Power goes out when water heater igniter kicks in for propane

[dorfmanzz]

I have a 1997 Beaver Monterey. Periodically when my water heater kicks in for the propane sometimes I lose my AC power temporarily and sometimes permanently to my coach. Any ideas of what could be causing this? When it goes out permanently it pops my fuse on my inverter and a half to reset. It is driving me crazy. Thanks for your help in advance.

[Unplanned Tourist]

Do you have an electric element that kicks in at the same time? That could do it.

[Old-Biscuit]

Propane is all 12V DC ....fed from FUSED circuit

DC demand should have NO affect on AC power.

Electric element would......check if it is being activated. It is fed from individual AC circuit breaker

No common connections between AC & DC on that year model water heater. Completely separate circuits/functions/controls

[Gary RVRoamer]

There is one remote possibility here. The inverter is also the converter/charger and is producing the 12v as well as supplying 120v to the outlets. When the igniter sparks it could cause a momentary jump in the DC amp output, thereby placing a greater demand on the inverter/charger and maybe enough to trip its internal breaker. The breaker protects the total 120vac power that the inverter/charger uses, not just the 120v output.

For example, if the other demands in the coach are running at about 18 amps and the breaker is rated at 20A, an increase of 2+ amps from the charger could push it over the breaker limit.

[Old-Biscuit]

Inverter......
Takes 12V DC and produces 120V AC
Can also be a 'charger' for battery

Converter....
Takes 120V AC and produces 12V DC
Can also be a 'charger' for battery


When water heater (or furnace or fridge) spark electrode fires it is only using 12V DC as source..........a transformer increases the DC voltage for the actual spark---but 12V DC is still the source. Spark electrode does not place a large demand on 12V System because of transformer

OPs 120AC issue is an overload on 120V AC supplied by inverter.....as evidenced by inverter AC breaker tripping.

Either an 'unknown' AC demand is occurring (water heater element??)
OR
Inverter is failing......can't supply AC System AND provide charging demands for battery (DC System)

Need to test/measure Inverter performance.
Would need Inverter Brand/Model to obtain 'service manual' for Inverter specs
(It is 20 yrs old)

[dorfmanzz]

That's what is happening to me. Old Freedom 20 inverter/ charger. Probably time for a new one. Can not find parts anymore.