Harman p68 UPS installation for power outage question

[Curtissk]

Thinking about installing an uninterruptible power supply to my 2006 P68 Harman stove. I'm considering only going through the exterior wall about 2' with the vent, and I'm concerned about smoke escaping into the house in the event of a power outage.
I'm not interested in having the stove operating during the outage. I just want the exhaust fan to function for a safe shutdown.
Harman recommends a Tripp Lite Internet 750U. Can anyone tell me if this device would power my stove into a safe shutdown?

 

[bogieb]

I use APC BE850G2 (850 VA 450w) UPS for both my Harman's (here is a link to Amazon). The stoves do shut down gracefully, pulsing the fans to keep the smoke evacuated when power is lost. I actually had that happen the other day as I had a brown out (probably a phase shift or whatever) for a few minutes.

I think these do go on sale on a regular basis (at least the 750's did before they were obsoleted). So you may want to wait and see if there are any Black Friday deals that pop up.

I think the main thing to make sure of when using a UPS for the Harman pellet stoves in this manner is to NOT get pure sine wave - otherwise the stoves won't sense the difference.

 

[bogieb]

BTW, the UPS should work with your older stove without changing any settings unless you have changed the control panel out. Newer stoves (I'm not sure when it started, but after 2014 for sure), may need a change in the dip switches to get the graceful shutdown functionality.

 

[Whitenuckler]

BTW, the UPS should work with your older stove without changing any settings unless you have changed the control panel out. Newer stoves (I'm not sure when it started, but after 2014 for sure), may need a change in the dip switches to get the graceful shutdown functionality.

Do you have any links or other information that I could look at that to read more about this special PWM sine wave mode Harman's use to pulse the fan? I have heard of a stove design (I think, not sure where) that took a special output from a UPS to tell it to it to shut down, but I have never heard of the mode you are describing.

 

[Whitenuckler]

Do you have any links or other information that I could look at that to read more about this special PWM sine wave mode Harman's use to pulse the fan? I have heard of a stove design (I think, not sure where) that took a special output from a UPS to tell it to it to shut down, but I have never heard of the mode you are describing.

Did some digging.

https://downloads.hearthnhome.com/brochures/HAR-0040U-0718_BatteryBack-upOptions.pdf

I looked up some of those Tripp Lites they say are for continuous operation and some are modified sine wave.
You are right some models with a screen have some sort of setting.

They say even a knob stove has a setting on the switches:

https://d3munzpmppxgon.cloudfront.net/1003/resources/1197600.pdf

Not quite sure how this all works but you are 100% correct. I have pure sine wave and a big battery so I have never did any testing. I run on the inverter all the time so when it kicks off I would dead. I am in the basement with OAK so probably would not get any smoke anyway.

 

[Curtissk]

BTW, the UPS should work with your older stove without changing any settings unless you have changed the control panel out. Newer stoves (I'm not sure when it started, but after 2014 for sure), may need a change in the dip switches to get the graceful shutdown functionality.

Bogieb, thank you so very much for your input!! A big concern of mine was if something would need reprogrammed on my stove? I will look into purchasing one of these UPS's. I bought the stove used in 2019, so I'm hoping the previous owner didn't change out the control panel.
This electrical stuff is so above what my brain understands!

 

[bogieb]

Do you have any links or other information that I could look at that to read more about this special PWM sine wave mode Harman's use to pulse the fan? I have heard of a stove design (I think, not sure where) that took a special output from a UPS to tell it to it to shut down, but I have never heard of the mode you are describing.

I do not have info. But, when it came time to replace my UPS, I took special note of the specs on the originally approved UPS units and the differences between the BE750G versus other 750 models by the same manufacturer. That is how I arrived at the BE850G2 as a replacement model (or the RBC17 as a replacement battery)

Versus the battery:

I also may have read it in a post somewhere here - that was way long ago.

 

[Whitenuckler]

I do not have info. But, when it came time to replace my UPS, I took special note of the specs on the originally approved UPS units and the differences between the BE750G versus other 750 models by the same manufacturer. That is how I arrived at the BE850G2 as a replacement model (or the RBC17 as a replacement battery)

View attachment 342608

Versus the battery:
View attachment 342609

I also may have read it in a post somewhere here - that was way long ago.

I did some digging and posted yesterday - I actually had the documents and posted some links at 10:54. I guess what ever I read I had forgotten. Thanks for helping. I'm still not sure how they make it work, the UPS that is not sine wave ect, and do the pulsing of the combustion blower. Somehow the board can detect the temporary UPS power.

 

[mtnbiker727]

BTW, the UPS should work with your older stove without changing any settings unless you have changed the control panel out. Newer stoves (I'm not sure when it started, but after 2014 for sure), may need a change in the dip switches to get the graceful shutdown functionality.

How would I go about changing the "dip switches" on my 2018 P68?

 

[Whitenuckler]

How would I go about changing the "dip switches" on my 2018 P68?

https://d3munzpmppxgon.cloudfront.net/1003/resources/1197600.pdf

You will need to take your card out and verify to this chart. As for making the change, what you will see is a multiswitch
"block" on the card. You then just need to use a thin flat screwdriver to "rock" the switch to another position. According to
the document it is only one switch of the many on the "block"you need to possibly switch.