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Rick, Construction Supervisor
Category: Plumbing
Satisfied Customers: 19080
Experience:  Licensed Master plumber with 40+ yrs. experience.
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I have a Ruud gas hot water heater with a Robertshaw gas valve

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I have a Ruud gas hot water heater with a Robertshaw gas valve #AP12556-1. I got a flashing light stating that the max ignition attempts (2 flashes) had occurred and the water heater was not firing. After turning the power off and then back on, I get a constant flashing stating to replace unit. What unit is bad? Is it the gas valve itself or just the electronics or does the entire unit need replacing? Also, no one in my area, Harrisburg PA, seems to carry Robertshaw
HiCustomerbr />
I take it this is a power vented heater. When you cycle the power off then back on nothing happens? No fan, nothing? Just a replace gas control valve error? Does anyone in your area carry Ruud?
Customer: replied 6 years ago.
Yes it is a power vented heater. Cycling the power back on does fire the water heater along with the fan. The unit has fired due to water usage since the initial shutdown yet the flashing light stating to replace the unit continues.
It sounds like the gas control valve is starting to fail, at least it's diagnostic function seems faulty already. It might be advisable to look for a replacement while it's still working assuming the heater isn't more than 7 or 8 years old. The valve will be pricey and a heater that old doesn't have to many more miles in it before it springs a leak. If you decide to replace it your best bet would be to locate a Ruud distributor nearby or call Ruud at

If your unit is less than 6 years old it may still be under warranty
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Customer: replied 6 years ago.
The unit is only 5 years old as of August.

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