Hot water issues on our 2014 Phaeton 36GH

[ColonelB]

First of all, love the new MH. It's amazing. We've had it since September so we have a short laundry list of warranty issues that are in the process of being handled. Our biggest issue now is the hot water. We have a Precision Temp Model 500 instant water heater. When we are using the coach's water pump we get hot water almost immediately in all faucets including the shower. However, when we are connected to city water the burners don't all fire off. Hubby and I are trying to troubleshoot before we take the rig to the dealer for attention. We firmly believe that the water heater is operating properly and think the problem is a restricted water flow somewhere in the coach (restriction or obstruction?). We unscrewed the flow restrictor valve from our hose and experienced the same result. So the problem, as we see it, is not external.
Has anybody had this problem? Any ideas that we could pass along to the technician to reduce the amount of head-scratching time? I want to go camping and have a hot shower in the morning!

[trackman]

There should be a switch to go from water pump to city water. Look at the base of the hot water heater and the bin for the city water connection

[Grn_Mtn_Boy]

Make sure you have the water valve in the "city-water" position.