Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×
RV Trip Planning Discussions

Go Back   iRV2 Forums > THE CHASSIS CLUB FORUMS > Workhorse and Chevrolet Chassis Motorhome Forum
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
Thread Tools Search this Thread Display Modes
Old 11-12-2019, 04:41 PM   #1
Junior Member
Join Date: Jun 2019
Posts: 17
Heater Problem

2005 Monaco Lapalma 8.1 litre gas. My coolant temp gage shows midway, the heater blows cold until the revs are above 2100 rpm. Any ideas, heater hose on off valve works fine.
Keithdee is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free! RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 11-12-2019, 06:58 PM   #2
Senior Member
National RV Owners Club
Join Date: Mar 2012
Location: Lac Du Bonnet, Manitoba
Posts: 685
I've owned two W22 chassis RV's (05 & 08) that, in cold weather, blew only "luke warm" air from the dash vents with the heat on full HOT. It is slightly warmer when driving with the engine working. They've both used the Evans-Tempcon HVAC system, Measuring the warm air temperature coming out of the dash shows it's not even close to the heat from a typical car or truck. Checking the coolant on/off valve on the input side of the heat core showed it was working correctly. I even bypassed it with a hose around the valve but made no difference. My engine temperature on the scan gauge is 190 degrees like any car or truck. So the engine has lots of heat available..

Years ago we, as many others, put up a spring loaded shower curtain pole near the ceiling behind the front seats with floor to ceiling drapes which helped keep us warm while driving when it's cold.
One suggestion I just read from another owner was to disconnect the heater core hoses and reverse flush the heat core and capture what comes out. He claimed all sorts of "crud" came out and there was more heat after. I'll try this next spring.
Ellen & Greg
08 National Dolphin DL-35Ci, RoadMaster Rear Sway Bar, Rear Trac Bar, Koni Shocks Front,
Workhorse W22, Kelderman Air Ride, Towing 2016 Smart Car
GREGORYJ is offline   Reply With Quote
Old 11-12-2019, 08:41 PM   #3
Senior Member
Full-Timers's Avatar
Workhorse Chassis Owner
Rexhall Owners Group
Join Date: Feb 2003
Location: Everywhere,USA
Posts: 1,517
I would start feeling heater hoses. If you have a hot hose coming from the engine to the valve and Luke warm on the out-side of the valve, it's the valve or control voltage to the valve. If it is hot on the in-side of the heater core and Luke warm one the out-side of the heater core it's a plugged heater core. If it's hot coming out of the heater core it's could be a duct disconnect under the dash.

You need to do some simple troubleshooting.
in a
2003 Rexhall Aerbus 3550BSL
W22 Workhorse
Full-Timers is offline   Reply With Quote
Old 11-13-2019, 06:55 AM   #4
Senior Member
vettenuts's Avatar
Join Date: Nov 2013
Posts: 5,749
Might also want to check that no critters built a nest in the heater box.
2015 Tiffin Phaeton 40QBH
2018 Chevrolet Colorado Toad
Roadmaster Tow Setup
vettenuts is offline   Reply With Quote
Old 11-15-2019, 10:23 PM   #5
Peep99's Avatar
Join Date: Aug 2019
Posts: 46
Maybe put in a hotter thermostat?
2003 itasca Sunrise ipF32v 8.1L w22
Front back sumo springs
Peep99 is offline   Reply With Quote
Old 11-16-2019, 07:48 AM   #6
Senior Member
akpd's Avatar
Join Date: Jul 2018
Location: NC
Posts: 234
Originally Posted by Keithdee View Post
2005 Monaco Lapalma 8.1 litre gas. My coolant temp gage shows midway, the heater blows cold until the revs are above 2100 rpm. Any ideas, heater hose on off valve works fine.
Mine dash gauge shows midway as well (OBDII info is 190-206), do you know if the dash heater A/C box fresh air door is closing?
2004 Monaco Lapalma PDT W-22, 8.1

FSE Industrial Ceramic Kilns.
akpd is offline   Reply With Quote
Old 11-16-2019, 10:57 AM   #7
Senior Member

Join Date: Jan 2009
Posts: 5,307
I may be thinking in reverse so not sure if this could cause this problem. Could it be the damper is not operating correctly because the vacuum line going to it has deteriorated?

There is a small blue vacuum line on the Workhorse that breaks down and disintegrates as time goes by. The one on my Workhorse did this and the damper would not work. Unfortunately, I can't remember if that caused a loss of heat or too much heat.
03 Itasca Sunova, Workhorse P32 with the 8.1 and 4L85-E
Mudfrog is offline   Reply With Quote
Old 11-16-2019, 03:44 PM   #8
Join Date: Oct 2012
Posts: 86
I have a 2004 P32 my evans valve leaks during ac operation so I flushed the heater core and and installed ball valves to shut off all water when using ac and it works great. Also when using full heat it will put out some serious heat when it is cold out side. No need for a curtain.
Wrenchch3 is offline   Reply With Quote
Old 11-16-2019, 06:46 PM   #9
Moderator Emeritus
"007"'s Avatar
Nor'easters Club
Workhorse Chassis Owner
iRV2 No Limits Club
Join Date: Oct 2004
Posts: 30,785
You will find EVAN's info in this link.
Could be the control valve is install backwards.
98KSCA, 99MACA, 03 KSCA-3740- 8.1 Chev-- ALLISON Trans
"007" is offline   Reply With Quote

heat, heater, problem

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Troubleshooting Refrigerator, Water Heater, Propane Heater on 2000 Coleman Santa Fe? Cheburashka Pop Up, Tent Trailer and Teardrop Topics 6 10-16-2012 06:24 PM
Engine Heater vs Block Heater patmsp Monaco Owner's Forum 4 09-29-2010 01:51 AM
Heater hoses going to water heater?? meworrynot RV Systems & Appliances 6 05-08-2010 09:54 AM
water heater ac heater failure dirko Winnebago Industries Owner's Forum 3 05-05-2009 12:29 PM
Water heater electric heater replacement dirko Winnebago Industries Owner's Forum 5 10-20-2005 10:53 AM

» Featured Campgrounds

Reviews provided by

All times are GMT -6. The time now is 02:22 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.