Charging a custom system.

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Legitness211
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Re: Charging a custom system.

Post by Legitness211 »

Well now that I was trying to get some refrigerant out of the system, I get the temperature from 17.5°C to 14.9°, and I think I remove a little too much because the temperature became rising to 15.8°C.

I will try to fix the problem of the exhaust manifold and airflow to see If I can get better temperatures.
tbirdtbird
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Re: Charging a custom system.

Post by tbirdtbird »

Well that is 59*F, which is better but not enough.
You really need to start all over, you have air in your system

Google this insulating blanket and wire it in place around either the exhaust or the comp, also any hoses
Aerogel Insulation Hydrophobic Mat of High Temp. Blanket 12''x12'',Thickness 10MM

You have multiple issues that are fighting you.

AC cannot be done in a half-ass manner and actually work
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
Legitness211
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Re: Charging a custom system.

Post by Legitness211 »

tbirdtbird wrote: Wed Sep 27, 2023 3:06 pm Well that is 59*F, which is better but not enough.
You really need to start all over, you have air in your system

Google this insulating blanket and wire it in place around either the exhaust or the comp, also any hoses
Aerogel Insulation Hydrophobic Mat of High Temp. Blanket 12''x12'',Thickness 10MM

You have multiple issues that are fighting you.

AC cannot be done in a half-ass manner and actually work
Ohh I forgot to mention something about the air in the system. I was confused, I dit not let air in the system, but actually I let a little bit of gas to escape from the low side, because all that I did was to open the low side a little bit by mistake while the AC was turned on, so we can remove that from the list of problems.

Now, correct me if I'm wrong, but if I was removing gas from the system, and if at some point the temperature started to go up insted of dropping, that means that I have reached the right amount of refrigeran?

And I'm going to address with the insulation, thank you for your advice. I will be updating with the results.
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JohnHere
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Re: Charging a custom system.

Post by JohnHere »

In your first post, the low-side pressure was 36 PSI, which means that your evaporator is running 40°F or a bit higher, too warm for decent cooling.

What kind of TXV does your Civic have, a block-type or one having a sensing bulb?
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Legitness211
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Re: Charging a custom system.

Post by Legitness211 »

JohnHere wrote: Thu Sep 28, 2023 6:58 am In your first post, the low-side pressure was 36 PSI, which means that your evaporator is running 40°F or a bit higher, too warm for decent cooling.

What kind of TXV does your Civic have, a block-type or one having a sensing bulb?
I have a TXV with a sensing bulb, I remember that when the people on the AC shop putted all together they get the TXV from an old car they had around, so all the AC components where new, but the TXV no. So I always wanted to change the TXV for that reason, but again, I don't have a lot of knowledge about this specific part, so I don't know how to tell if it is working good. Someone told me that you can adjust TXVs, do you think that could help?.
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tbirdtbird
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Re: Charging a custom system.

Post by tbirdtbird »

I have to admit that this has become one of the most confusing threads I have ever seen here. If we look back at April 2022 it gets even more confusing. Back then It was determined that the proper charge was 23 or 24 oz of refrigerant, so how did we land here now with wanting to use plateau method? NOT necessary.
Further, looking at 2022, Ice-N-tropics, a very sharp consultant, posted this:

"FYI: Civic engine rotates CCW. SDS508 Sanden spec is CW rotation because of gear engagement timing verses piston TDC. Timing has a large effect on compressor noise and may decrease compressor life 10% to 25% but pumping capacity is OK.
Chinese knockoff rotation unknown.
Sanden Singapore makes one model SD508 that is rated CCW only."

This very important question was never addressed, and should be.
We are being given conflicting info: one time you say you let air in while you were switching cans (a common problem I might add) then you say that was not so.
Also, some of us here on the forum are still not convinced the condenser is installed correctly. We need pictures.

Also, you may have what we call re-heating, ie heat from the heater core can wash over the AC evaporator and kill the cooling effect. This can be due to damper doors not functioning properly or the foam seals all rotted off the edges. I wonder about this because in 2022, you said you had a low side pressure of 36 psi, which is not far off the desired pressure at all, and should have gotten you about 40*F center vent, which is rather decent cooling, especially compared to the 59*F you have now.

I am not convinced any part of this system has been done correctly, and used parts have been installed, and who knows if they are any good.

I am thinking we have to start from the beginning. We have to be certain of the integrity of all of the components. All of the potential issues we have raised need to be addressed. And the compressor is so close to the exhaust that it is ridiculous and cannot possibly work correctly.

Did the AC ever work in this car at all??
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
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JohnHere
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Re: Charging a custom system.

Post by JohnHere »

A couple of issues come to mind about the TXV. The first is that we don't know for certain whether the TXV the shop installed is any good. The second is that the sensing bulb is wrapped in what looks to me like duct tape, which isn't sufficient as far as insulating properties are concerned. It's likely that the sensing bulb is picking up heat from the engine compartment. If that's the case, then the TXV won't get the correct signals to operate properly. And hence, your A/C system won't work right. I wouldn't suggest that you try adjusting it, either.

If the car were mine, I would replace the TXV with a new one from Honda. The reason I say that is because over the past few years, some aftermarket TXV's have been known to give problems, requiring that the job be done over, which I'm sure you want to avoid. Additionally, you'll need to ensure that the sensing bulb is securely fastened to the suction-side tube using the original clip(s), and that it's well insulated. The pros use a product called Prestite Tape, which you can probably get locally from an HVAC supplier in your country.

To replace the TXV, you'll have to recover the system so that there's zero pressure in it.
Legitness211
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Re: Charging a custom system.

Post by Legitness211 »

tbirdtbird wrote: Thu Sep 28, 2023 10:36 am I have to admit that this has become one of the most confusing threads I have ever seen here. If we look back at April 2022 it gets even more confusing. Back then It was determined that the proper charge was 23 or 24 oz of refrigerant, so how did we land here now with wanting to use plateau method? NOT necessary.
Further, looking at 2022, Ice-N-tropics, a very sharp consultant, posted this:

"FYI: Civic engine rotates CCW. SDS508 Sanden spec is CW rotation because of gear engagement timing verses piston TDC. Timing has a large effect on compressor noise and may decrease compressor life 10% to 25% but pumping capacity is OK.
Chinese knockoff rotation unknown.
Sanden Singapore makes one model SD508 that is rated CCW only."

This very important question was never addressed, and should be.
We are being given conflicting info: one time you say you let air in while you were switching cans (a common problem I might add) then you say that was not so.
Also, some of us here on the forum are still not convinced the condenser is installed correctly. We need pictures.

Also, you may have what we call re-heating, ie heat from the heater core can wash over the AC evaporator and kill the cooling effect. This can be due to damper doors not functioning properly or the foam seals all rotted off the edges. I wonder about this because in 2022, you said you had a low side pressure of 36 psi, which is not far off the desired pressure at all, and should have gotten you about 40*F center vent, which is rather decent cooling, especially compared to the 59*F you have now.

I am not convinced any part of this system has been done correctly, and used parts have been installed, and who knows if they are any good.

I am thinking we have to start from the beginning. We have to be certain of the integrity of all of the components. All of the potential issues we have raised need to be addressed. And the compressor is so close to the exhaust that it is ridiculous and cannot possibly work correctly.

Did the AC ever work in this car at all??
First, thankyou tbirdtbird for taking the time to review all that information from 2022.

Ok let me clarify things up.

Back in 2022 the main problem was the condenser being installed upside down, I fixed the issue, and the AC started to work better, but never great. Of course with recirculation on, and driving for a couple of minutes you can get to a confortable temperature, not so great during very hot days specially, but I got tired of trying to find the issue and trying to find the correct amount of refrigerant. And I think we have to ignore all the pressures and temperature readings back then because I had little to no knowledge about car AC, so most of those reading were registered in idle and with all doors and windows closed.

A couple of weeks ago I damaged the condenser, so I had to buy a new one, and that's when I asked for information about the appropriate size and the correct plumbing of the hoses, because I like to be sure when I do something. So yes, I'm really sure the condenser is connected correctly, I Will post pictures later because right now I'm not at home.

Talking about the heater core, I personally restored the climate control assembly back in 2022, and I double checked about 2 days ago that there is no coolant passing through the heater core and that the blend door is working and in the correct position. Buuut, I have to mention, and I'm going to post pictures, about a place in the firewall where some Air can possibly enter near the evap.

And as I mentioned, I did not let air into the system while charging, I just oppened the low side a little bit by mistake while the car was running, letting a little refrigerant go out.

The only used part of the system is the TXV.

Now I have a little bit more knowledge about car AC, so I can test the performance with correct procedure, and the lowest temperature I can get at about 12MD-1PM is 16°C and at night is 11°C.

So my big concerns are:

-Find the correct amount of refrigerant. I have tried with 12oz and 24oz but I don't see any improvement, that's why I would like to try with the plateau approach and do It correctly.
-Airflow and Heat from the exhaust, I have to mention that I went for a ride last night, and with the Highway Air at 80km/h the vent temperature only dropped 1-2°C, so that could suggest that the problem is not airflow?
-The TXV since It is the only used part of the system.
Last edited by Legitness211 on Thu Sep 28, 2023 1:43 pm, edited 1 time in total.
Legitness211
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Re: Charging a custom system.

Post by Legitness211 »

JohnHere wrote: Thu Sep 28, 2023 10:51 am A couple of issues come to mind about the TXV. The first is that we don't know for certain whether the TXV the shop installed is any good. The second is that the sensing bulb is wrapped in what looks to me like duct tape, which most likely isn't sufficient as far as insulating properties are concerned. It's likely that the sensing bulb is picking up heat from the engine compartment. If that's the case, then the TXV won't get the correct signals to operate properly. And hence, your A/C system won't work right. I wouldn't suggest that you try adjusting it, either.

If the car were mine, I would replace the TXV with a new one from Honda. The reason I say that is because over the past few years, some aftermarket TXV's have been known to give problems, requiring that the job be done over, which I'm sure you want to avoid. Additionally, you'll need to ensure that the sensing bulb is securely fastened to the suction-side tube using the original clip(s), and that it's well insulated. The pros use a product called Prestite Tape, which you can probably get locally from an HVAC supplier in your country.

To replace the TXV, you'll have to recover the system so that there's zero pressure in it.
Yes the sensing bulb is attached with the original clips, and they said that the TXV is an OEM one they got from a civic or prelude, I don't remember, but of course it was used, and yes it is just wrapped with aluminum tape and duct tape, so I guess I will have to get some of that Prestite Tape.

Talking about the TXV, is there a way of testing if it is deffective?, It would be better to modify the lines and to install a block TXV, or just to replace it with the same type of TXV

If only we had professionals like you all in my country, I would not be in this nightmare.
tbirdtbird
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Re: Charging a custom system.

Post by tbirdtbird »

The clarifications you have offered are a help, but we have a ways to go.
1. Direction of rotation has not been clarified
"FYI: Civic engine rotates CCW. SDS508 Sanden spec is CW rotation because of gear engagement timing verses piston TDC. Timing has a large effect on compressor noise and may decrease compressor life 10% to 25% but pumping capacity is OK.
Chinese knockoff rotation unknown.
Sanden Singapore makes one model SD508 that is rated CCW only."
So based on the comp model you bought determine the specifications and thus whether it is a CCW or CW comp.

2. The amount of refrigerant will be close to the originally specified amount, no need to complicate things by trying to figure out the plateau method.
3. If you only damaged the condenser, why are you replacing the comp?
4. It is difficult to determine if the TXV is any good. That is why John is suggesting that you get a new one. And, yes, the bulb must be insulated. If it is wrapped in aluminum tape, that is only going to ADD heat to it, and not insulate it.
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
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