Unit Will Not Power On - Rheem RTG2-42 Troubleshooting Manual

Unit Will Not Power On

Explanation: Nothing happens when water is flowing through unit. At a minimum check the
following in all cases:
1. Make sure unit is connected to proper 3 prong, grounded power supply and circuit
breakers are on.
2. Clean cold inlet water supply filter. Ensure you have at least the minimum flow rate
required to fire unit. Turn on several fixtures to make sure.
3. On new installations ensure hot and cold water lines are not crossed. Make sure the unit
is plumbed cold in to cold inlet. Unit will not fire off if water is running backwards.
Is the power
cord plugged
in? Is the
hardwiring
connected?
Yes
Is there
voltage at the
wall plug?
Yes
Will the unit
go into
Maintenance
Mode?
No
No
Plug unit into a grounded, 3
prong wall plug. Verify hard
wire to unit if applicable.
Verify breaker at service panel
is not tripped.
No Check voltage at wall plug and circuit breaker for
acceptable levels. Repair as required. This is not
a water heater issue. This is an electrical issue.
Yes
Go to 1Y and verify zero flow rate. If there is
ANY flow rate at 1Y; the unit will not power on.
To access the Maintenance Display, turn the unit OFF. Then hold
down the UP and DOWN arrow keys at the same time for a few
seconds. You will hear an audible beep and see the display go to 0E.
By pressing the UP and DOWN arrow keys on the remote display, you
can access a variety of information about the machine.
SVC 810 Tankless Troubleshooting Manual
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