EFM 350

markviii wrote:Yeah!!!! Hopefully all the threaded connections stay water tight and you just have to sit in the chair and watch the flames. 4 teeth / 4 air?

-Rob

If your burning Rice in it Yes 4 & 4 Is a good starting point But with Buckwheat size you need more air 6 to 6.5 feed 3 to
4 teeth . 4 in this weather

Wood'nCoal wrote:I had a leaky fitting, the first reducer I installed in the bottom of the boiler, which has been under pressure for weeks now. I have looked at it twice since firing the boiler, it seems to have stopped leaking. I'm at 3 teeth, 4 air right now, I may go up to 4 teeth. My draft is good, -.04" WC on the pipe before the baro, but it drops to -03" if I raise the air to 5. The chimney drafts very well, but the oil-fired DHW heater is still connected and the blower in the EFM sure can move a lot of air.
I have to go check it again (every 15 minutes or so!).

You going to need more air if you burning buck unless you want to sift coal out of ash tub. .03 to .05 is fine for the stack draft . Over the fire air .02 but .01 is fine as well . look at you inside stack temp watch that go up to as you increase the air adjustment . Mine is 325f at 6.5 air at 4 air you will be at 275 to 285F.
Well if you had a fan on your mouth spinning at 1725 RPM's you would move a lot of air to

I was on a warranty call recently where I found that the factory installed front-bottom plug was weeping. Cool as ice, one of the dealer's men backed out the plug until a streak of water was shooting out across the room, coated the plug with a special sealant and turned it back in. It had to be on its last thread. Problem solved.

He never isolated the boiler, or even reduced the pressure.

Wood'nCoal wrote: My draft is good, -.04" WC on the pipe before the baro, but it drops to -03" if I raise the air to 5.

Did you take that draft reading with the boiler up to temperature? As long as you have negative pressure at the firedoor all should be well.

-Rob

The boiler is running well, I was surprised how little ash there is so far. It is truly "automatic". The heat exchanger is working well. This was a hell of a lot of work and $$ but I'm happy I did it. The heat exchanger did reduce the air flow in the ducts a noticeable amount, but it seems to be working. I'm still burning the Harman for a radiant heat source and for heat in the kitchen. I'm planning on keeping it for the colder weather, even though the EFM can handle the heating.
The only problem right now is if I raise the air above 5 it pressurizes the firebox, I tried it at 6, no good. The oil-fired DHW heater is still connected to the chimney as well. I had no problem leaving it connected with the Akaska, but it had a much smaller combustion fan, so the air is at 5. I peeked in at the ash ring and yes, there is some unburnt coal, but not much. I have the feed at 4 teeth now and the aquastat differential at 10°. I'll get a 6" cap for the pipe to the DHW heater and cap it off and see what happens. My chimney drafts very well, but there's a limit to everything. The baro is not opening at all. I haven't taken an overfire draft reading yet, the pipe draft stays between -.03" and -.04" WC.

Did you take that draft reading with the boiler up to temperature?

Yes I did. The Man-O-Meter is still connected.

So far so good.

The DHW is good, I think I have the tempering valve set right. The DHW oil burner is OFF. I still keep checking the boiler often. The leak seems to have stopped.

What size is the flu pipe? How many elbows and Tees?

8" pipe, 2 elbows, 1 tee for the baro and one tee at the chimney connection. The chimney is about 2 1/2 stories tall, fieldstone, 6 X 6 liner, but the flue is not straight.

Everything but the liner size sounds good. 6x6" is tight for that volume of air.

4/4 with rice didn't give you an acceptable burn?

-Rob

Wood'nCoal wrote:The heat exchanger did reduce the air flow in the ducts a noticeable amount, but it seems to be working.

John, you may want to go up one size on your blower motor. If you have a 1/4 HP motor, go up to 1/2HP to overcome the induced blockage/back pressure caused by the Heat exchanger.
You'll find out how much extra strain is bing put on that motor by how long it takes to burn out.

markviii wrote:Everything but the liner size sounds good. 6x6" is tight for that volume of air.

4/4 with rice didn't give you an acceptable burn?

-Rob

Agreed, but changing the chimney size is not an option!
Didn't run rice, went with buck. Changing that is an option.

Well, Chris, we shall see. I don't know what HP the blower motor is. I do know that the furnace was starved for return air, there are only 2 ducts, both on the living room floor. That in itself was a strain on the motor, it may be working less now with the heat exchanger in place.

Did you change filters, the better filters are more restrictive, I noticed a big difference, so I keep using the cheap ones. There is always dust for the wifey to chase.

There's a mesh permanent filter in the furnace. It probably needs a cleaning. Last time I cleaned it I noticed writing on it recommending a spray that is supposed to be applied before the filter is reinstalled. I guess I should check the filter.

Congrats on your install John!

Thank you.

Wood'nCoal wrote:There's a mesh permanent filter in the furnace. It probably needs a cleaning. Last time I cleaned it I noticed writing on it recommending a spray that is supposed to be applied before the filter is reinstalled. I guess I should check the filter.

I think I have a spray can of K&N oil, you can have, but I bet that wouldn't be too nice to be smelling inside the house