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Topic: coach dash heater output/cruise control (Read 1141 times) previous topic - next topic

coach dash heater output/cruise control

OK, I'm driving along, engine warmed up, with heat pouring out of the the dash or floor vents.  I set the cruise control to a speed, and within minutes, the heat output drops off significantly, followed by complaints from my wife.  When I hit cancel on the cruise control, the heat slowly comes back, and the complaints stop.  I know it sounds crazy, but I have observed this for several years.  Any ideas?  It is not my imagination.

Bill Schlaudecker
2000 U270
Bill Schlaudecker
2000 U270 36'
2006 Jeep Liberty

Re: coach dash heater output/cruise control

Reply #1 –
Is the question, "How to fix my heater," or "How to stop my wife's complaints?" (Running and Ducking.... ;o)

Quote
OK, I'm driving along, engine warmed up, with heat pouring out of the the dash or floor vents. I set the cruise control to a speed, and within minutes, the heat output drops off significantly, followed by complaints from my wife. When I hit cancel on the cruise control, the heat slowly comes back, and the complaints stop.  I know it sounds crazy, but I have observed this for several years. Any ideas? It is not my imagination.
1999 U320 40' 1200 watts on roof. 12cf AC/DC Cold plate fridge/freezer. VMS 240 CL Honda Element

Re: coach dash heater output/cruise control

Reply #2 –
Does the volume of air coming out decrease, or just the temp of the air?
Steve & Ginny Hill
96 U295 36'/Wrangler
Tampa

Re: coach dash heater output/cruise control

Reply #3 –
Bill,
Can you tell us if the volume of air from the vents stays the same or is reduced with the cruise control engaged?  Also, in the winter, it may be advisable to close the "motoraid" valve to the hot water heater to increase the output of hot fluid to the heater core.  [Caveat: assumes you have a hot water heater and not an Aquahot.]
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: coach dash heater output/cruise control

Reply #4 –
Need to determine what is common between the cruise and heater.  I would bet it is vacuum.
Bill and Doris
93 GV gas

Re: coach dash heater output/cruise control

Reply #5 –
The airflow from the vents does not change.  Just the temp drop.  I do have the hot water valve closed.  When I have cruise control not set to a speed, my heat output is quite good.

Bill Schlaudecker
2000 U270
Bill Schlaudecker
2000 U270 36'
2006 Jeep Liberty

Re: coach dash heater output/cruise control

Reply #6 –
Bill,

You got me thinking, so, since I was on the road today I did some playing with switches...now, I am really comfused.  No air running on dash, temp setting as low as it will go....THEN, when I use the retarter, temperature goes way up. So much so the only way to lower it is to RAISE the lowest cool setting to mid way..then everything is fine again.....and no, I am not making this up.  Happens every time.  :-\ ::)
We are only strangers until we meet; however, some of us are stranger than others

Re: coach dash heater output/cruise control

Reply #7 –
I'm not sure but, Jeff, in your case I can see this happening as when the retarder is engaged, all the energy it's absorbing is being transfered to the trans fluid which gets cooled in the same area as the coolant.  It could then be raising the coolant temperarure and thus providing you with all that extra boost of dash heat.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: coach dash heater output/cruise control

Reply #8 –
When the retarder is activated, cruise is automatically disconnected so there is that common element.  But I can't make a connection to the heater.

Bill Schlaudecker
Bill Schlaudecker
2000 U270 36'
2006 Jeep Liberty

Re: coach dash heater output/cruise control

Reply #9 –
Bill, I can't imagine how your condition is created.  Is your dash heater control managed electrically , or is it a mechanical wire type control?  If it's electronically contolled, then start looking where these wires (cruise & heater) meet.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: coach dash heater output/cruise control

Reply #10 –
From my experience if Bill's heating valve is electrical, there is a bad ground either to the heating switch or cruise control. Now the fun part, finding it. If the valve is not electrical, well then I have no idea.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: coach dash heater output/cruise control

Reply #11 –
Don't they both use the same 12 volt vacuum pump?
1994 U225
build #4514

Re: coach dash heater output/cruise control

Reply #12 –
Check and see if the heat starts coming out of the defroster vents. It has to go somewhere and the default for no vacuum is the defroster vent.  IT may be partially closing and going up not towards you.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon