Harmon Accentra Low Draft Setting

[investor7952]

I have read a little about this in my book but have no idea if the dealer did do this.Is this something I can do .First what the heck does it do?

 

[Lousyweather]

I have read a little about this in my book but have no idea if the dealer did do this.Is this something I can do .First what the heck does it do?

Possible, if the dealer did a draft test on install. Dont mess with it unless you have a magnehelic to set it correctly. It varies the voltage slightly to the comustion fan.

 

[TomPajak]

How do you tell if its out of adjustment..turned mine up and down from the original spot and CAN hear a slight difference in speed but it seems to do a fine job job on the lowest setting sitting at idle..so why change it?
its back to the original spot but was just curious

 

[Lousyweather]

Yea, HP68, they are set at the factory, usually maxxed out. Theres no way of setting it correctly without checking draft. Yeas, its likely you might hear a difference, but its only slight, as the pot only changes the voltage by several volts......not 10's ov volts, etc.

 

[TomPajak]

Yea, HP68, they are set at the factory, usually maxxed out. Theres no way of setting it correctly without checking draft. Yeas, its likely you might hear a difference, but its only slight, as the pot only changes the voltage by several volts......not 10's ov volts, etc.

mine wasn't maxxed..matter of fact it basically is in the middle...can't see what the big deal about it is..if it doesn't help or hurt ,why have it..does any other stove maker have 1??anyone out there have 1 of these besides Harman?

 

[Lousyweather]

Im lead to bedlieve its there to lessen the draft in certain high-draft situation....a mean to slow down the combustion fan.....might be wrong tho.....if its set "in the middle" then it would also seem to be a means to increase draft if it were needed. Thing is, when we do an install, we test the draft, and note the reading. When we have to go our for a "stove issue", one of the first things we do is again, test the draft. If it differes significantly, its usually a cleaning issue....plugged exchanger, plugged pipe.....so, if someone messes with the potentiometer, say, lowers it, then it messes us all up!

 

[crausch]

The "low Draft" should have been set during installation but usually the factory setting is ok. To correctly set it you would need draft meter or a magnehelic guage as "lousyweather" mentioned. If you lost your original setting, I have heard another knowledgible member say that you can turn it fully clockwise then back it off a 1/4 turn. Usually is sufficient for most stove setups.

Low draft is used when the stove is running on a low output (less air because you have less fuel) in this instance it is for efficiency (less air, less heat loss out the exhaust).

Low draft is also used during start up so that the air can pick up more heat as it goes through the ignitor’s heat transfer fins. If low draft is set too high, you can have sluggish ignition.

High draft is not adjustable, it is determined by your set up and the actual voltage available to the stove. The control board just sends full line voltage to the exhaust blower. On low draft the control board sends about 7/8 of line voltage to the exhaust blower

 

[pkitfox]

I bought a magnehelic meter off of ebay. It cost $26.90 including shipping. I measured high and low draft according to the owners manual. High draft measured .57, and low was .52. Our stove is burning perfectly, as far as I am concerned, so I left the adjustment alone. The low draft is quite high according to the manual, but we are getting reliable ignition, and reliable burn on the lowest stove temperature setting.

 

[timjk69]

I tested the draft on my Harman and found it to be excellent. I ended up turning the low draft setting all the way up though to get a cleaner burn.