Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.
If our community has helped you, please consider making a contribution to support this website. Thanks!

How to delete boiler coil and replace it with a HPWH

Options
2»

Comments

  • nelaco
    nelaco Member Posts: 21

    Well, the coil is leaking inside the boiler so it is history. When I flushed it, the bucket kept rising in water level. Lowe's postponed the delivery of the HPWT from last Friday to tomorrow…fun times.

    @EdTheHeaterMan , I just tried this but the wires won't come off. Do I need to take the white box appart and undo them from the inside or just pull them very hard? I am planning to replace the coil since I already have a new one that I bought months ago that I can't return. It would be nice to have it as a backup and would also solve a small leak by the coil cover.


    "L8184A,C,G or L is easy to do by removing the Rand W wires from the LO limit side of the control and connecting them together. That changes the control from a maintaining minimum temperature for DHW to a cold start boiler."

    Thank you!

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 11,588
    edited December 9

    @EdTheHeaterMan , I just tried this but the wires won't come off. Do I need to take the white box appart and undo them from the inside or just pull them very hard? I am planning to replace the coil since I already have a new one that I bought months ago that I can't return. It would be nice to have it as a backup and would also solve a small leak by the coil cover.

    Screenshot 2025-12-08 at 8.47.53 PM.png

    To remove the wire from the white aquastat: use a pocket screwdriver to depress the release and the wire will pull right out.  the small rectangle next to the wire opening is the release.  

    Don't take the white box apart

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • nelaco
    nelaco Member Posts: 21

    Yep, now that you pointed it out I see it. Thank you @EdTheHeaterMan !

  • nelaco
    nelaco Member Posts: 21

    I finally got the HPWT yesterday and installed it. I am so impressed! What a difference. Not only we are getting plenty of hot water, but also a lot more pressure than before. Very happy with the purchase. It is a Rinnai REHP80.

    Of course now my boiler is getting too much pressure. I already called the service to come take a look. I get about 32 PSI. The coil is 100% isolated so I am not sure where the extra pressure is coming from. There is not city water going into the coil. The expansion tank is about 3 years old. We'll see what they say.

    Thank you everyone! Appreciate all the help!

Categories