Re charging dash AC

Topic: Re charging dash AC (Read 2022 times) previous topic - next topic

Re: Re charging dash AC

Reply #25 – January 20, 2017, 03:28:07 pm

Well I could have taken my coach in and had it repaired as someone has suggested. But I'm one of these guys that knows nothing and asks for help. Well ok I know a little. Anyway I think Wyatt has hit on something. First I checked voltage at compressor and there is none. I then checked voltage at sw. on the accumulator and there is none. And I did find the fuse Wyatt is talking about and mine is very rusty also. After the fuse it feeds a relay that feeds the AC compressor and thermo dash ac. My fuse is hanging by its wires. I will get my fat self under the coach and change out fuse. then we will see what happens. You are never to old to learn and I am learning alot from all of you.

Re: Re charging dash AC

Reply #26 – January 20, 2017, 04:26:52 pm

Checking the clutch is very easy:

With engine OFF, disconnect the wire going to the clutch (there is only one).

To the A/C clutch side, apply 12 VDC positive from any source (the remote start switch is an easy place to use as a source).

You should hear and see the clutch pull in.

This also works (only use temporarily) if you think your low pressure switch is preventing you from adding Freon/134A.

Re: Re charging dash AC

Reply #27 – January 20, 2017, 05:57:42 pm

Thanks Brett, but I think based on Wyatt's post I'm hoping it will allow me to add freon after I replace the fuse. I will check the fuse before replacing but based on its condition its probably shot. If fuse proves to be good I will then put a 12v source to the compressor clutch. I will report progress.

Re: Re charging dash AC

Reply #28 – January 20, 2017, 07:21:12 pm

Source for the fuse?

Re: Re charging dash AC

Reply #29 – January 22, 2017, 07:11:26 am

FYI,you can get a 30lb can of r134 from amazon for $120,will last a lifetime,but you will need
Gauges,those small cans add up quick.Plus you can use it for your car.

Re: Re charging dash AC

Reply #30 – January 22, 2017, 08:34:16 am

You can get a 30lb tank of R134A at Rural King for $99.99 if you have one near you.

R134a Refrigerant 30 LB Cylinder 6330 by Technical Chemical for .99 in...

Also;

Auto A/C Manifold Gauge and Hose Set, R12 R22 R502 R134A - Walmart.com

Re: Re charging dash AC

Reply #31 – January 22, 2017, 09:17:24 am

Well here is my update. Replaced 15 circuit breaker that Wyatt spoke about and then jumpered out compressor as Brett suggested. Freon flowed freely and put in about 22ounces of freon . With compressor jumpered out the discharge air is ice cold but as soon as I pulled jumper off, the compressor disengaged. There is no voltage at the compressor. I don't know where the low pressure sw is. It appears that as someone earlier said this may not be a freon or leak issue. By the way I purchased the 15 amp breaker at a local Car Quest. Where should I go next?

Re: Re charging dash AC

Reply #32 – January 22, 2017, 09:25:47 am

What was your pressure with the compressor jumpered ? This is an electrical issue you will have to follow from the a/c switch to the compressor on the schematic for your coach. There is a relay, the a/c switch and high and low pressure switches to check out.

Re: Re charging dash AC

Reply #33 – January 22, 2017, 09:39:19 am

Craneman the pressure was 25 with compressor running. The circuit breaker gets its feed from a solenoid. Then it feeds a AC comp. relay. One side goes to ground. One side goes to AC compressor and one side goes thermo dash ac. Don't know where high and low pressures swiches are dwg. doesn't show. High and low fill ports are at the front of the coach behind passenger side head lights. There are numerous relays at the rear of the coach I will have to find the right relay. Its a wiring nightmare.

Re: Re charging dash AC

Reply #34 – January 22, 2017, 09:44:00 am

Howdy joeszeidel,
Since you think it may be an electrical problem, maybe this print will offer some help. The date on print is 1995, so hopefully, applies to your coach. Note: there is three pages to this .pdf.
Good Luck, Dave A

Re: Re charging dash AC

Reply #35 – January 22, 2017, 09:54:53 am

Dave Thank you for that PDF. I believe I know where those high and low sw. connections are. The fact that one is red and one is black will help. My checking will go on later this week. Bad weather is headed our way. These drawing will make sorting the wiring a little easier.

Re: Re charging dash AC

Reply #36 – January 22, 2017, 10:01:13 am

You can jumper the switches one at a time to check them or buy a tool which I have three of, one for my crane and one for the motorhome and one in my shop. This tool will save a lot of trouble shooting time. It lets you apply power or ground to whatever you are checking. This comes with a 20 extension cable which I use in the motorhome to make it easier.

Power Probe 319FTC-RED Test Light and Voltmeter - Walmart.com

Re: Re charging dash AC

Reply #37 – January 22, 2017, 10:13:29 am

Craneman with the dwgs I got from Dave I think I know where the high and low pressure sw's are and I have a very good volt meter. With the engine running and the ac switch on. I could check for voltage at each of these switches. If there is voltage then switch is bad. If no voltage the I have to find source. Am I correct?

Re: Re charging dash AC

Reply #38 – January 22, 2017, 10:21:41 am

You have to check that the power passes through the switches. Start at the A/C power switch and go from there. I am assuming your coach has a separate A/C switch for the compressor that starts the condenser fan and the compressor clutch. That is how my '99 is wired. You don't need to run the engine to do these checks, just ignition switch on.

Re: Re charging dash AC

Reply #39 – January 22, 2017, 10:26:33 am

Yes I have a seperate ac sw. on my dash which is easy to get to. Never thought that, that sw. could be bad.

Re: Re charging dash AC

Reply #40 – January 22, 2017, 12:09:56 pm

Check your temperature switch that is mounted to the outside of the evaporator box. It has a capillary tube that inserts into the evap coil.
check for voltage there and if present only on one side then temporarily jump it out. With a set of gauges hooked up you will see pressure drop on the low side and increase on the high side almost immediately, no need to run to the back of the coach for visual.

Contacts were bad in mine and got a new one from Napa.

Re: Re charging dash AC

Reply #41 – January 22, 2017, 12:18:41 pm

Dave the high and low pressure switches are not behind my compressor. I have a cat maybe thats why. The wire leading to the compressor is numbered 6310 but I dont have a diagram. Craneman I checked front sw and it has power I even jumpered out but no change. Weather is declining will continue later this week. Getting to the evaporator will be a pain. Oh well its beer and football later whats wrong with that.

Re: Re charging dash AC

Reply #42 – January 22, 2017, 12:26:59 pm

Looking at Dave's schematic, make sure you have power coming out of both relays.

Re: Re charging dash AC

Reply #43 – January 23, 2017, 04:45:17 pm

Went to the coach today and discovered I have 4 relays at the rear on the drivers side. Also found a red wire broken off of one of the relays. Replaced the plug but not the relay. Hooked back up but still no compressor running. There is 12v at both the pins marked 86 and 87. Will purchase a relay and start swaping them out. The relay I rewired may not be for the compressor. I don't know why I would have four relays.

Re: Re charging dash AC

Reply #44 – January 23, 2017, 05:34:04 pm

Howdy joeszeidel,
Not sure about 4 relays, but this attached electrical print, shows 2 relays associated with a/c system. See the dashed line outline near the bottom center of print. The devices (relays, isolator, solenoids, self-resetting 12vdc breakers, etc,) on this panel is located under the bed, in the front of the engine compartment, on driver's side. The print date is 1992, so hopefully, close to what your system may be.
Good luck, Dave A

Re: Re charging dash AC

Reply #45 – January 23, 2017, 05:46:37 pm

Hi Dave I will certainly check under the bed. I really have 4 relays all seem to be the same all mounted in about a 4 inch square area. I plan to buy a standard 5 blade bosch relay and start checking each one to see if I can get power to the compressor. thanks for your help

Re: Re charging dash AC

Reply #46 – January 24, 2017, 04:29:52 pm

Well I am in a funk. I said yesterday I had 4 relays. Turns out only 3. Dave none under the bed, they are all bunched together. Today I bought a relay and started switching them out to see if that would help. No help. I checked voltage at low pressure sw. on dryer and jumpered out the sw. Still no compressor. The condenser fan does run. The two 15amp breakers are fine. Don't know where to go next. Maybe the repair shop.

Re: Re charging dash AC

Reply #47 – January 24, 2017, 05:52:39 pm

Howdy joeszeidel,
If you're thinking of having a tech look at the problem, one of the very best is in the area. Might be worth a call.
Paul Yasbeck
(Foretravel Savvy with multiple recommendations)
813 382 0869
120 Ice Cream Rd.
Leesburg, FL
Good luck, Dave A

Re: Re charging dash AC

Reply #48 – January 24, 2017, 07:34:17 pm

Thanks Dave, I know Paul have worked with him before.

Re: Re charging dash AC

Reply #49 – January 24, 2017, 09:41:13 pm

Check back in if you get it solved, good information for possible future problems.

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