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Marc, Plumber
Category: Plumbing
Satisfied Customers: 1127
Experience:  Plumbing heating & home maintenance contractor
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I have a PH-5-3H tankless heater that the main burner will

Customer Question

I have a PH-5-3H tankless heater that the main burner will not fire up. It is used, but in excellent condition. It is set for propane and water pressure is around 50 PSI. Pilot light works fine.Wassup?
JA: How long has this been going on? And how severe is the problem?
Customer: This is a new installation.I am using two 40 lb tanks with an automatic switchover. The tanks are below the heater with a short pipe run.
JA: Do you plan on doing the work yourself?
Customer: Depends. I'm a retired mechanic, but at 76 may or may not want to fuss with the problem myself (short on patience-comes with old age).
JA: Anything else we should know to help you best?
Customer: The only adjustment I can see is on a squarish device on the left side with a phillips screw in it. I do not have the original paperwork and have no factory data to work with.
Submitted: 1 month ago.
Category: Plumbing
Expert:  Phil replied 1 month ago.

Hello, lets do a few tests.

First turn on 3 hot taps in the house and tell me if the water heater fires up not.

Next I need the brand name to go with that model number, I can possible find an old manual for it.



Important note about RATING my work:

I am a retired mechanical engineer and HVAC/electrical/ refrigeration and boiler contractor ... with 56 years in this business. The last 20 of those years consulting for major firms nationally..


All I ask is please respect me and my input by selecting the***RATING LINK***at the top of your page, that is the only way I am credited through the site. Rating does not affect your charges nor ability to refund if not satisfied.


If you need to be coached through a full diagnosis/repair,and wiring etc. for up to two days, and wish to be trained to use test instruments...... that goes well beyond' Just a simple Answer' of course, and goes beyond what most other experts here offer.....rate my simple answer so far positively.. and I will deliver that training and coaching to you All on the same dime so to speak.


Lacking a positive rating I can spend days helping a person at my own expense and loose my shirt, shorts and socks on the deal.


Attach a close up photo of the wiring diagram glued to the inside of the blower access door and I will mark it up with trouble shooting instructions then follow up with step by step training and coaching until you have a solution.


Photo must be exceedingly well focused. Use the 'add files' link next to your send button to get the photo to me.


Phone call offers:

If you wish to accept the companies $25 phone call offer, if indeed they send you one, this will go a *lot faster, but it IS 100% optional... or we can continue here in this dialog box at no additional charge.

Customer: replied 1 month ago.
Cancel my call for help l will take it to a place that will make it work
Expert:  Phil replied 1 month ago.

That is fine, however you need to know that where ever you take it will not generally be set up to connect it to water and gas, in order to check it out... few if any outfits will be interested in checking it at their shop for that reason.

Good luck with whatever you do.