Polaris PBCG gas valve replacement

gjh42

I have a 25 year old Polaris PBCG water heater (1997), 34 gallon, 100MBH propane. It has worked great for most of that time with a few ignitor replacements, but recently started failing to ignite and locking out while I was away, not good in winter when it heats the house. Now it never runs properly, always shutting off with a 3-flash error code (failure to ignite). It seemed the ICM was giving the burner only one second of opening before shutting off, so I got the correct replacement for the model (UTEC 1018-524). It now seems to give the exact startup intervals it should, but still locks out with the 3-flash error. The gas control valve for PBCG is discontinued and I have not been able to find one anywhere including ebay. Is there any gas valve that can be used to replace this model? I would hate to throw an expensive and otherwise good heater away, not to mention the hassle of installing a new one in the confined space I have.

hot_rod

How long do you think the tank itself is going to last? It’s not a matter of IF the tank will leak, but when. Sooner or later you will need to go to plan B, maybe now is the time before you dump more $! Into it?

gjh42

Being all stainless steel, I thing it has quite a few more years in it. A replacement gas valve for a couple hundred dollars is a lot easier than replacing the heater and reconfiguring all the connections in a very tight space.
Is a "universal" replacement gas valve inherently going to cause any problems? I found this one https://www.ebay.com/itm/161887422152 (36H32-214 White Rodgers Heating Furnace Electronic Ignition Gas Valve 24V) which is set for 100MBH and1/2" NPT connections, like my heater. It is straight-through rather than rear outlet as the original is; is it bad to add an elbow to make it fit between my gas supply and the blower?

Larry Weingarten

Hi @gih42 , There is an independent parts house I deal with, and they have always had answers for me when nobody else did, and they seem to be able to find nearly anything. Call Mack Stove at 831-899-7278 and ask for Dan or Mike. See if they can help. They just helped me with finding a gas valve for a forty year old commercial State water heater.

Yours, Larry
ps, I trust your water is low in chlorides?

hot_rod

I’m pretty sure the Polaris uses a negative pressure gas valve. As the blower ramps up and down it pulls the gas and blends it for the burner. That is how the burner modulates. I have never seen a universal replacement valve like that. I think you want to find an OEM valve.

Alan (California Radiant) Forbes

I believe they are made by American Water Heater Company. One of these numbers should work and if you give them the serial and model numbers, they should be able to source a gas valve for you.

(800) 456-9805
(800) 999-9515

I have a few of these on my route and they seem hang in there. The igniters seem to last longer when you turn the temperature up.

gjh42

Yes, the Polaris wants a -.02" w.c. manifold pressure. I don't see enough information on the universal replacements to know if they would accommodate that.
Thank you for the various recommendations on contacts for OEM units. I will update when I have more information.

gjh42

I have recently read that ignitors fail quickly below 140F settings; I have kept mine around 120 F, and ignitors have lasted 6-8 years on average. I have replaced it three times, most recently just a couple of years ago, and I still have another spare on hand.

HomerJSmith

Polaris had a program where they would supply parts for free to replace original faulty parts. One would get a new blower, control board, igniter and a few other things.

You might qualify, I would contact them. Supply them your model and serial #.

Alan (California Radiant) Forbes

@HomerJSmith After 25 years?

hot_rod

Numerous places sell those old Polaris parts, gas valves seem to be out of stock at all the places I looked. So either back order or no longer manufactured?

I think you can still purchase new Polaris tanks? It was a sweet radiant heat source, at a good price

One or the large online radiant suppliers sold them as combined open systems for many years.

Original purchase price divided by 25 years of high efficiency performance. It shouldn’t owe you much😙

Alan (California Radiant) Forbes

The older ones had a small, non-adjustable differential on the operating limit and they would short-cycle like crazy. The new ones corrected that. 

Working on the gas valve, blower or even changing the igniter meant that you were flat on your stomach with your arms reaching inside with your tools. It was even tough when I was a young man and never looked forward to it. 

But they performed and lasted. 

HomerJSmith

Alan, it was a liability issue. A liability issue follows you forever or until the company goes belly-up. I would check with Polaris.

gjh42

The manufacturer couldn't even find records of my serial number, said it was invalid. They finally figured it out, and said they couldn't help me, period. All they could do was give accurate part numbers (old # 6907310, newer # 100093698) to search for online. Of course nobody has one. I called Mack Stove and he said he would look into it and call back... no word yet.

gjh42

The lowest priced new Polaris is over $4000. I seem to recall I paid around $1800 for a similar (34 gallon) one in 1997. I was never able to run it out of hot water even in winter.

GGross

Have you tried entering the serial number into the parts list portal?
https://eportal.hotwater.com/Commerce/PartsList#web-app

AO Smith/American are the same, I do believe that polaris was a model by American Water Heater. Neither part number you listed comes up as something I have ever stocked before, I don't think we ever sold any Polaris models though

ratio

Negative pressure gas regulators aren't that uncommon, Trane for instance uses them. I can't imagine that it's discontinued, but maybe they don't OEM them anymore. Have your tried the manufacturer of the valve itself? I'm sure they'll tell you they don't have that particular one, but they have have one that will cross over.

Larry Weingarten

Hi, I did some snooping around and came up with these places to check out. http://bostonheatingsupply.com/polaris6903775.aspx

https://www.zoro.com/polaris-water-heater-gas-valve-for-polaris-water-he-100093638/i/G100641452/?gclid=a6ed2da9f3a1165429654f7735af40bc&gclsrc=3p.ds&msclkid=a6ed2da9f3a1165429654f7735af40bc&utm_source=bing&utm_medium=cpc&utm_campaign=ml_all_na_na_ssc_Bing Zombie Third Party SKUs Smart Shopping&utm_term=4585994283500648&utm_content=Zombie SKUs TP

https://www.ebay.com/itm/115279434817?chn=ps&_trkparms=ispr=1&amdata=enc:1g79hoshpRBGr3_OQ-TtOcw39&norover=1&mkevt=1&mkrid=711-213727-13078-0&mkcid=2&itemid=115279434817&targetid=4581046489808870&device=c&mktype=&googleloc=&poi=&campaignid=418640322&mkgroupid=1239149842233245&rlsatarget=pla-4581046489808870&abcId=9300602&merchantid=51291&msclkid=9a3e8d68b94c194a360befb67f42a6a3

and FYI http://bostonheatingsupply.com/polaris6907310.aspx

Yours, Larry
ps, Your old valve is a Robertshaw 7200DERN . Maybe they can help you with a replacement.

HomerJSmith

I have a brand new Robertshaw 7200DERN gas valve for Polaris on the shelf, imagine that. I don't know what the current value is. Send me a e-mail and we will negotiate.

gjh42

Boston Heating Supply, Zoro, and every other supply house I could find all say the Polaris gas valve for my heater is discontinued and they don't have one. Nobody on eBay says they have one either. I couldn't find information on the actual valve manufacturer, so if it is a Robertshaw unit, that is good news.

HomerJSmith

It is! It is as I described.

Larry Weingarten

Hi @gjh42 , Have a look at this link: http://bostonheatingsupply.com/polaris6907310.aspx Look to the third picture and when you scroll over it, you'll see the brand and model number. Is this valve that you currently have? If so, PM Homer J Smith and get that one he has!

Yours, Larry

HomerJSmith

The threaded two ports on my valve is the same as pictures 3&4 in Larry's post to Boston Heating. The others are blocked. Mine is a Polaris supplied valve so, gjh42, it must be the same as yours.

gjh42

I was able to get a mirror behind the gas valve and confirm that the label on the back says 7200DERN. Robertshaw says that valve is discontinued, but somebody on eBay has a new one for $95 plus shipping (they obviously don't know that is a replacement for a Polaris unit).

HomerJSmith

BUY IT!

gjh42

I found a website (surpluscityliquidators.com) that has 40+ of this valve for $76 each ($91 total with shipping)... turns out it is the seller of the one on eBay
It's on its way.

gjh42

Much struggle and searching later... I received the gas valve... it is a match for my old one except that it has only a straight-through outlet, not the back outlet option that my old one uses. This would require running the gas supply in the access opening rather than through the sidewall of the pedestal enclosure. I have talked to numerous local plumbers, the individuals were either scared to work on it or never returned numerous calls, and the companies refused to work with my customer-supplied equipment even though they couldn't have gotten one from the manufacturer either.

I checked the rest of the wiring and connections and found the white wire from the main feed had a bad spade connector which I replaced, and now I get 26 volts at the gas valve instead of 15 volts. Still doesn't work.

I am about ready to replace the valve myself, but need to know if the factory replacement would be set for natural gas or propane, or is agnostic. Nobody including tech services at Robertshaw can give me any information whatsoever, nor is there any indication of gas type on the valve body. The valve is assembled with tamperproof screws, so if there is a conversion to be made it must be associated with one of the threaded inserts on the top or ends of the valve. Does anybody know whether this valve needs to be converted, and if so how it would be done? I have converted burners to propane before so am not worried about that process if I have to do it.

The original has a 1/8" aluminum tube running from the 1/8" NPT connection labeled "vent" to the burner, while the new one has a sheetmetal cap inserted in that location (a shipping cover that pries out with thumbnail pressure). Next to that is a 1/8" NPT plugged connection labeled "out press" (perhaps for testing, or for adjustment?). These are above the 3/4" NPT gas outlet.
There are labels cast into the body for "pilot" and "pilot adj" but I think these are irrelevant to me.

gjh42

Can anyone tell me if the Robertshaw 7200DERN gas valve I have needs to be converted to propane for my Polaris water heater or is good as is, or what needs to be done at installation aside from connecting it?

Alan (California Radiant) Forbes

Not sure, but tech. support will know. (800)456-9805

They will ask for the model and serial number.

gjh42

Robertshaw tech support could give me no information whatsoever about this discontinued gas valve. It was erased from their database.

American Water Heater (Polaris) could not even tell me who had manufactured the valve let alone how to handle it.

Larry Weingarten

Hi, A thought. If there are no specs that came with the valve that could help determine what type of gas it's set for, how about hooking it up with burner to propane, outside of the heater (and outside of the house) and see what flame you get. If it's a normal flame, you're good to go. If it's too big, the valve is set for natural gas.
Probably a saner approach is to find and call a local independent parts distributor and see if they can help. Have a look here: https://www.apda.com/

Yours, Larry

hot_rod

I guess there is no sticker on it or the box indicating if it is NG or LP. Usually they are labeled somewhere.
If an LP kit was used, there would be a yellow sticker included to relabel the valve

gjh42

After a couple more failed visits from professional companies, and repairing a few bad spade connections and replacing a couple of electronic boards, I finally bit the bullet and did the gas valve replacement myself. I had to use a weird gas piping routing, but it works normally and seems to be set correctly. I think it may be built so that the negative pressure from the blower intake regulates the valve outlet volume/pressure, making it agnostic as to propane or natural gas.

Thanks for the advice from various people here, you were more helpful than most of the pros who actually looked at the heater.

gjh42

A note that may be helpful to somebody else: The exhaust is so low in temperature that vapor condenses in the plastic pipe, and they provide a trap with outlet to drain condensate from the exhaust. I ran a 3/8" poly tube snaked around the back to a drain, and this connection (in a nearly inaccessible location) had been leaking for decades, keeping the base of the heater damp and causing some of the corroded spade connectors and probably other damage. Before starting the heater for the first time in a couple of years, I cleaned out the access route and got the old connection off… the brass compression fitting was completely eaten away by the condensate. I replaced it with a PVC plug with a friction-fit hole drilled in it and sealed with E-6000 glue, which hopefully is acid-resistant for the long term. It has not leaked yet…

Use only plastic drain materials for the exhaust drain on a condensing high-efficiency gas water heater!