Community Forums

bkc914 · 09-08-2018, 08:21 AM

hi all,
have 2003 dolphin, seems the condenser fans never come on.
have schematics for 2004 national rv,workhorse.does anyone have schematics from 3 knob controller to the chassis. a/c works great, 55-60 deg air out of dash ducts. compressor comes on as advertised

thanks
kevin

CJ7365 · 09-08-2018, 05:51 PM

My condensor fans turn on about a minute after i turn the A/C on.

You could check the relay in the front fuse box to see if its bad, swap it out with the A/C compressor relay.

You could uplug the connection for the fans and check voltage with a meter.

Also you might get some more suggestions if you ask a moderator to move this to the Workhorse chassis forum.

powerboatr · 09-08-2018, 05:53 PM

55 to 60 is not cold enough
but yes condensor fans should run once the condensor gets hot. there is a pressure switch that will turn them on.

Civdiv99 · 09-08-2018, 07:04 PM

Never? Or not while you are looking at them?

Mine don’t automatically come on when AC is engaged. When I recharged the system after replacing the compressor the system was running, AC engaged, while I was charging. No particular hurry I bet it ran for a good 1/2 hour whilst I was charging this and checking that, cold air a blowing. Then what seemed to me out of the blue, we’ll after I was done adding 134, but no doubt making perfect sense to the designers, they just “came on.”

I just now walked out to the coach, started it up, cranked on the dash air, opened hood, and... nope, they’re just free wheeling. Waited a few min, shut it off. Yet dash air works great and as recently as this past week on a trip. I didn’t stand there watching them, tho’ because I have seen them come on. Just not at my beck and call.

I personally wouldn’t worry about it to the point of tearing things apart unless you have other evidence of bad tidings beyond not catching them in the act.

Edit: Dang this post, now I’m curious. Heading out to see when/if they activate sitting in the driveway with AC on. It’s only about 74 or so out, though...

Civdiv99 · 09-08-2018, 08:04 PM

I’m back!

Just under 10 min running AC idling and the fans came on. Thinking about my above post and 30 min WAG, and given some of that time was spent adding 134, this seems about what I experienced before.

OP, as CJ suggested you can swap the 2 relays, and if the AC still engages, then the relay was fine. Otherwise you are at the mercy of the thermostatic control sending the signal to the relay to activate the fans. You can jumper the pin 30to the pin 87 (see bottom of relay) to force them on. Just to go on record, if you goof and smoke something, I’m suggesting against getting that medieval in the absence of other factors.

Also - inside the hood to the left be the lines to the evaporator. The lower (I think) line with the valve port is the outlet and should be cold during operation. If only cool, suspect low charge. The other line is from the condenser and should be fairly warm during operation. If it’s not warm at a minimum, not only won’t the fans be coming on, but you may be low on charge (thus fans never triggered). If it’s “dayum, that’s kinda hot” type of hot, then I’d be wondering if the fans shouldn’t oughta be running to help cool that down and condense it before heading into the evap, confirming your concerns. If you need more data I’m cool (bahahaha) with using my temp sensor pointer thing and giving you more specifics on those temp descriptions. Tomorrow.

So for frame of reference, my system has a new compressor and freshly charged. Line into the evaporator during this test was slightly? warm to the touch, but not approaching what I would call hot. Outside air temp maybe mid-70s or so. Low humidity. The air into the cabin was cold (no I didn’t measure it; I define the standard to be met, which is “civdiv99 felt it was cold”)

And the fans came on at 9 min and change.

Richard S. · 09-09-2018, 06:23 AM

The dash air system is Evans Tempcon and workhorse. link below

Evans Tempcon > Troubleshooting, Diagnosis and Repair

bkc914 · 09-09-2018, 01:20 PM

thanks to all for info

kevin

Pschweizer · 09-09-2018, 01:43 PM

YES It should come on. usually around or attached to the dryer is a pressure switch that turns on the fan. after a few minutes after the fluid in the system heats up so check for voltage at the fan should be 12 VDC. I just replaced my fan (it was burned out however the fan shaft did spin) We evacuated and recharged my Cab A/C system I get 46 degrees out of my dash vents and the outside ambient temperature is 108 degrees mid day in AZ.

bkc914 · 09-16-2018, 11:33 AM

ok guys i need an hvac genius
as per previous post condenser fans do not come on, a/c works great. swapped out relay, no help. fans check good.
checked relay with ohm meter, ok.
pulled relay, engine not running , have 13.5v on pins 30 & 85, open on pins 86 & 87.

next move may be engine running , relay pulled , max a/c and check voltages at pins 85,86,87.

anyone have suggestions, if not i think ill leave the damn thing alone as per civ div suggestions

CJ7365 · 09-16-2018, 11:46 AM

Quote:

Originally Posted by bkc914

ok guys i need an hvac genius
as per previous post condenser fans do not come on, a/c works great. swapped out relay, no help. fans check good.
checked relay with ohm meter, ok.
pulled relay, engine not running , have 13.5v on pins 30 & 85, open on pins 86 & 87.

next move may be engine running , relay pulled , max a/c and check voltages at pins 85,86,87.

anyone have suggestions, if not i think ill leave the damn thing alone as per civ div suggestions

All i can add is that the Workhorse Chassis guide states that the PCM controls the condensor fans, either when the a/c is on or if the coolant temp rises to above 221

I know it would be benificial to have those fans going, so instead of troubleshooting through the PCM, I would wire up a seperate realay and switch to control it manually from inside the RV.

10EC · 09-19-2018, 07:50 PM

Quote:

Originally Posted by bkc914

ok guys i need an hvac genius
as per previous post condenser fans do not come on, a/c works great. Swapped out relay, no help. Fans check good.
Checked relay with ohm meter, ok.
Pulled relay, engine not running , have 13.5v on pins 30 & 85, open on pins 86 & 87.

Next move may be engine running , relay pulled , max a/c and check voltages at pins 85,86,87.

Anyone have suggestions, if not i think ill leave the damn thing alone as per civ div suggestions

i aint a genuis but, look at the digram on your relay, should have 85 & 86 the coil these two wires are the hot and ground to make the relay coil work.
with no power to #85/86 #30 and #87a will be closed/in contact while at the same time #30 and #87 will be open/not contacted.
with power on to #85/86 #30 and
#87 will now be closed/in contact while at the same time #30 and #87a will be open/not contacted.

all the relay is doing is moving coninuity (POWER) from/to #30&#87A or to #30&#87. 87A OR 87 IS WHAT YOU ARE FIRING UP OR KILLING. If you power #85 &#86 you should feel & hear the relay coil energize.

HOPE THIS HELPS

Scooter · 10-27-2018, 09:01 AM

To the OP.......what is the latest, please ?

biker-bob · 10-29-2018, 09:55 AM

Quote:

Originally Posted by bkc914

hi all,
have 2003 dolphin, seems the condenser fans never come on.
have schematics for 2004 national rv,workhorse.does anyone have schematics from 3 knob controller to the chassis. a/c works great, 55-60 deg air out of dash ducts. compressor comes on as advertised

thanks
kevin

While working on a c , I read an article that stated w22 a c fans 2002 back came on when motor was started and a c turned on. 2003 and up , fans come on when engine temp reaches 190 and work off and on as a c compressor cycles. Ck. Evans Tempcom website , My 2004 Dolphin w22 does this exactly the same as the article describes.

bkc914 · 10-31-2018, 11:47 AM

i quit messing with it,,,, hard wired lighted switch where aux switch was on the dash,...turn it on when ever i use the a/c or when doing a long uphill pull

thanks kevin