Restricted Hot Water Flow/City Water Check Valve

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I have , what appears to be two separate problems with my Water System.  I have a 2007 Monaco Diplomat with a six gallon Atwood Water Heater.  My City Water Hose is Reel Mounted.

My two problems are: (1) the City Water Check Valve is not operating and (2) my hot water flow is less than half the flow of the cold water flow at all faucets. 

With respect to the City Water Check Valve, the water flows out my City Water Hose when running the pump.  I can work around this quite easily by putting a cap on the end of the Hose when I store it.  I know where the 'check valve is when there is no Hose Reel and I will appreciate anyone telling me where it is usually found when you have a Hose Reel.  I would like to have some idea before I remove the plastic wall in the Water Bay.

With respect to the water flow, I know it is the Water Heater as I get equal flow, hot/cold, when I bypass the  WH.
Have not removed the Water Heater, but I realize that it is probably a defective check valve.  My question is, does the Atwood WH come with an attached Check Valve on Coldwater Side as I see a large galvanized nipple on the CW input.  The Check Valve for the HW outlet is rather obvious as it is brass and obviously added during installation.

Any input will be appreciated.

The water heater check valve set-up depends on the design of the bypass system. A single lever bypass will have check valves at both the cold inlet and hot outlet, while 2 or 3 lever bypass system normally do not use them.  It is typically the one at the outlet that gets gummed up with salts formed in the hot water.

How does your hose reel connect to the RV water system? If it screws into a standard hose thread inlet, the check valve will normally be part of that inlet. If it has some other, more permanent connection, then a check valve is usually placed inline in that connection.
Havedoe a bit more research:

1.  Mine is a single lever bypass in that it either connects the Cold Water In to the Cold Water input to the Water Heater in Normal position or it connects the Cold Water in to the Hot Water Output in Bypass position so the Check Valve is between the Water Heater Tank and the Bypass Valve. Doubtful ther is a Check Valve on Cold Water Input as it is disconnected from watersource during Bypass.

2. According to Atwood the fitting on the Cold Water Input is merely an extender.
The Hot Water Flow was getting worse (heaven forbid if it failed while Wife is taking a shower)  so I took the Bypass Valve and Check Valve off the Hot Water Output on the Water Heater.  The Check Valve was broken,  I had purchased a brass spring loaded Check Valve but it was physically to long even though it had the right threads.

I removed all the parts of old Check Valve so I had a straight thru pipe and put it back in.  With the Bypass Valve engaged the Water Heater will fill thru the Ho****er Outlet.  If I can find the correct Check Valve I will replace it but, since I use the I-95 South Winterizing method,  am in no hurry.

Was able to do the above without pulling the Water Heater out of the MH.  Did have to cut the PEX line between the Bypass Valve and the Cold Water Input of the Water Heater, thank God for Shark Bite In-line Connectors.

I will next work up the energy to pull the Plastic Panel out of the Water Bay and replace my faulty City Water Check Valve.  I can't see my Hose Reel until I pull the Plastic Panel but I do have a new Brass Check Valve to adapt to the City Water In. 
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