Harman Pb105 Not HEating with Low Temps

[Chris04626]

My boiler has been running fine, since we have been down to 15 degrees and lower we are down to 63 in here. Whats going on? I have MAx set to 185 and low set to 160 and feed 5

cleaned ashpan, and fines areas?

Also my feeder has devolved a squeal when it turns

 

[harttj]

What has the consumption been? More pellets equal more btus. With 105k btus at the disposal should have no problem.

 

[Chris04626]

2 to 2.5 bags a day

 

[harttj]

2 to 2.5 bags a day

Assuming 80% efficiency this equals just over 21,000 btu per hour. Don't know your heat load but it could easily be more than that.

 

[Chris04626]

i have a 1800 square foot house, 1978 2 story home. No heat upstairs. All new windows

 

[Chris04626]

should i put up the feed rate?

 

[harttj]

I'm not real familiar with your appliance. Either turn the feed rate up if your not holding water at the setpoint or your limed in how much heat you can pull out( plugged heat exchanger?)

 

[ScotL]

Mine is burning almost 4 bags per day right now. I can thank my wife's sunroom for all that heat loss.
Is your boiler getting up to temperature at all or is it unable to keep the water hot enough? If it's not heating the water to the full 180 or so you have it set on, then it's not burning enough fuel. If the water temperature is nice and hot, then the problem would be the transfer of that heat throughout your house.

 

[Chris04626]

YEs the boiler is getting itself up to temp and turning off. thermostat is set at 67 and its only getting 63 in here once in awhile 64. Its about 9 degrees downeast here. Its been working fine keeping it at 70 we had it set on easily until temps really fell. What settings do you have yours on now?

 

[ScotL]

My settings are about the same as yours. 155 to 185 with a feed rate of 4 to 4.5. But if your boiler is getting up to temperature then all that heat isn't being delivered to your registers like it should be. If the oil boiler used to be able to keep the house warm, then the size of your registers isn't a problem. That leaves the flow of hot water from your pellet boiler to your oil boiler. Is the water temperature on the outside of the oil boiler showing the same as the water temperature on the pellet boiler?

With your pellet boiler getting up to temperature, it sounds like a circulation problem to me.

 

[Chris04626]

temp on the oil boiler reads is 180 and the pellet boiler just shut down because it reached its temp that shows like 220 but i think its off

 

[ScotL]

So your pellet boiler is working like it's supposed to. It's providing the heat then shutting itself off. The rest of your system isn't taking that heat and delivering it to your baseboard registers, or the registers are undersized - which is doubtful if you never had that problem with the oil boiler. But maybe the oil boiler did the same thing? If your hot water baseboard system was providing enough of a heat sink, the pellet boiler wouldn't be shutting off until the house was warm and the circulators shut off.

 

[iceguy4]

cleaned ashpan, and fines areas?

have you cleaned the fan, fan housing, area behind the lower access panel, esp,chimney?

 

[SmokeEater]

if you have enough baseboard to handle the output of the pellet boiler then the boiler should bring you home up to thermostat settings. Again, if it is not the answer could be as simple as an air lock. All all of your heat units hot when there is a call for heat by the thermostat? Check the inlet plumbing to see if is carrying the heat or if the water is blocked by air. Are the zone valves opening? Circulators running? Good luck.

 

[Chris04626]

So your pellet boiler is working like it's supposed to. It's providing the heat then shutting itself off. The rest of your system isn't taking that heat and delivering it to your baseboard registers, or the registers are undersized - which is doubtful if you never had that problem with the oil boiler. But maybe the oil boiler did the same thing? If your hot water baseboard system was providing enough of a heat sink, the pellet boiler wouldn't be shutting off until the house was warm and the circulators shut off.

No oil boiler did not heat the house well when the temps cost real cold. But whats funny with this though we had temps 15-20 and the pelelt boiler was heating to 70 easily, but now its gotten down below 10 and sometimes 15 it will not get over 64

 

[Chris04626]

have you cleaned the fan, fan housing, area behind the lower access panel, esp,chimney?

Yes fan and esp was a little black vacummed and wiped clean

 

[Chris04626]

if you have enough baseboard to handle the output of the pellet boiler then the boiler should bring you home up to thermostat settings. Again, if it is not the answer could be as simple as an air lock. All all of your heat units hot when there is a call for heat by the thermostat? Check the inlet plumbing to see if is carrying the heat or if the water is blocked by air. Are the zone valves opening? Circulators running? Good luck.

I have felt on piping coming too and from oil boiler as well as pellet boiler and they are all hot to touch.

 

[iceguy4]

temp on the oil boiler reads is 180 and the pellet boiler just shut down because it reached its temp that shows like 220 but i think its off

If this is the case you cant ask more of your boiler. Based on this info your problem is in your delivery system.. Either you don't have enough "radiators" (be it fin tube, cast iron...) or Circulator...'s are not up to par, Or you have air in the system. EVERY zone should have a boiler drain on the opposite side from pump (if your circ is in the return , boiler drain in supply) This will enable you to run the circ and flush air out at the same time.
Also I cant recommend enough...Air ejectors. NOT those valves on elbows at the end of fin tube runs we so often see! I'm talking about an air scoop with expansion tank on bottom. I have 3 on my system. one installed with my oil burner install with a spiral air ejector. when I installed pellet boiler I added another less the spiral ejector (I chose the cheaper brass one . when I hooked an additional building I added a third. so I have 3 expansion tanks, 3 cast iron air scoops and 3 air ejectors.
The reason I'm going into such detail is I'm betting air IS the problem. You understand the larger the pipe, the harder it is to get trapped air out. Look this link over...(broken link removed to http://www.taco-hvac.com/uploads/FileLibrary/AirElimination.pdf)
I just had to bleed air out of my 2nt house circuit (aprox 150' of 1 1/4 iron pipe) I had a LOT of problems and even thought my circ was bad...it wasen't....it was air

 

[hossthehermit]

Set your thermostat higher and see what happens........

 

[moey]

You mentioned not heating the upstairs if its open that could be a big problem. The baseboards would not be able to handle doing the load upstairs as well. You are only going to put out so many btus per ft regardless of the size of the boiler. You either need more baseboard or higher temps in the baseboard. Or maybe air somewhere. Just ideas.

 

[chken]

If the room is not getting up to the thermostat setting, is the hot water constantly circulating thru your baseboards? If it's not, then maybe the circulator valves are not functioning, though it seems unlikely if you are getting to 64 degrees. More likely, your baseboards are undersized. Measure the linear footage of baseboards in the room that is cold and then take the area of the room and exterior wall length and plug it into a baseboard calculator. I know there's one at Pexsupply.com

Your pellet furnace could go thru 7 bags a day, I believe, so it's not that. Sounds just like you're not getting enough hot water thru the baseboards, because the baseboards are too short.

 

[Chris04626]

The guy that installed it came, he turned up the speed of the circulator and turned down the aquastat a little bit(not sure what this does) but you could feel the baseboards are actually hotter and the temp raised some. HE recommended adding a few more sections of baseboard to the downstairs. Which he said would cost 1000-1500. Said it would cost ALOT to get heat ran to the upstairs.

The upstairs is not open space stairs goes to a hallway which has 4 bedrooms.

 

[chken]

The guy that installed it came, he turned up the speed of the circulator and turned down the aquastat a little bit(not sure what this does) but you could feel the baseboards are actually hotter and the temp raised some. HE recommended adding a few more sections of baseboard to the downstairs. Which he said would cost 1000-1500. Said it would cost ALOT to get heat ran to the upstairs.

The upstairs is not open space stairs goes to a hallway which has 4 bedrooms.

Didn't know circulator pumps could be adjusted! The baseboards, in theory, should be as hot as the water coming out of the furnace, so if the first baseboard in the loop didn't seem as hot as the water coming out, 180 degrees, then it's cooling too fast. Insulating the pipe would help, and I guess in this case, the water was moving too slowly and cooling down.

I'm guessing the water in the pipes shouldn't cool off below 140 degrees before returning to the furnace. That's because the fan units I have in my kitchen require 140 degrees for them to turn on.

As for the cost, you need to go to pexsupply.com and use their calculator to determine the amount of baseboard you need. Using PEX and shark bite fittings is a pretty easy job for a DIYer and not that expensive, if you are just adding a piece, or replacing a piece, in each room you are heating. Running a loop upstairs is not that hard, as long as you have a way to thread the PEX up there.

 

[Chris04626]

what exactly does the aquastat do on a pellet boiler?

 

[SmokeEater]

The control panel on the Harman boiler has a max water temp adjustable set point and a min adjustable set point. You, as the operator, can set those temps withing the limits the panel will allow. Then sensor for these set points is the aquastat that indirectly controls the feed rate and the combustion fan draft. Control panel receives input from the aquastat and through a timer (I assume) can shut the boiler down if there is no call for heat over a time period. The aquastat is a major role player in the boiler's operation.