Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 01-23-2009, 09:05 PM   #1
Newbie
 
Join Date: Jan 2009
Posts: 5
Share |
Default

Comfortmaster RPJ II Open High Limit


Hello...Hopefully someone can guide me here. I have a Comfortmaster RPJ II, I am getting 4 flashing red lights. The diagram on the furnace indicates an open high limit switch. I replaced the filter and I have the same issue. the furnace will run fine without the filter installed. I removed the blower and cleaned it out there was a lot of dirt on the fins of the blower. I removed what I think is the limit switch and wiped off its surface. I checked all of the vents and made sure they were all open and none of the return vents are blocked. Needless to say still the same issue. Any ideas??? Thanks in advance.

I forgot to mention it is a downflow furnace and the limit switch I checked is the upper one. Checking the lower one now...


Last edited by khalidmo81; 01-23-2009 at 09:47 PM. Reason: add more info
khalidmo81 is offline   Reply With Quote
Old 01-24-2009, 04:53 PM   #2
Newbie
 
Join Date: Jan 2009
Posts: 5
Default

Comfortmaster RPJ II Open High Limit


Reading through previous posts I understand now that cause could be an air flow problem. I was reading elsewhere that the AC coils may be dirty and require to be cleaned. Being that it is a down flow furnace and the AC coils sit on the bottom, if I remove the coils for cleaning could the furnace fall or should it be supported somehow?

khalidmo81 is offline   Reply With Quote
Old 01-24-2009, 10:33 PM   #3
Member
 
Dr Heat's Avatar
 
Join Date: Jan 2009
Location: Northern Central IL
Posts: 94
Default

Comfortmaster RPJ II Open High Limit


depending on how the coil was installed you may need to pull the furnace to clean it.

Now if the coil is in a factory supplied cabinet or the installer made it accessible you may be able to remove the front and clean it.

You should be able to get your hand in without pulling the coil.
If you do need to pull the coil do not kink the copper lines.

This should be a DYI but be gentle you could easily bend the coil fins or kink a line and all your savings are gone.
Dr Heat is offline   Reply With Quote
Old 01-25-2009, 09:30 PM   #4
Newbie
 
Join Date: Jan 2009
Posts: 5
Default

Comfortmaster RPJ II Open High Limit


THANKS! I will try it tomorrow evening. It looks like the installer did leave an access panel at the bottom of the furnace.

One more questions, at my dads house there is a vent that has a handle labeled summer and winter, like some kind of damper, is this supposed to be available on all HVAC systems?
khalidmo81 is offline   Reply With Quote
Old 01-28-2009, 03:22 PM   #5
Newbie
 
Join Date: Jan 2009
Posts: 5
Default

Comfortmaster RPJ II Open High Limit


I was able to remove the front cover off and clean the coils. Wow they were caked with dirt. I popped the filter in and sat in front of the unit for 30 minutes...it works like new again. The airflow coming from the ducts is a lot better. Can't wait for summer clean the exterior condenser and start the AC.

Thanks Dr Heat for your advice.
khalidmo81 is offline   Reply With Quote
Old 01-28-2009, 03:32 PM   #6
Member
 
biggles's Avatar
 
Join Date: Jan 2008
Location: Long Island
Posts: 3,626
Default

Comfortmaster RPJ II Open High Limit


filter...squirrel...coil is how that dirt travels at least your good for the winter.plan on doing a liquid wash on that evaporator for the summer to get the dirt between those coils out.
biggles is offline   Reply With Quote
Old 01-28-2009, 03:37 PM   #7
Member
 
JohnH1's Avatar
 
Join Date: Jan 2009
Location: Chicago, IL.
Posts: 428
Default

Comfortmaster RPJ II Open High Limit


Quote:
Originally Posted by khalidmo81 View Post
THANKS! I will try it tomorrow evening. It looks like the installer did leave an access panel at the bottom of the furnace.

One more questions, at my dads house there is a vent that has a handle labeled summer and winter, like some kind of damper, is this supposed to be available on all HVAC systems?
This handle is probly on the humidifier. Open in winter and closed in the summer. But not all humidifiers have them. and not all furnaces have humidifiers.
JohnH1 is offline   Reply With Quote
Old 01-28-2009, 03:43 PM   #8
Newbie
 
Join Date: Jan 2009
Posts: 5
Default

Comfortmaster RPJ II Open High Limit


I bought the house 2.5 years ago, this is my third winter there. When I moved in the previous had the wrong size filter in the unit, it was 2 inches to small and to top that off - it was the cheap 30 day kind (probably has not been changed for 6 months), the humidifier filter was never changed or cleaned, there was so much hardwater build-up on the filter and the inside of the humidifier that it leaked out of the unit onto the floor and damaged the walls.

All that to the side - any pointers on cleaning the condenser?
khalidmo81 is offline   Reply With Quote
Old 01-28-2009, 03:47 PM   #9
Member
 
JohnH1's Avatar
 
Join Date: Jan 2009
Location: Chicago, IL.
Posts: 428
Default

Comfortmaster RPJ II Open High Limit


Turn off the power remove the top or whatever panal is neccessary to be able to wash it from the inside out. IE: the oppisite direction of airflow.

JohnH1 is offline   Reply With Quote
Reply


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
comfortmaker - 4 blink error - "open high limit switch" ericro HVAC 17 01-19-2009 09:36 AM
Diagnostic Code: Primary Limit Circuit Open arete01 HVAC 2 12-30-2008 07:44 PM
Trane Open High Limit Device mdcheddarhead HVAC 3 03-02-2008 05:43 PM
Lock out due to open limit amortiz HVAC 2 03-05-2007 03:34 PM
Comfortmaker RPJII - 4 flashes - open high limit switch nisad HVAC 7 12-08-2006 11:33 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.