Raypak Flame Rollout around pilot

[mack81]

Hello all!

I am getting flame rollout from around the ignitor on my Raypak.

I have taken apart everything and thoroughly cleaned it, I have checked connections on the ignitor components and I am still getting visible flame rollout from the ignitor area.

From the picture you can see where they are rolling out.

Any suggestions about what I can try? Could it be a fault with the ignitor? a hole or something maybe?

 

[swamprat69]

It looks as if you have multiple areas of concern ( bottom right and midlevel front ). Aphoto of the entire front of the exposed heater would be helpful.

 

[mack81]

Thanks for replying, here is a few more pictures.

I was having some issues towards the end of last season and removed the burner tray and cleaned every row so I am confident there is no blockage there. Having put everything back and ran the heater I can see flames coming up from around the pilot.

 

[swamprat69]

Flame rollout is indicative of a blockage to the flow of combustion byproducts. What condition were the burners in when you cleaned them? Was there significant debris on top of the burners and in the burner slots? It looks like you have been producing soot on the right side by the pilot assembly. It looks like rollout has occured from the right side to slightly past the middle as indicated by deterioration on the bottom of the combustion chamber front plate. Also discoloration on left side below the rollout switch and rusting of left hand burner tray mounting brace indicate a problem in that area. Discloration on operating instruction tag can be from rollout or possibly deterioration of combustion chamber insulation. Sooting is caused by incomplete combustion of the gas/air mixture resulting in a yellow flame that is not strong and well defined. A normal flame is strong and well defined with a two toned blue inner and outer cone. You should observe the burner and pilot flames while the heater is running to see if it conforms to a normal flame and is equal across the burners. When you had the burners out you should have inspected the combustion chamber and heat exchanger for blockages (soot or deteriorated insulation that fell out of place ) and deterioration of combustion chamber insulation from both the top and the bottom. I would advise you to performs these extra steps at this time.

 

[mack81]

Thank you for the detailed advice.
The burner tray did not seem particularly dirty or blocked when I had it out, but I have nothing to compare it to. The heat exchanger was probably worse, it had a lot of leaves and debris on it at the time too. I have cleaned both thoroughly.

From what I can see when running the burner flames look ok (a lot of yellow/orange but uniform and with blue cones at the bottom), but around the pilot it is not, no blue cone, random orange flames licking around it from both sides.

I did not know to look for/at insulation, I will do that next.

As you point out there seems to be a lot of soot, I am hoping that much of those other areas were the result of blocked burners and/or heat exchanger and now that I have cleaned them and the flame looks ok that the pilot is the remaining problem where the flame is poor. I have ordered a new pilot to see if that helps.

Thanks again!

 

[ajw22]

Yellow and orange flame color is not good.

Have you checked your static and dynamic gas pressures using a manometer?

 

[mack81]

I have not, I have never used one.

Again, I am not sure what things are supposed to look like, but here are some videos I took, to me the left side (first video) looks like it's running well, mostly a blue flame (to me), and the right side around the pilot looks wrong (2nd video), which is why I am thinking something to do with the pilot is my issue.

Main Burners

Left Side - Main Burners.MOV

drive.google.com

Pilot

Right Side - Pilot.MOV

drive.google.com

 

[swamprat69]

The yellow at the pilot is probably due to dirt rerstricting the pilot orifice and a new pilot assembly should correct that. For the heater to run properly it is imperative that there should be no restriction of the flow through the heat exchanger. You can remove the burner tray and put a work light under the heat exchanger and look down from above to check for any blockage through the heat exchanger fins. You should also check/clean the gas manifold orifices for restrictions from spider webs which can effect the flame pattern. Be sure to check for gas leaks after replacing the pilot assembly and be careful not to overtorque the brass compression nuts on the pilot tubing as they tend to round off easily.

 

[wireform]

+1 As @ajw22 said above. The manometer check would be my #1. Is there a drip leg on the gas line, perhaps dirt in the gas valve. I just last Friday ripped out a burner tray which was completely rusted and caused a roll-out error. Installed a new complete assembly and it's working well but it needed a major clean out top to bottom. Make sure the heat exchanger is completely clear between the fins so there's proper updraft for combustion. This is a picture from after the new install looking through a small opening in the most right side.

 

[swamprat69]

Just saw the videos. The whole burner flame should look like the flame does at the far end of the burner (defined two tone blue flame). Not sure from videos exactly what the main portion of the burner flame looks like.

 

[mack81]

Hi Again all,
So here is where I am,
1. I took everything out again and triple checked it was clean - burner tray is perfect, heat exchanger is perfect, no insulation damage.
2. I replaced the pilot assembly as well as the pilot gas tube (I noticed the new one is much narrower than the old one, so I thought maybe a lesser flow would help.

The main burners are running perfect, defined blue flame across every row.
However, I am still getting flame rollout from the pilot assembly. (Should the pilot remain flowing once the main burners are lit?)
See the video of the new pilot assembly in action, you can see it is continuously surrounded by flame and after a couple of minutes this flame start creeping back towards the opening and up around the area where you can see the black soot on the unit.

New Pilot Assembly.MOV

drive.google.com

Any ideas what I can do next?

Thanks again for all the advice!

 

[ajw22]

Show us pics of the heater location.

A backdraft could be causing the flame rollout. You may need a flue extension.

 

[mack81]

Here are the pics.
I would have thought any environmental factors would impact the whole tray, not just the pilot.
What's baffling me is how it is just the pilot surrounded by flames - connections are good, new one and old one behave the same.

 

[ajw22]

I would trim back the branches that have grown over the heater.

 

[1poolman1]

Here are the pics.
I would have thought any environmental factors would impact the whole tray, not just the pilot.
What's baffling me is how it is just the pilot surrounded by flames - connections are good, new one and old one behave the same.

A big part of the problem could be those trees surrounding the pool equipment. The overgrowth and surrounding trees won't allow the heater to vent properly and you will get flame rollout with even the slightest breeze and maybe all the time. The RayPak 009836 outdoor stack kit might be the answer as it is designed for an installation like yours.

 

[mack81]

Really? wow, I had no idea. I had heard of people having issues with pool equipment too close to things but I didn't think mine was really that close, I can walk around it. You think that the overhanging trees could be causing my issue?

What does the stack do? Looks like it goes on top and could potentially be more affected by the trees no?

I can cut them back, is the overhanging the issue, the heater needs space straight up?
Thanks!

 

[1poolman1]

Really? wow, I had no idea. I had heard of people having issues with pool equipment too close to things but I didn't think mine was really that close, I can walk around it. You think that the overhanging trees could be causing my issue?

What does the stack do? Looks like it goes on top and could potentially be more affected by the trees no?

I can cut them back, is the overhanging the issue, the heater needs space straight up?
Thanks!

It really doesn't make a lot of difference how high they are trimmed, its the fact that there is, essentially, a high wall very close to the heater. In this case a wall of trees. I've had heater installs where the heater was at least 10' from a two-story house that needed the stack. Shouldn't have, but it solved the problem that was just like yours, flame rollout.
If you look at the picture of one you will see that it isn't just an 8" pipe, but there is a skirt near the top that will cause an air current to rise and help carry the exhaust out. The design also mitigates any "downdraft" that can occur when even a slight breeze hits that wall of trees.

 

[mack81]

Manometer arrived - checked the pressure, looks good, fluctuating around 3.4-3.5.

If it was an environment issue wouldn't I expect it to occur before now? The heater worked fine for 3 years. Also, wouldn't there be certain conditions that would potentially not cause the issue? I 'd rather not spend $300 on a stack if it's not going to resolve the issue.

 

[ajw22]

If it was an environment issue wouldn't I expect it to occur before now? The heater worked fine for 3 years. Also, wouldn't there be certain conditions that would potentially not cause the issue? I 'd rather not spend $300 on a stack if it's not going to resolve the issue.

You think your outside environment is static?

You can spend $300 on the stack or cut down all the tress around it.

You are not going to get the heater running by staring at it.

 

[1poolman1]

Manometer arrived - checked the pressure, looks good, fluctuating around 3.4-3.5.

If it was an environment issue wouldn't I expect it to occur before now? The heater worked fine for 3 years. Also, wouldn't there be certain conditions that would potentially not cause the issue? I 'd rather not spend $300 on a stack if it's not going to resolve the issue.

For 32 of my last 35 years, when I became an installation and repair service only, I have heard something similar, "It was working yesterday." "Last season was fine." My reply is usually, "I'm sorry, but it isn't working today." If you ever had a flat tire you know that it was round yesterday.
The heater is not the same one that has been working for the last three years. They slowly "cook" themselves into oblivion, can't be helped.
It may, in fact, have damage in the combustion chamber that is causing the rollout problem. You can remove the burner tray and examine it to tell. If that is the case, you would have been happier with a $300 stack.
However, the most common problem is what is seen in the pictures, a downdraft and improper ventilation because of the tall surrounding vegetation, which must have grown more dense in the last three years. Best guess from 30+ years going to heater schools, working on those heaters, and 2000 miles away.