Furnace & Lights

[Eborges]

Anyone have an idea on why when my furnace comes on, the lights flicker. I'm not sure what it can be, since it doesn't happen every time. Any suggestions, will be greatly appreciated.

2009 Crossroads RV Cruiser 30SK 5th wheel.

Edson

[Wingerdinger]

It could be a number of things. the first thing I would check is your battery and it's state of charge.
I believe every RV owner should have a multimeter, and know how to use it to test the health of their 12 volt charger/convertor/battery systems.
First, while on shore power, check voltage across your battery terminals, it should be in the 13 volt range with your battery charged.
After charging for a day, unplug your shore power, wait 1/2 hour, and check the battery voltage. It should be 12.6+ volts if your battery is fully charged and in good condition.

[660catman]

Voltage is one thing but load test it too. I’ve had batteries show good voltage but fail the load test.

[dagst1]

When the lights"flicker" are on 110 - plugged in - or just battery -12volt?

[Eborges]

110!

[dagst1]

Can't say definitely if this is your problem but this was what we encountered.
It started with the lights and furnace on at the same time. We would not notice the lights dimming down but all of the sudden they would get bright or just back to normal brightness. Then later in the year it started to do the same thing with the air on. Then also with the air off. Now the air is 110 so it should not affect the 12 volt lights. The end result was when the battery started to loose charge.

That was when after some checking with my multi meter i determined that the converter was on its last leg. Replaced the converter and all was good. Also took this opportunity to see where all the wires went - what fuse to what light or appliance and what breaker to what outlet - then labeled the new converter accordingly.

As i stated not sure if this is your answer but it was mine.

[cwalther1]

I would say either weak batteries or bad converter. Mine was both. Try turning on all lights and see if you have flicker. Does it do it while A/C is running or just furnace ?

[MartyinSC]

I agree with cwalther1. It seems like you have a flicker when there's a load on either the 12V side or the 120V side. I'll bet it's the converter, or a battery that is not dampening the load. (you're not running with the battery cut off, are you? That would do it for sure). Finally, flickers can come from poor connections.