Had our first camping trip of the season, couple things1) when i ran the furnace the blower motor would ramp up and then slow down. what would cause this?also lights would go dim with or without furnace running

The Lights going dim could be a sign of a bad ground either at the battery or the 12 volt panel or If on battery could be a large load coming on line causing the dimming if running off batteryWhere you running off battery or on shore power?

we were hooked up to shore power, had the battery tested and the gentleman said it was border line

The propane furnace blower motor is also a 12VDC item... Sounds like alot of items are losing 12VDC for whatever reason...Roy Ken

darsben1 wrote:The Lights going dim could be a sign of a bad ground either at the battery or the 12 volt panel or If on battery could be a large load coming on line causing the dimming if running off batteryWhere you running off battery or on shore power?Yes, #1 check all your battery connections for clean and secure. DON'T forget where the ground wire connects to the frame.If battery is in good shape, and ground connections are solid, likely your converter/charger is going bad. If it is WFCO, most likely going bad, replace with a Progressive Dynamics unit of the same or slightly larger size and be done with it.

rv furnace blower motor | Good Sam Community

19 Replies

Dave_H_M
Explorer II
Mar 27, 2017
thanks for posting back.
machunt
Explorer
Mar 27, 2017
replaced converter, appears to be the fix. just wouldnt handle a load.
larry_barnhart
Explorer
Mar 21, 2017
machunt wrote:
we were hooked up to shore power, had the battery tested and the gentleman said it was border line

I would buy a new battery. Furnace runs off the 12 volt. I had this issue years ago.

chevman
machunt
Explorer
Mar 20, 2017
TDS.
i already purchased a new battery, go back and check.
tdsxt51
Explorer
Mar 19, 2017
machunt wrote:
we were hooked up to shore power, had the battery tested and the gentleman said it was border line

There you go. He told what it was. Get a new battery!

Sorry- I've a bad habit of replying without reading the whole thread. Please let us know what happened when you took it in for service. Thanks.
machunt
Explorer
Mar 17, 2017
Problem not solved. lost all 12 volts the other night. i pulled the converter and checked for 13.5 volts all good. took battery and had it checked all good. talked to a service tech and he suggested check voltage at the leads to the battery without connected i did 13 volts. so we turned things on inside and lost 13 volts at the leads when fridge was turned on 120 volts. so i swolled my pride and took it in for service.
CavemanCharlie
Explorer III
Mar 13, 2017
machunt wrote:
replaced battery things seem ok, will know moew in a week when we use it again.

Thanks for posting that you think you have solved the problem. Let us moew when you are sure. :p
machunt
Explorer
Mar 11, 2017
replaced battery things seem ok, will know moew in a week when we use it again.
Old-Biscuit
Explorer III
Mar 10, 2017
When on shore power converter handles 12V DC system demands and charges battery

You have a bad battery so replace it

While you have battery removed...check Converter DC output. Should be 13.3V DC MINIMUM.
If lower or the output fluctuates then converter is also going bad.
westend
Explorer
Mar 10, 2017
Dimming lights and 12V motors running slow indicate a lack of 12V power. I'd suggest to break out a hand-held meter and check out your 12V system.

It sometimes happens that a very discharged or failed battery will put enough load on the system that a fuse will blow or a circuit breaker interrupt. After that, you will only have what's left in the battery for power.