Raypak Conversion Professional series Propane to Natural gas

gatorson

Member
Sep 18, 2018
16
Fort Lauderdale
OK Guys, I have an interesting situation. I currently have a 15 yr old Raypak 406a P-M406A-EN-C natural gas that needs replacement; it fires up properly but the firewall is so old it overheats. Here's the situation - I've found a professional series 409a that is propane B-R409A-EP-X. Would I be able to swap out my existing NG orifices and NG gas valve regulator onto the professional series propane version? Are these the only items that would need to be changed for a conversion or is there more to it?

Thanks.
 
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Pool Clown

In The Industry
Sep 5, 2008
2,152
Silicon Valley, CA
In theory, yes. The gas valve would, or should be 3/4 thread so that's no problem. If you have already taken delivery of the new heater, you can take a jet out of it and see if they are the same thread, also, should be. That just leaves the board. The board on the propane, depending on the age, will have a tab that has been broken off. This isn't the end of the world, it'll just make for an aggravating start...

Propane is heavier than NG when its in gas form and it likes to sink to the floor and pool, making for some lively outcomes if it happens to pool in the right place. The designers at Raypak found a way around this. When the tab is broken off, the system will only try to light one time before it locks out, instead of the three tries for NG. At which time you will need to disconnect power from the heater to reset it and then try again.
 

gatorson

Member
Sep 18, 2018
16
Fort Lauderdale
In theory, yes. The gas valve would, or should be 3/4 thread so that's no problem. If you have already taken delivery of the new heater, you can take a jet out of it and see if they are the same thread, also, should be. That just leaves the board. The board on the propane, depending on the age, will have a tab that has been broken off. This isn't the end of the world, it'll just make for an aggravating start...

Propane is heavier than NG when its in gas form and it likes to sink to the floor and pool, making for some lively outcomes if it happens to pool in the right place. The designers at Raypak found a way around this. When the tab is broken off, the system will only try to light one time before it locks out, instead of the three tries for NG. At which time you will need to disconnect power from the heater to reset it and then try again.
Thanks - I forgot about the board tab - I'm assuming I could also move over my NG board from my current Raypak as well? Is there any other way to replace/short the broken tab, I think it would be aggravating to have the heater continuously locking out after only one attempt at lighting. My current raypak usually doesn't fire up on the first attempt, so I'm not sure the propane board would ever fire up on the first try.
 

Pool Clown

In The Industry
Sep 5, 2008
2,152
Silicon Valley, CA
There may be an issue with the heater that wont fire on the first attempt. IOW, that may not be a board issue, but yea, if the harness plugs look the same, it should work. Several years ago, Raypak made the board connections "idiot proof" by making all the plugs all different sizes. They will connect only one way, and in only one location.
 

gatorson

Member
Sep 18, 2018
16
Fort Lauderdale
There may be an issue with the heater that wont fire on the first attempt. IOW, that may not be a board issue, but yea, if the harness plugs look the same, it should work. Several years ago, Raypak made the board connections "idiot proof" by making all the plugs all different sizes. They will connect only one way, and in only one location.
I've done a little more research and it seems that this model of professional series uses a fan blower. I was looking at the schematics here and it shows that there is only 1 gas valve orifice for either propane vs NG. Is this similar to other blower style heaters where just this 1 orifice needs to be changed? The part number for the gas valve is the same for both propane and NG so I'm assuming it is adjustable for either gas. I understand that the board may have the propane tabs broken off but otherwise I would think it would still fire up with this new NG orifice here.
 
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ps0303

TFP Expert
In The Industry
Jul 6, 2011
4,049
FL
Is this professional series heater like really really cheap as to why you are considering it? Yes on their board if it is a propane unit there is a tab that is broken off of it to change the timing of opening of the gas valve.
 

gatorson

Member
Sep 18, 2018
16
Fort Lauderdale
Is this professional series heater like really really cheap as to why you are considering it? Yes on their board if it is a propane unit there is a tab that is broken off of it to change the timing of opening of the gas valve.
Yes, it is pretty cheap ~$500. From the replies it seems like it may be more of a hassle than it's worth. I've also reached out to a Raypak rep and he said the igniter/orifice would obviously also need to be replaced and it is in a very tricky location to do so. Thanks for all the feedback and I will continue my search for a more suitable Raypak. If anyone has any good leads in the south Florida region please feel free to DM me. Thanks.
 

RichTJ99

Gold Supporter
Sep 16, 2016
232
Katonah NY
Hi - sorry to jump into this thread but my Raypak 406 is having this exact issue - starts once, then locks out. I do see a flame so i am a bit confused.

I pulled the stack apart (it lives indoors) to clean and it worked fine for a short time. The other day I turned it on and it felt like it was overheating, the Lcd panel was almost unreadable so i shut the system down to see what was up & when i tried again I get the lockout after one start (though it seems to start OK).

Where would I find the tabs - on the control panel board?

In theory, yes. The gas valve would, or should be 3/4 thread so that's no problem. If you have already taken delivery of the new heater, you can take a jet out of it and see if they are the same thread, also, should be. That just leaves the board. The board on the propane, depending on the age, will have a tab that has been broken off. This isn't the end of the world, it'll just make for an aggravating start...

Propane is heavier than NG when its in gas form and it likes to sink to the floor and pool, making for some lively outcomes if it happens to pool in the right place. The designers at Raypak found a way around this. When the tab is broken off, the system will only try to light one time before it locks out, instead of the three tries for NG. At which time you will need to disconnect power from the heater to reset it and then try again.
 

Pool Clown

In The Industry
Sep 5, 2008
2,152
Silicon Valley, CA
Where would I find the tabs - on the control panel board?
Yes, should be labeled. However, if the heater once (upon a time) ran fine, then you shouldn't need to fiddle with them. Look for a sooted exchanger, if you think it's overheating.

You mentioned that the heater lives indoors. If there isn't enough fresh air getting to the heater for combustion as well as make up air, you could be experiencing the effects of a sooted up exchanger. This is something that doesn't develop overnight. It can take months, even years to develop. It depends on how often and long the heater runs with an air deficit.

Raypak's are particularly forgiving to this condition, but it doesn't mean that they cannot succumb to getting sooted, it just means that it will take longer to develop.
 
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RichTJ99

Gold Supporter
Sep 16, 2016
232
Katonah NY
I had someone at my place today. He took it apart & said the burners need to be replaced- i have 22 - he said i have a Raypak 336 not 406. He also said my heat exchanger is slightly leaking & I should replace that too.

He is going to get me a price on those parts.