Hayward H300 won't power on

[Orion18]

I have a Hayward H300ED2 electronic ignition heater I am having some issues with. I just replaced the front header due to a crack. When I turned it on after replacing the header there was a small leak by the header bolts but it fired right off and was heating. I took the header off again and had pinched the o-ring which is why I had the small leak. After tightening everything back down, I turned it on and my leak was gone, but I was getting the clicking noise for a few seconds but it would not light off.
i tried it several times and finally my display went blank and it seems like there is no power to the unit. It looks like the E fuse on the control module is blown. What would cause this fuse to blow?
What should I try next? I was thinking the ignitor might be bad, but now that the fuse blew I'm unsure how to proceed.

 

[Patrick_B]

Nor am I Orion, but I wanted to welcome you to TFP.

I'll see if I can get some help your way. Enjoy the forum.

 

[satpoolman]

If I remember correctly, there is a wiring harness for the electronic ignition that runs near the header where you were working. Look to make sure you didn't accidentally pinch one of the wires, that would definitely cause the fuse to blow.

That clicking you heard was the ignitor sparking. Make sure the gas supply is "on" then check the burner orifices for clogs/spider webs...pipe cleaners work nicely.

Just some areas to check for starters, hope this helps.

Regards,
E

 

[ps0303]

If the control board got wet from any water spraying on it, yes that would cause issues. Not sure where the leak was and if it was spraying any water on the board or not. Use a volt meter to check that you have the correct power in coming to the unit and then check on the heater side of the transformer to make sure you have 24V going to the board. After you check that try replacing the fuse and see what happens.

 

[Orion18]

Well I tried a couple more fuses and they instantly blow. Hayward told me to check to see if there was 24 volts on the yellow transformer wire and if there was voltage it was the control board.
Just got done checking and I'm showing no voltage on the yellow wire running from the transformer to the board.
Anyone know what this could mean?

 

[ps0303]

Yes you should have 24v coming from the transformer to the board.

Is you heater wired for 120 or 240?

 

[Orion18]

240
I am getting around 27v coming off of the grayish white wire on the transformer to the board. The wire right next to the yellow one on the left side of transformer. Could this be a transformer problem? Just can't figure out why it keeps blowing 3 amp fuse

 

[Orion18]

Sorry it's 120 my mistake.

 

[Orion18]

Ok.....I unhooked every wire and plug and checked connections throughout the entire heater. After I reconnected everything the fuse finally held
Now when I power it up the display shows


It then lights for a few seconds and I get the SF code. The thermistor is brand new because I just replaced header.
I think I messed up the connection point on the board, it is now loose and wobbly.

My questions are:
1. What does the 05 mean on the display?
2. Is there anyway to fix the sensor port on the board? Or do I need to buy a whole new control board?
3. Is there a part number for JUST the circuit board without buying ENTIRE bezel assembly and keypad?

 

[ps0303]

Are you sure all of the lines on the display work? It wouldn't be a 05 for an error code but could be an 85 for the temp.

You should be able to re-solder the port onto the board.

Hayward doesn't sell the board separate from the bezel fro this model. So when you end up buying the entire piece.