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Replace Penguin Heat Pump: what's involved?


wamcneil

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16 minutes ago, Ray Davis said:

Walter ,  Your roof opening is not quite the same as mine at least the duct is different .  If the duct does not compress farther I don't see that as

causing a perceptible restriction .  Guess you'll have to figure that part out .

Never the less we are using the same Penguin A/C and drain set up so more than likely the gasket install will be the same .

What I meant by additional gasket is my drain kit came with only one thicker gasket but my old A/C used two .

Image result for Drain Kit for Dometic Air Cond

This kit plus another gasket without the drain pans etc .   Perhaps the drain tubes can be made to work with one gasket but two gaskets were

shown in my A/C installation instructions .

Have you flipped the old unit over to see how yours is put together ?

BTW my instructions mention torque but it also say compress the gasket 1/2 inch .  Guess they realize most don't have an in lb torque wrench .

 

now WHERE is that 500 Thousandths Feeler Gage that I KNOW I had???

Thanks for the insight.  You guys are gonna convince me to do the two AC upgrade myself.  However the attorney's fees for my divorce would far exceed the savings in labor and I would really miss the DW....LOL

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Thanks Ray

I'm still not following on the gasket though.
The drain pan drain instructions I found online make it sound like one square gasket is already installed on the A/C pan. I’m supposed to make two cutouts in this gasket for the drain tubes. Then install the tubes and fill in around the tubes with sealant.  See attachment.
Then there’s a 2nd square gasket in the drain kit that is installed over the first gasket. That's the way the old unit is: two gaskets on top of each other. The upper gasket is cut to pass the drain tubes. And there are two straight sections of gasket stacked at the rear of the base pan.
Are you saying the A/C doesn’t come with the square gasket pre-installed?

Or are you saying that your old unit had THREE stacked gaskets?

Or are you talking about the straight sections of gasket at the rear of the A/C pan?

Thanks

Walter

gasket.jpg

Edited by wamcneil
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Guest Ray Davis

 3 gaskets were never mentioned only 2 

 Mine did not come with a gasket yours may .

 Again did you flip the unit so you can see ?

 Flip it and post a picture 

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Here's what my old one looks like. 

So you're saying the new penguin II did NOT come with the base gasket preinstalled? The installation instructions for the A/C and the drain kit both mention it like it's already installed on the pan.

Maybe I need to call Dometic and see if it should come with the base gasket.

Walter

gaskets2.jpg

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  • 4 weeks later...

Hi everybody. Just a followup to this post.

The new unit has been installed and running for a couple weeks now. Just a few cosmetic details to complete, like making a plug to fill a big hole where I moved the kitchen fan thermostat over to make room for the CCC2.

Installation was pretty straightforward, but here are some notes on my experience.

Removal: The old square gasket gets fused to the roof like you wouldn't believe. I mean like 3M 5200 fused to a boat deck. If I were doing it again I'd cut some wedges out of 2x4 scrap to keep upward pressure on the seal, then get in there with a long knife and water lubricant to cut through the middle of the gasket rather than try and get a putty knife under the gasket. Once the unit has been lifted off, it's pretty straightforward to scrape the gasket off with a sharp putty knife and then clean up with solvent. 

Duct was deformed: The old unit had apparently been retightened over the years, to the point where the drain cups were touching the roof. This caused the ceiling duct to be forced down >1/2". It didn't rebound on its own, so I cut a wood spacer to go between the roof structure and the rear of the transition stub, and screwed the sheetmetal transition duct back into the wood to hold it up and level. In its final position, the AC's bottom pan is less than 1/4" above the duct extension, so there's not much room to further tighten the bolts. Not without shortening the transition duct.

Bolt tightness: The regular instructions say to tighten bolts to 40-50 in-lb.  I didn't get the bolts anywhere near that tight before the two stacked gaskets had compressed 1/2". So I stopped there. I also ignored the drain pan instructions where they say to put a double-stacked strips of gasket at the back of the unit (which would hold the unit up off the normal 3/4" hard-foam pads and support the back of the pan). So I doubled up the hard-foam pads at the back to make them 1-1/2" thick and tightened the bolts till the 2" thick stacked square gaskets had compressed to 1-1/2". This left the bolts way looser than 40 in-lb. But if I go anywhere near that toque spec it'll pull the unit right down on the deck. I think I'll make some marks on the roof with sharpie so I can tell if is the units moves at all in transit and go from there.

Electrical: New units come with a mobile-home electrical connector pre-installed on the power cable. At least mine did... but Dometic only gave me 1 half of the connector pair. The connector is thin/flat and certified as a junction box. This opens up some additional room for airflow around the side of the duct (vs- the old steel junction box), so I bought the other half of the connector pair and used it. There are many variations of this Self-Contained Power Connector (SCPC), and here is the specific part if you need the other half for 12ga romex:

https://www.mouser.com/ProductDetail/molex/19045-1000/?qs=c7V%2bsbZfmqvqLYL%2bCrIKLw%3D%3D&countrycode=US&currencycode=USD

Noise: I was really hoping to wind up with a quieter unit. It is not, unfortunately 😒. In fact my iphone dB meter says it's about 2dB louder than my old center unit. Almost all of the noise is from the fan though. Pretty much can't hear the compressor at all. So, I'm going to experiment with some blocks of acoustic foam on the duct sides directly beneath the evaporator intake and see if I can trap some of the fan noise rather than let it come straight down through the filter. Initial experiments with wadded up kitchen towels were encouraging.

Cheers,

Walter

 

Edited by wamcneil
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On 9/17/2020 at 2:02 PM, wamcneil said:

Hi everybody. Just a followup to this post.

The new unit has been installed and running for a couple weeks now. Just a few cosmetic details to complete, like making a plug to fill a big hole where I moved the kitchen fan thermostat over to make room for the CCC2.

Installation was pretty straightforward, but here are some notes on my experience.

Removal: The old square gasket gets fused to the roof like you wouldn't believe. I mean like 3M 5200 fused to a boat deck. If I were doing it again I'd cut some wedges out of 2x4 scrap to keep upward pressure on the seal, then get in there with a long knife and water lubricant to cut through the middle of the gasket rather than try and get a putty knife under the gasket. Once the unit has been lifted off, it's pretty straightforward to scrape the gasket off with a sharp putty knife and then clean up with solvent. 

Duct was deformed: The old unit had apparently been retightened over the years, to the point where the drain cups were touching the roof. This caused the ceiling duct to be forced down >1/2". It didn't rebound on its own, so I cut a wood spacer to go between the roof structure and the rear of the transition stub, and screwed the sheetmetal transition duct back into the wood to hold it up and level. In its final position, the AC's bottom pan is less than 1/4" above the duct extension, so there's not much room to further tighten the bolts. Not without shortening the transition duct.

Bolt tightness: The regular instructions say to tighten bolts to 40-50 in-lb.  I didn't get the bolts anywhere near that tight before the two stacked gaskets had compressed 1/2". So I stopped there. I also ignored the drain pan instructions where they say to put a double-stacked strips of gasket at the back of the unit (which would hold the unit up off the normal 3/4" hard-foam pads and support the back of the pan). So I doubled up the hard-foam pads at the back to make them 1-1/2" thick and tightened the bolts till the 2" thick stacked square gaskets had compressed to 1-1/2". This left the bolts way looser than 40 in-lb. But if I go anywhere near that toque spec it'll pull the unit right down on the deck. I think I'll make some marks on the roof with sharpie so I can tell if is the units moves at all in transit and go from there.

Electrical: New units come with a mobile-home electrical connector pre-installed on the power cable. At least mine did... but Dometic only gave me 1 half of the connector pair. The connector is thin/flat and certified as a junction box. This opens up some additional room for airflow around the side of the duct (vs- the old steel junction box), so I bought the other half of the connector pair and used it. There are many variations of this Self-Contained Power Connector (SCPC), and here is the specific part if you need the other half for 12ga romex:

https://www.mouser.com/ProductDetail/molex/19045-1000/?qs=c7V%2bsbZfmqvqLYL%2bCrIKLw%3D%3D&countrycode=US&currencycode=USD

Noise: I was really hoping to wind up with a quieter unit. It is not, unfortunately 😒. In fact my iphone dB meter says it's about 2dB louder than my old center unit. Almost all of the noise is from the fan though. Pretty much can't hear the compressor at all. So, I'm going to experiment with some blocks of acoustic foam on the duct sides directly beneath the evaporator intake and see if I can trap some of the fan noise rather than let it come straight down through the filter. Initial experiments with wadded up kitchen towels were encouraging.

Cheers,

Walter

 

wow,

what a great post.  I assume (my memory) that you put back in a Penguin II and not the other Dometic (name escapes me) that would require a bit more "mod" but had about 25% more CFM.

You just proved what the LD instructor said.  I started torquing mine.  If I had, it would have been a disaster.  Sometimes we Engineers write silly specs just to impress folks...BUT, having a GOAL of 40 - 50 inch pounds and getting them SNUG leaves a lot to interpretation.

Thanks again for the update.

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Thanks!

Another update on the acoustic foam. I ordered some 3" thick foam and cut 2 blocks about 6"x3"x1-1/2" and tucked them up on the sides of the duct, directly beneath the evaporator intake. This blocks the path straight down from the evaporator.

Subjectively, they cut down quite a bit on the perceived fan noise. The higher-pitched blower whine is gone. Mostly what I hear now is a lower-pitched rushing of air and a little hum from the compressor.

My unscientific iPhone dB measurements read 2-3 dB difference with and without the foam blocks, with some visible reduction in volume between about 1000 and 5000 hz.

According to the dB meter, the new front unit still isn't any quieter than the old middle unit. But subjectively, I'd say its a big improvement.

Cheers,

Walter

foam blocks.jpg

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