Charging house battery

Battery voltage readings may be misleading. The condition/age of the battery, cleanliness/continuity of battery cable connections, and amount of loads on battery, if any, can affect voltage readings. I should have stated that a new/good house battery, when fully charged by, and still connected to the converter/charger, with no load on the battery from interior lights, 12 volt DC powered appliance controls, alarms and other devices, should read around 13.6 volts. When converter/charger is not connected to 120 volt AC power for some time, and engine is not running, house battery voltage should read around 12.7 volts after surface charge diminishes. When RV engine is running, it's alternator will charge the house battery, and starting battery, and both will read around 14 volts with no loads, after alternator has fully charged the battery and engine is still running. When engine is shut off, both battery's surface charge will diminish and voltage reading will gradually drop to around 12.7 volts. A new/good house battery and the engine starting battery, will gradually self-discharge to around 12 volts, even with no loads, when RV is parked disconnected from 120 volt AC power and engine is not run for a number of weeks. If you install a Trik-L-Start device or if RV is equipped with a BIRD device, the starting battery will be kept charged when the RV is connected to 120 vac shore power. At least the above is how I understand it.