Heater

[BodeFamily]

My Hayward H200FDN heater started throwing an IF error this morning. When it did this last year we replaced the gas valve and the flame sensor; both of those are less than a year old.

When I check the manifold pressure, it seems like it only registers gas getting through for about a second, then drops back down as though nothing is happening. For example it will hang out at 0.34 (where it is when the system is off). Then jump to 2 for about a second while it’s going through the ignition cycle, then back down to 0.34. In that moment, I can usually smell gas.

Gas pressure at the inlet is actually a little high (12; maximum in the manual says 10 maximum).

Thoughts on other things I should look at? I have the gas lines off right now since I could smell gas annd the pressure was off.

The heater is 10 years old, so I recognize it may just be time to replace/upgrade. But willing to try a few more “easy” fixes first. Just not sure it’s worth sinking much money into it.

Thanks!

 

[ajw22]

If the heat goes out within a few seconds of coming on you can have a clogged orifice, very left hand one, at the ignition and flame sense area. Spiders seem to like that orifice. Turn gas off at the external gas valve. Remove the gas pipe to the main valve, remove the 4 screws holding the manifold in place, examine all the orifices.

If you see a clog, remove the orifice (3/8" or 7/16" wrench, depending on what Hayward installed) and push the clog backward out of the orifice. If you don't remove the orifice the clog will just move to another area.

These are the easiest manifolds to remove and replace. While it is easier if you remove the wires from the main valve, you don't have to if you are careful. If you do, take a cell-phone picture first to put them back where the belong.

Be sure to use a bit of thread sealant when reassembling the gas line EXCEPT on the union. Make that very tight. Do not tighten the pipe into the main valve beyond where the old sealant shows, you can crack that valve if you overtighten. Use some soapy water to check for leaks. If not comfortable working on gas plumbing, hire a pro.

 

[BodeFamily]

Thanks. Checked that, and nothing clogging any orifices.

For what it’s worth, the heat doesn’t actually come on. It just runs through 3 cycles of trying to ignite and throws the IF error. Usually the pressure jumps for a second on its second ignition attempt.

 

[ajw22]

Clean the flame sensor.

Check the flame current.

Clean corrosion from all the grounds.

IF, ignition failure, usually means it attempted to light and the flame went out. It will try three times and then give you the IF code. Could be as simple as a bad flame sensor. On the FD units, the flame sensor is a separate sensor and sometimes you can use steel wool or a small steel/diamond file to clean it and it will work.

The flame is sensed in current (microamps or uA) in what is called DC but is really a highly dampened AC Sine wave. The AC Sine wave is dampened because of the large difference in the area of the flame sensor (small area) and the grounding area (large area).

The flame sensor should be cleaned with steel wool or a small steel/diamond file because cleaning with sandpaper or emery cloth can leave residue that will impede conductance. On the other side (ground side) all surfaces from the burner back to case ground must be clean bare metal (as the flame signal is sensed through the flame). This includes the burners and burner slots which can be cleaned with a wire brush and any other metal to metal surfaces back to case ground which may have lost conductance due to dirt/corrosion/oxidation. This would include orifices ( if the burners are hung directly on the orifices ), burner brackets and any other metal to metal breaks that occur between the burners and the case ground.

If the grounding surface is reduced through dirt/corrosion/oxidation you are reducing the difference in area between the flame sensor and ground and the current can no longer be read as DC (highly dampened AC).

If you need to check the flame current you can use a meter that will read micro amps DC by removing the flame sensor from the circuit board and placing the meter in series from the flame sensor wire to the flame sensor post on the circuit board.

 

[PoolGate]

I would suspect the ignitor.