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Boiler power...

SkylineSkyline Member Posts: 42
As someone, whose boiler literally got burned by power surges, I made some changes to the old boiler's power:

This solution has been working just fine, also added one for my daughter's Navien Boiler.

For my wall mounted boiler, I am considering adding a UPS that has built-in surge protector, effectively removing the Isobar surge protector. My house does have a standby generator backup, but still would want to add a UPS.

I don't see any reason why this would be against building codes and/or manufacturers warranty. Does anyone can confirm and/or contradict this statement?

There are number images posted on this site for completed boiler project, but yet to see one that have have surge protector. Not seeing it does not meant that there's none, people could have the surge protector in the breaker panel, somewhere along the line, whole house protection, etc.

Boiler controls are computerized and they are just as sensitive to fluctuating power and/or surges, than any other computers. The last time my house had the surge, it costed me six to seven hundred bucks; including all the surge protector strips that burned up, but protected the computers and the TV.

Two hundred bucks of surge protector seem like a bargain for the boiler...


  • kcoppkcopp Member Posts: 3,523
    I have been doing it that way for several years. I use the $15 dollar 1000 joule suppressor from a big box store.
  • WellnessWellness Member Posts: 105
    edited September 5
    While I see no harm in surge protecting boiler controls, the Taco control is no more "computerized" than a refrigerator or most other household appliances. For me, surge protection is most critical on electric components with volitile memory or those that requires power to retain stored data, such as computers, some HVAC thermostats that lack battery backup and similar devices.
  • psb75psb75 Member Posts: 231
    I have replaced motherboards in heat pump water heaters and pellet boilers probably due to power surges from unsteady power in rural electric grids and lightning strikes.
  • Jamie HallJamie Hall Member Posts: 13,209
    An interesting situation. Hopefully it won't be too long before newer equipment with sensitive electronics -- which is becoming more and more common -- will start to have power conditioning built into it. In the meantime, power conditioning -- beyond simple surge suppressors -- is not a bad idea at all, since with the increasing amount of distributed power (solar cell arrays, wind turbines, what have you) coming on line power is getting "dirtier" and dirtier (in the electrical sense of dirty -- lots of higher frequency harmonics creeping in, odd spikes and dropouts, etc.) and that is only going to get worse.
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • jumperjumper Member Posts: 1,502
    Ubiquitous electronics has created a new industry. Power conditioning. A whole house conditioner does not protect one electronic gizmo from mischief another makes. I remember auto-transformers and that was before electronic motor control.
  • JUGHNEJUGHNE Member Posts: 7,115
    What I have done for people who have non auto whole house generators is to put a good power cord on the furnace or boiler.
    Change the disconnect switch to a high quality single outlet.
    (Yes, should be a GFCI outlet, but the furnace would always be using that single outlet until power failure)
    Just plug in for normal operation.

    Then with no power to the house they can run their small generator, stretch a # 12 extension cord thru the basement window to the furnace/boiler.
    The cord on the unit is probably not correct to code, but my inspector understands the reasoning and has said nothing.

    The power vent WH next to the furnace is factory cord connected anyway. The HO then has to ration power out to heat, WH, freezer and fridge as needed.

    Another advantage to the cord connected boiler is that a high quality UPS with high end surge protection could then be cleaning up the power for the boiler.
    Certainly could run a steam boiler for quite a while on battery.
    And maybe HW boiler for a bit depending upon how much pump power was needed and the size of the UPS.

    I have fair sized UPS's for our computers.
    They feed the phone chargers, Ipad chargers, modem and small desk lamp.
    But not the printers.
  • SkylineSkyline Member Posts: 42
    Power surges are non-dicriminatory, when it comes, it'll burn everything in sight.

    In my case, other than the boiler and surge protectors getting smoked, the gas stove's circuit board burned up as well. Repair by the service guy would had been close to 500 bucks for the stove. Ordered one online for less than 200 bucks and replaced it myself.

    Since then, other than lights, everything has a surge protector in my house. Yes, including the stove, fridge, washer, dryer, etc. 30-40 bucks per surge protector is cheap insurance. The CyberPower CP1500 is even better insurance for the boiler for around 200 bucks.

  • mattmia2mattmia2 Member Posts: 1,741
    JUGHNE said:

    What I have done for people who have non auto whole house generators is to put a good power cord on the furnace or boiler.
    Change the disconnect switch to a high quality single outlet.
    (Yes, should be a GFCI outlet, but the furnace would always be using that single outlet until power failure)
    Just plug in for normal operation.

    I would use a twist lock and leave a twist lock cord to plug it in to an extension cord for the generator. Still required to be gfci protected now in most jurisdictions, but makes it a lot harder to plug something else in to the circuit for the furnace. I think technically the issue is that the furnace is listed for hardwire only.
  • SkylineSkyline Member Posts: 42
    I finally got around to insert a UPS, Cyberpower CP1500PFCLCD 1,000 W, in to the power feed for the boiler. It's been a bit more complex, than it should had been due to the former boiler's wiring, but it's done.

    My first test was succesful. Shutoff the braker for the UPS utility power and turned on the boiler. It started up without an issue, the boiler went through its start up procedure and stayed running for couple of minutes because of the DHW. The UPS showed under the current load 55 minutes remaining on the backup battery. While this is nice to have, I am more satisfied with the voltage regulation, surge protection, etc., features. Couple of C notes and a little elbow grease well worth for all of these features.

    My generator has manual transfer switch, by choice. The close to an hour time on battery backup gives me plenty of time fire up the generator.

  • Jean-David BeyerJean-David Beyer Member Posts: 2,665
    edited September 26
    My house has a 12 KW natural gas fueled backup generator that automatically comes up and runs the house within 10 seconds of a power company failure (or severe voltage drop). My main power distribution panel has a whole-house surge protector in it. My computer has an APC SmartUPS UPS running it and contains a serious surge protector in it.

    My Taco hot water circulation system has a controller that learns my usage over a week and projects when to run the next week. As far as I can tell, it cannot stand power interruptions. So I stuck a small UPS to run the controller and the circulator. But I do not think this is quite enough as it enters the learning phase rather often. I get lots of power flicks around here, typically less than a second or two. The UPS usually switches on in one cycle time.
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