Dash a/c stopped working

[faye]

our dash air is not working on a 2004 natiional seabreeze with a 8.1 chevy engine. service tech said it need a valve(can't remember name) having a senior moment,,,,he said it regulated the freon thru the system...said he can not find the part number by going to workhorse or chevy???please help///since national is no longer in business..where does he go to cross reference the part??????????????thanks TECH SAYS IT SITS ON THE SIDE OF THE FREON TANK. NEED HELP ASAP PLEASE............

[GaryKD]

Hi faye,
I do not know National coaches. However, automotive parts should be industry standard parts. If it was me, I'd take the coach to a shop that specializes in auto A/C. It sounds like what the tech is saying you need is an expansion valve.

[deaton]

The valve he mentioned is probably the expansion valve.
You don't need to worry about this being a National. All the dash air conditioners used in these coachs are standard automotive designs and parts should be readily available for ANY of them.

Coincidently, the dash air on my 2008 Camelot went out recently and my coach is in the shop right now. I diagnosed the problem myself, and won't get into that here, but it was similar to what you are describing - a plugged expansion valve. The problem was caused by the drier canister, which sits immediatly ahead of the expansion valve in the freon circuit. Those drier's have a tendancy to come apart inside (especially when they are made in China - cheapest bidder and all - like mine was) and that can release the little silica drier pellets into the flow where it goes directly to the expansion valve and plugs it up - hence no more air conditoning. If you system still has pressure, particularly on the high side and it's pulling a vacum on the low side, this is probably your problem. If that's what your problem it, you will need a new drier, a new valve and the system will need to be purged, cleaned and recharged.

It's not too difficult or expensive a fix (like compared to a compressor/clutch) and it should cost you less than a grand - mostly labor - the parts are not that expensive.

Any good AC shop should be able to do this for you. I have a truck/chasis guy doing mine and given my past experience with this guy, I'm sure it will be done right and on time at a fair price.

[garym114]

Earlier nationals had EvansTempcon hvac units. If the control panel looks like any of these that is what you have got. Parts info on the site.
Evans Tempcon, Inc

[faye]

Originally Posted by GaryKD

Hi faye,
I do not know National coaches. However, automotive parts should be industry standard parts. If it was me, I'd take the coach to a shop that specializes in auto A/C. It sounds like what the tech is saying you need is an expansion valve.

this is the 2nd place we've taken it, one to a large truck/rv repair...they did nothing but charged us for freon and labor. told us nothing was wrong with the a/c. less than 10 minutes of driving and hot air again. we now have it at a chevy repair shop and in less than 30 minutes they were able to diagnose the problem and now that you.ve refreshed my memory, they did say the expansion valve. when they went on their computer to try to order the part...said they could not locate it...we are waiting now to hear if they were able to locate the right part for our national.
the first place kept it 8 days and we really do not believe they did anything except charge us. thanks for the replies.

[faye]

Originally Posted by garym114

Earlier nationals had EvansTempcon hvac units. If the control panel looks like any of these that is what you have got. Parts info on the site.
Evans Tempcon, Inc

we have the 2004 national seabreeze, with a chevy 8.1 engine, and a workhorse chassis.

[GaryKD]

Hi faye,
Neither place the coach has been specialize in A/C. Please consider taking the coach to a shop where auto A/C is their only/main business. The Yellow Pages may be a good place to find an A/C specific shop.

[faye]

Originally Posted by GaryKD

Hi faye,
Neither place the coach has been specialize in A/C. Please consider taking the coach to a shop where auto A/C is their only/main business. The Yellow Pages may be a good place to find an A/C specific shop.

this dealer is a chevy center who does alot of a/c work and we thought since it was not an rv dealer that the people would be more reputable....today we had not heard from them, and we went by and they are now telling us it is not the expansion valve but the actuator(not sure if i spelled this right) they say it is not switching from heater to a/c. anyone know anything about the actuator and what the cost may be???? we had not thought of a shop that does only a/c...we live in a rural area and not sure if we can find one...many places will not take a motorhome. your replies have been helpful...

[garym114]

faye - Did you look at the link to Evans in my post to see if you have their AC unit?
Look at the link to evanstempcon in my previous post and see if your control panel looks like any in the pictures.

The AC unit was added by national when they built the coach.

They have a troubleshooting section on their website.

[faye]

Originally Posted by garym114

faye - Did you look at the link to Evans in my post to see if you have their AC unit?
Look at the link to evanstempcon in my previous post and see if your control panel looks like any in the pictures.

The AC unit was added by national when they built the coach.

They have a troubleshooting section on their website.

we did look and think we have one of those, but motorhome is still in this last shop, we seem to be having such problems with each place we have had ours, i read on this forum there is a problem with the way workhorse designed the a/c and cooling and that none of them cool well. we just had ours in a wh center for left rear brake seizing, but these people did not work on a/cs. we only have 7,000 miles on the rv. thanks to all and as shop did not call us today we have no idea if it is the actuator or something else.

["007"]

If your dash AC has warm air coming out of it when in stop and go traffic your Evans valve is not completely closing off the heater hose from engine and you have hot water in your heater portion of AC/Heater unit.
You either replace the Evans valve, as Gary gave you, or install a ball valve in one of your heater hoses coming from engine.
Doing this will completely block heated water from heater and allow AC function on its own without having to over come the hot water in heater portion of unit.


You can see the Evans control valve to left of valve top hose entering the valve.
Your coach MFG installed the AC/heater.
Evans control. "AC Trouble shooting Guide"

[Max Hubrich]

Faye-

I recently had a new dash A/C compressor installed. It also required a new expansion valve. I have an '02 W-22.

Here are some numbers and pictures of the valve.

The valve is the shiny rectangular aluminum block-

It's from a '89 Jeep Cherokee. Auto Zone #157743 758901. $11 bucks.



New expansion valve installed and recharged. I recovered it with Prestite insulation




My new compressor is from an S-10 Blazer (Delphi). Car Quest #271569. $873 bucks.

Good advice on the other threads. Find a shop that specializes in A/C work.

Good luck,

[faye]

Originally Posted by 007";676868]If your dash AC has warm air coming out of it when in stop and go traffic your Evans valve is not completely closing off the heater hose from engine and you have hot water in your heater portion of AC/Heater unit.
You either replace the Evans valve, as Gary gave you, or install a ball valve in one of your heater hoses coming from engine.
Doing this will completely block heated water from heater and allow AC function on its own without having to over come the hot water in heater portion of unit.


You can see the Evans control valve to left of valve top hose entering the valve.
Your coach MFG installed the AC/heater.
[B][URL="http://evanstempcon.com/guides_ccl.php

Evans control.[/URL] "AC Trouble shooting Guide"[/B]

if you install the ball valve, would you turn this off in hot weather and then back on when the weather gets cold???????????

[faye]

this is such a nice group of such knowledgeable people. i've learned so much from all of the posts....my husband does not care for the internet but he always wants to know what i've found out on this forum..we've always had a 5th wheel and just never had much of anything he could not fix, but this motorhome is something else and your replies are so helpful. thanks to all of you