Hot water heater. we have an 05 3295 montana . we can get no hot water through any of our faucets

Question

we have an 05 3295 montana . we can get no hot water through any of our faucets but we do get cold water. it seems like the hot water heater is stopped up somewhere. is there a screen or strainer i need to check, like the one coming into the rv. heater is on electric setting and seems to be on and hot. Not sure what brand name so I am just putting anything until I find out.