Raypak 130A Ignites and then shuts off.

[Mikris]

Hi all,

New to this forum and have a Raypak 130A heater that has just started acting up on us. It intermittently won't stay running.
It will spark and open the valve and ignite the burner but then within seconds you hear the valve close and of course the flame goes out.
It mostly seems to happen on cool or damp mornings and will eventually stay running but it may take numerous restarts to do it.
Other times it starts up on the second spark cycle, which from day 1 seemed to be the norm.
I found PrivatePilot's thread pertaining to the same heater and saw in the last couple of posts the issue about gas pressure if something else in the house is using gas. I did a quick test by turning off the heater and trying it while the hot water heater was running and the pool heater started right up. Of course the pool heater had already been running for a while. I will take note in the morning if the pool heater doesn't fire right up to see if the hot water heater happens to be on.

Any other easy checks that I can do?

Thanks in advance.
Mike

 

[Patrick_B]

Welcome to TFP Mike!

I'm sorry I don't know, but we have a couple of folks who are pretty good on heater issues. One of them will likely see this and give you something to look for. Enjoy your time on the forum.

 

[Mikris]

Thanks for the welcome Patrick.

 

[danpik]

I did not take the time to look up the schematics on this one so I may be a bit off. Anyway, it sounds like a flame sensor problem. The circuitry in the electronic ignition heaters relies on a flame sensor to ensure there is combustion. If the sensor does not see/detect a flame or the electrical continuity thru the flame is not sufficient, the circuitry will shut the gas flow off after a pre-determined amount of time. Usually this is in the 5 second range.

 

[Mikris]

I did not take the time to look up the schematics on this one so I may be a bit off. Anyway, it sounds like a flame sensor problem. The circuitry in the electronic ignition heaters relies on a flame sensor to ensure there is combustion. If the sensor does not see/detect a flame or the electrical continuity thru the flame is not sufficient, the circuitry will shut the gas flow off after a pre-determined amount of time. Usually this is in the 5 second range.

When the gas flow does shut off it is in the 5 second range for sure. If the sensor sometimes doesn't sense the flame would it do anything to remove and clean the ignitor? If so what would one clean the ignitor with? Thanks for the reply.

 

[danpik]

There are two different types of igniters on electronic ignition units. One is a glow bar type that is a ceramic type of bar that glows red hot to ignite the flame. The other is a spark type that has two metal probes that a spark jumps across to ignite the flame. I am going to guess by your initial description that you have a spark type. On some spark type ignitions there can be a third probe with a small wire attached to it. That will be the sensor. It needs to be clean These can be cleaned with steel wool. Do not use sandpaper as most sandpapers contain silicones that can be deposited on the probe and insulate them

 

[ps0303]

Also, be careful on your ignitor as it is a two pronged type and like a spark plug, there is a gap between the two that has to be be set right for it to work properly. I have no clue on the correct distance between the two but since your system is lighting, it must be correct.

 

[Mikris]

Thanks for the replies. I will carefully clean the ignitor and report back.

 

[ps0303]

FYI, I had a Hayward unit today that would light and then go off. I could hear the ignitor clicking still after it lit. I took the ignitor out, cleaned it with steel wool, put it back in and it no longer worked. Had to replace the ignitor. Worked like a charm after that.

 

[danpik]

FYI, I had a Hayward unit today that would light and then go off. I could hear the ignitor clicking still after it lit. I took the ignitor out, cleaned it with steel wool, put it back in and it no longer worked. Had to replace the ignitor. Worked like a charm after that.

That is weird, The furnaces and boilers I work on all winter up here use roughly the same type of igniters and I clean them all the time...rarely have to replace them. I usually find they need to be connected tightly in the brackets and a lot of times they are loose.

 

[Mikris]

I scrubbed the ignitor trying not to move the two prongs. It lit right up after cleaning but it had been running before. At least I know that I did not change the gap.
The bad news is that this morning it would not stay lit right away. I guess I will replace the ignitor as they are inexpensive and see if that does the trick.
Thanks again for the advice.

Mike

 

[JohnInTX]

Raypak Low Nox 337A

I realize this is an old thread but while troubleshooting a neighbor's Raypak heater I got here via a google search on the problem of the heater firing up then shutting down. After verifying all of the sensors and the board, I googled and found this thread and it got me to troubleshooting the pilot. Hopefully, this post will help others that similarly land here.

In a nutshell, our problem turned out to be a partially clogged (with rust) pilot. Apparently, it flowed enough gas to light the burner but after the burner lit, the turbulence blew the weak flame away from the sensor and it shut down. It would repeat the process as long as it was calling for heat. On the first inspection, I found some flakes in the burner screen, blew them out with compressed air and it would not light at all. The compressed air managed to clog the pilot to where it would not light at all. A second inspection verified the clog. I cleared it out with a stiff wire (6" of old guitar string) and it lit right off.

Looking forward to pool school.