a PSE&G contract, and the service man said that it is a common occurrence. He or others had been to the house a few times.
 
We've been lucky, so far; we haven't lost power. I guess that NJ power companies have enough reserve capacity, that when given enough notice, they can crank up their output to meet the anticipated needs/demands.

It's predicted that we will have actual temps in the mid to high 90's today and tomorrow, with lows in the high 70's, with high humidity, bringing the heat index (feels like) temps to around 100-105 F.
 
We've been lucky, so far; we haven't lost power. I guess that NJ power companies have enough reserve capacity, that when given enough notice, they can crank up their output to meet the anticipated needs/demands.
That and you live within the Eastern Interconnection and can call upon generating capacity some ways away if necessary.
 
In our last home, not too long before selling, we installed central A/C. Prior to that we were using a med/large window unit with pretty good results. Without checking into getting central air internet searches into estimates gave prices in the $4-7,000. This being more than we felt needed since the window unit wasn't bad. When we decided to sell we did some significant improvements including redoing all the decks, new windows, hickory on the entire first level, custom hickory cabinets, premium granite, and new carpet through out. The extent of our improvements put our home into a category where it would seem out derogatory to not have central air. When I called and the guy came out and gave his estimate I was astounded. The local dealer sold Lennox units and the installed price was only $2600. I think we may have paid a bit less because they didn't have to run 220 because we already had a circuit from where there used to be a hot tub and cash discount. But had I gotten an estimate years ago I wouldn't have been lifting and storing that big window AC for so many years.
 
Temperature due to be 107 degrees here on Saturday, we have plumbed in air con units for each of the bed rooms and the living room, the solar panels will be doing their bit to keep us at a decent temperature over the weekend.
 
Remove a few light switch and outlet covers. If they are packed with dust, you have HVAC air leak(s) in the ductwork. You lose air on the supply/duct side. This creates a vacuum inside the house.

Air/Dust infiltrates however it can... usually through the attic, top plate, down the wall, and through the electrical switches/outlets.

And yes, compressor coils need cleaning periodically. I placed my units on concrete blocks I formed/poured that are about 12-16" tall. This goes a LONG way toward having 1) clean coils from dust 2) clean coils from mowing debris 3) damaged coils from mowing/trimming/etc. Also, your HVAC guy will love you as they don't have to work at ground level.

And what's the deal with 72F??? I'm not cold natured but could not imagine a house that cold. I'm set at 75 24x7x365 and am considering moving to 76.

My temps are accurate... they are not skewed by a thermostat in sunlight or near heat/cold sources. 72... that would be cold enough to hang meat.
 
I really hate sharing my money with power company. Thermostats in my home are set at 82F. Auto's I leave it around 78.. Too much shock on human body when stepping out to over 100F
 
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