Furnace help
I have a hydroflame 79/80 in my 1996 Lance 11.5. It worked great last year before I unlocked her for the winter. I just put it back on and off course New England is not going to let go of cold nigh...
Forum Discussion
wa8yxm wrote:
This document is generic for both furnaces and water heaters.. I'm told I missed one possible error..
NOTE: THis is for Direct Spark Ignition Furnaces. If you have a pilot light (I suspect you do not) major mods are needed.
When the T-Stat calls for heat the control board starts the blower (1)
The blower blows closing the sail switch (2)
The control board then opens the gas valve (3) and begins sparking (4.1)
Gas Flows (5) And ignitets (4.2)
The flame heats the flame sensor (5)
The flame sensor sends .480 volts to the control board (6)
which then detects the .480 and continues operation (*)
When the T-stat says "Enough already" (RV is now warm)
The control board shuts off the gas flow (*)
and then turns off the blower after a cool down (*)
*: At nearly every step the control board is involved. IF IT IS BAD, things will not work.. I recommend replacement boards from Dinosaur boards.. When Mine went out the Dino board was less than half the price and when opened the box the quality of construction and workmanship, and then design was very clear to my trained eyes.
1: No 12 volt to furnace, blower motor shot
2: Low 12 volt, air ducts clogged, blower "obstructed" bad sail switch
3: Bad solenoid, Clogged Gas Jet
4: .1: Bad ignition circuit (high voltage) on control board. .2: Points too wide (Very common it seems)
5: These do not often fail but they can
5: Bad connection, NOTE:
5 and * Bad wire.
* applies to all steps by the way So does bad wire/connection.
It appears as if the sail switch has made an early retirement.
I jumped past it today and was rewarded with an immediate spark. unfortunately I was unable to continue troubleshooting due to some personal commitments.
The problem I am having is the sail switch is in the back of the furnace and is behind an exhaust hose that is coming from the front. From what I can ascertain I need to remove the entire furnace from the camper in order to replace the switch.
Is there a way to determine which sail switch is in here without taking the old one out? Just trying to minimize the amount of downtime.
