Woodalls Open Roads Forum: General RVing Issues: Furnace Cycling - SOLUTION w/ Pictures
Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Help and Support  |  Contact

Search:   Advanced Search

Search only in General RVing Issues

Open Roads Forum  >  General RVing Issues

 > Furnace Cycling - SOLUTION w/ Pictures

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 5  
Next
bmupton

Saskatoon, SK, Canada

Full Member

Joined: 04/23/2013

View Profile


Offline
Posted: 05/27/13 03:50pm Link  |  Quote  |  Print  |  Notify Moderator

EDIT: This turned out to be an air flow issue. The solution was quite simple. The furnace has three knockouts on the back when using flexible vent duct adapted to hard in-floor ducting. Crossroads has only used two of the three ducts, so I knocked the third one out, moved the lower two so they ducted in to the floor and ducted the top one so it ducted in to a 4" adjustable vent blowing directly in to the kitchen.

Pictures:
The stock furnace access panel/cold air return:


Access panel removed:


Duct disconnected from floor:


This shows duct connected to new access panel/cold air return:


Access panel sitting on floor:


Access panel installed:


All I have left to do is seal a couple spots a bit better with duct tape and stain the new access panel I built to match the interior of the TT.

So, if you've got a Crossroads Zinger ZT33BH and are having furnace issues, this may solve them for you. Grand total for materials was $40 for the lumber, and my dealer provided all the ductwork and fittings for free (since it should have been a warranty issue, but I couldn't get them to do a service call to where my trailer is located).

Quote:


Brand new 2013 Zinger ZT33BH, and the furnace is misbehaving:

1.) Thermostat calls for heat
2.) Furnace fan starts
3.) Burner ignites
4.) Runs for ~2 minutes then stops, fan continues running
5.) burner ignites again
6.) Repeat steps 4 and 5 until:
7.) thermostat is satisfied and furnace shuts down normally

My only guess is a bad high limit or sail switch, but I'm not a furnace guy. Should still be covered by warranty, but I'd like it fixed in place instead of hauling it to dealer (I'm all set up for the season, don't really want to move).

Anyone else have/have seen this issue?


* This post was edited 06/12/13 10:45pm by bmupton *


TT: 2013 Zinger ZT33BH
TV: 1986 6.2 Diesel Chev 3/4 ton van


skipnchar

Topeka or somewhere else

Senior Member

Joined: 12/17/2003

View Profile



Posted: 05/27/13 04:14pm Link  |  Quote  |  Print  |  Notify Moderator

Where is your heat VENT compared to the thermostat. If the vent blows heated air directly on or near the thermostat it could easily cause it to short cycle that way. I have one heat vent located just inside my bathroom door and the thermostat is located just OUTSIDE that door. If I leave the bathroom door open it will short cycle so we either partially close that vent or close the bathroom door.


2011 F-150 HD Ecoboost 3.5 V6. 2550 payload, 17,100 GCVWR -
2004 F-150 HD (Traded after 80,000 towing miles)
2007 Rockwood 8314SS 34' travel trailer

US Govt survey shows three out of four people make up 75% of the total population


bmupton

Saskatoon, SK, Canada

Full Member

Joined: 04/23/2013

View Profile


Offline
Posted: 05/27/13 04:20pm Link  |  Quote  |  Print  |  Notify Moderator

here's a shot of where the registers are. I don't *think* the one in front of the island is blowing on the thermostat, but maybe it is. I'm not at the trailer again until the weekend, I'll stand next to it while it's in operation and see if I can feel it blowing there.

EDIT: Maybe the one in the bathroom is heating up the paper-thin wall between the bathroom and thermostat and triggering it that way. I'll test for heat there as well. I'll grab a thermometer and stick it there and see what happens.



smkettner

Southern California

Senior Member

Joined: 03/21/2005

View Profile



Good Sam RV Club Member


Posted: 05/27/13 04:21pm Link  |  Quote  |  Print  |  Notify Moderator

Besides heat blowing direct on the thermostat... also check for air flow restrictions that could trigger the high limit switch. Mine had collapsed and poorly aligned ducting when originally built and the burner would cycle every one to three minutes.


2001 F150 SuperCrew
2006 Keystone Springdale 249FWBHLS
675 watts solar
Send a PM if I missed something

bmupton

Saskatoon, SK, Canada

Full Member

Joined: 04/23/2013

View Profile


Offline
Posted: 05/27/13 04:25pm Link  |  Quote  |  Print  |  Notify Moderator

smkettner wrote:

Besides heat blowing direct on the thermostat... also check for air flow restrictions that could trigger the high limit switch. Mine had collapsed and poorly aligned ducting when originally built and the burner would cycle every one to three minutes.


I'll take a look. The furnace is under the pantry, and I'm not sure where the access is (I think there are four screws and that panel comes off, I'll have to see). The vents appear to have decent air flow out of them, but you never know.

wanderingbob

monticeeo, fla

Senior Member

Joined: 07/26/2012

View Profile


Offline
Posted: 05/27/13 04:46pm Link  |  Quote  |  Print  |  Notify Moderator

This is May , you do not need any furnace !!

five'er

Canada

Senior Member

Joined: 09/25/2006

View Profile



Posted: 05/27/13 04:50pm Link  |  Quote  |  Print  |  Notify Moderator

I recently tore my furnace apart (every piece) sorry to say but it's pretty much required to get to anything.. blower would start, It would spark but not ignite three times then shut down. I knew at that moment it was either orifice or bad valve. I cleaned it all up (Full of fine rust) and re-assembled and it fired right up, better than new. Based on your problem description I have the following thoughts.. It's an intimidating task but when you're cold.. you do what you need to do.

Blower is coming on and there is ignition.. I assume you can hear the fires burning.. I don't believe (I may be wrong) that it will light unless it's passed the sail switch stage (Which is located inside the blower/fan assembly on mine). So I'm saying sail switch is out.. High limit switch.. I'm not sure.. I'd say not likely.. My educated guess.. flame sensor? I believe the flame sensor is also the igniter. Clean it with some sand paper if it's not working correctly.. The other thing to check first would be that nothing has obstructed your in and outtakes.. Again, a semi-educated guess.. The other thing you can and should do is reseat the connection on the control board. OR.. Just wait for the service guy..

downtheroad

Pacific Northwest

Senior Member

Joined: 02/18/2003

View Profile



Posted: 05/27/13 04:53pm Link  |  Quote  |  Print  |  Notify Moderator

I agree with Skip above
Close the bathroom door.

Or like you said, "Maybe the one in the bathroom is heating up the paper-thin wall between the bathroom and thermostat and triggering it that way."

You can isolate the thermostat.

It can't be the sail switch if the furnace ignites at all.


"If we couldn't laugh we would all go insane."
GMC Duramax LBZ
Komfort
Reese Dual Cam HP
Our Rig Picture...CLICK HERE



five'er

Canada

Senior Member

Joined: 09/25/2006

View Profile



Posted: 05/27/13 04:55pm Link  |  Quote  |  Print  |  Notify Moderator

skipnchar wrote:

Where is your heat VENT compared to the thermostat. If the vent blows heated air directly on or near the thermostat it could easily cause it to short cycle that way. I have one heat vent located just inside my bathroom door and the thermostat is located just OUTSIDE that door. If I leave the bathroom door open it will short cycle so we either partially close that vent or close the bathroom door.


If this were the case would it not register the set temp on the thermostat though? as in.. the thermostat would show 72 (if set for 72) and no longer call for heat.. technically working as it should.

bmupton

Saskatoon, SK, Canada

Full Member

Joined: 04/23/2013

View Profile


Offline
Posted: 05/27/13 05:03pm Link  |  Quote  |  Print  |  Notify Moderator

wanderingbob wrote:

This is May , you do not need any furnace !!


It was hovering around 10 degrees C Friday night...If it were just me and the wife we could have generated our own heat ;-). The baby boy and 4 and 7 year olds were complaining about the cold...

five'er wrote:

I recently tore my furnace apart (every piece) sorry to say but it's pretty much required to get to anything.. blower would start, It would spark but not ignite three times then shut down. I knew at that moment it was either orifice or bad valve. I cleaned it all up (Full of fine rust) and re-assembled and it fired right up, better than new. Based on your problem description I have the following thoughts.. It's an intimidating task but when you're cold.. you do what you need to do.

Blower is coming on and there is ignition.. I assume you can hear the fires burning.. I don't believe (I may be wrong) that it will light unless it's passed the sail switch stage (Which is located inside the blower/fan assembly on mine). So I'm saying sail switch is out.. High limit switch.. I'm not sure.. I'd say not likely.. My educated guess.. flame sensor? I believe the flame sensor is also the igniter. Clean it with some sand paper if it's not working correctly.. The other thing to check first would be that nothing has obstructed your in and outtakes.. Again, a semi-educated guess.. The other thing you can and should do is reseat the connection on the control board. OR.. Just wait for the service guy..


Yep, I can hear it running. It doesn't appear (based solely on air flow from vents/exhaust) that anything is restricted. And while it's blowing, the air coming out is nice and warm like you'd expect. Just that the burner cycles while in operation.

downtheroad wrote:

I agree with Skip above
Close the bathroom door.

Or like you said, "Maybe the one in the bathroom is heating up the paper-thin wall between the bathroom and thermostat and triggering it that way."

You can isolate the thermostat.

It can't be the sail switch if the furnace ignites at all.


I'll take a closer look when we head out on the weekend. Forecast is for warm weather now though, so testing this out will be a real pain! Have to crank it up to 30 to test.

Thank you everyone for the ideas. If I still have trouble I'll get the service guy involved for sure.

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 5  
Next

Open Roads Forum  >  General RVing Issues

 > Furnace Cycling - SOLUTION w/ Pictures
Search:   Advanced Search

Search only in General RVing Issues


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:

© 2014 Woodalls | Terms & Conditions | PRIVACY POLICY | YOUR PRIVACY RIGHTS