longwood series v11, no heat from the registers upstairs.

jonesg

trying to help out a retired neighbor who isn't used to the cold weather, from columbia.

We live in northern Maine, it gets nasty cold here, she used elec heaters throughout the house and it was a stiff elec bill every month.

She had a heating company come out and they wanted $25K, obviously to install a new system but she don't have that sort of cash.

i looked at the furnace, the oil burner functions, as does the big squirrel fan and the heat reclaimer but we aren't getting hardly any heat at all from the vents upstairs. the circulation fan cycles on and off, maybe one minute on 4 minutes off.

theres 2 thermostats on the wall upstairs, i don't know which one is which.

Should I start removing panels to explore the heat exchanger?

ducting all looks good.

Or is there something preventing the air from circulating around the firebox.

i took a short video ,

https://youtu.be/AYIzdMBnD08?si=zLvQaQEv4YMALZJf

Jamie Hall

Let me ask a slightly different question: are you getting very little or no heat from the vents upstairs, but a nice breeze, or is it that you are getting very little air flow?

And what about the vents downstairs? Are you getting air flow but no heat, or are you getting very little air flow?

In any case, it wouldn't hurt to have someone come and clean and adjust the furnace. They do need maintenance! But if your air flow is down — which it sounds like it may be — find out what is obstructing it. Filters? Dampers closed anywhere? Where does the furnace get return air?

jonesg

thanks for replying,

it has airflow, i would say slightly down but we can definately feel it, there is slight warmth in the flow, just not what it should be.

i'm going over there soon with an idea what to look for, i'll post results.

leonz

As Brother Jamie said she needs to have the furnace cleaned and tuned up.

Forced air/scorched air systems rely on ONLY ONE thermostat as this controls the temperature and activates the burner and blower.

She may very well have a clogged air filter that is impeding the air flow to the registers.

This drives the squirrels crazy as they are working harder than they are supposed to.

The air filters are located in the steel box attached to the furnaces plenum.

The squirrel cage blower rests on the bottom of the box and blows air through the twin filters

The first thing you should do is open the access door for the filters to see how clogged they are and if she has new ones replace the old ones.

Then you determine which thermostat is actually controlling the furnace blower and burner by tracing the wires if possible or simply pushing the adjustment lever down all the way on both of them and then raising the first one until you hear the furnace start. If the second one is still in the off position I would just not use it as it is doing nothing.

jonesg

I pulled the panel off the front of the exchanger, everything is clean inside, I was expecting tons of rust and rot but it looks ok to my eye.

The only damper is a small 5 inch dia flapper at the lower far end of the firebox, its free and clear.

Theres an obvious problem with the makeup air intakes upstairs, one terminates under a piano with 1 inch clearance max, the other looks like its underneath fitted carpet, I cannot find it, I will make some measurements from the walls to better locate it. My inclination is to locate and cut the rug so its can breathe.

I removed the air filters from the squirrel fan box when I first looked at it.

We don't have any wood to burn yet, are these furnaces so inefficient just burning oil ?.

The exhaust pipe going into the chimney was very very hot.

https://youtu.be/OTtAUHxEe70?si=PNeuZsdpSu5UxVZQ

jonesg

i reinstalled all the panels on the furnace.

We closed some registers on the second floor to force air out of the vents on the ground floor.

i believe air flow is enough.

do you think it just needs wood to generate sufficient heat ?

I think we should try it.?

jonesg

https://forum.heatinghelp.com/discussion/comment/1810565#Comment_1810565

as you can see in this next video there are 2 controllers, one has black and red wires.

The other has green and yellow.

All the 4 wires go to a box on the furnace, some (yellow)? wires go to the oil burner and other wires go to an automatic flue control on the lower burner box door, the ash door.

the filters are removed , they were damaged/warped and will be renewed if this thing runs. i think the filters are from 2010.

I have some wood in the box now, is it possible to know which thermostat is which based on the wire colors.?

https://youtu.be/VrRH3zLaRcc?si=mN66nOhBhmsCIinV

jonesg

its a win, we fed it wood and fired it up.

heat is at the vents.

i told her to call the service guy before ordering oil, the farmer next door will deliver wood for $300 cord.

thanks for the help.

leonz

Here is the manual for that beast. You will be able to take care of here furnace now.

If that burner is original she will want to replace it sometime.

Longwood Furnace Series VII Manual.pdf

jonesg

thanks, she printed it out and put it in a plastic cover, its hanging next to the furnace .

service guy is gonna come out and do his thing, its up to her whether she wants to use the oil burner, I would just light it myself like any other wood burner, she is going to have to remove the ashes anyway.

leonz

Hello JonesG,

Did you cut the rug to open the cool air return duct?

Grallert

One concern I have. Does the fan stay on with the fire burning? If that fan switch (the protruding thing in the furnace plenum) senses a high temp it will open the oil burner circuit. this will short cycle the burner. There are setting under the cover on the outside of the plenum. With a wood fire it's important that the fan stays running to keep the heat exchanger at a safe temperature.

leonz

The furnace fan should only run when there is a call for heat.

Jamie Hall

I agree with @Grallert , and this all underscores a major concern I have regarding wood burning furnaces or boilers — and stoves — or, for that matter, coal burning ones, although it is less of a problem with them.

They will, sooner or later, run away. In my humble opinion — and I heated with wood for some time, years ago — any wood burning stove, furnace, or boiler, needs to have some facility to handle a runaway safely. For a boiler, that will include a dump zone which does not need electricity or operator supervision to activate. For a furnace, it means the main fan runs at all times that there is heat in the firebox (not just a visible flame, but heat). For both, and for stoves, it means that there is a way to kill the draught to the fire completely; for units operating without continuous supervision that has to be fail closed and automatic (fusible link and gravity damper on the inlet, or sometime of the sort).

To go back to the furnace. The old time gravity hot air furnaces had, of course, no fan. For those it was quite sufficient to provide a means for closing the draught on an overtemp condition in the bonnet or the stack — almost always a fusible link and a gravity damper. For units which depend on a fan for cooling the heat exchanger, you have a problem: if the power is out the fan won't run, of course. On those what I would want to see was an arrangement where electricity was required to hold the inlet draught damper open, as well as a high temperature switch which would run the fan on high when the bonnet temperature was over some convenient value — say around 200 F or so — regardless of a call for heat.

Is all this overkill? I think not. The old timers who did heat with wood were not fools, and they would either have such safety arrangements — or simply never run the appliance without supervision. Or both. If they hadn't had a runaway or chimney fire themselves. one of their neighbours had… and there were no fire departments handy by to save them. Folly was not an option.

Grallert

https://forum.heatinghelp.com/discussion/comment/1811000#Comment_1811000

It'd pretty common for these solid fuel appliances to over heat the space opening the call for heat while the fire is still up. I've seen too many run away. I'd like to see that circulation fan run to a cool safe chamber temperature..

jonesg

https://forum.heatinghelp.com/discussion/comment/1810893#Comment_1810893

there is 2 return ducts, I found one under a piano and moved the piano, the other was partially blocked by a bookcase, pulled the case out but I'm pretty sure she pushed the case back again.

I told her to call the local service guy so he could tell her, maybe then she will listen.

jonesg

I did open that plenum up and saw the fan switch , looked like a spiral bimetal heat sensor, coupled to the dial on the outside, it was free to move when i pressed the end of the spiral and the dial on the outside rotated,…. this was when cold obviously.

the circulation fan was running when i put some logs in it and fired it up, we had good airflow and heat from the registers upstairs.

jonesg

it has an elec controlled damper on the ash door to control draft to the firebox.

I believe in the case of a power failure the damper closes but the ash door can be cracked open to keep a passive burn going. Seems fairly well thought out.

hot_rod

another thing to check is all the door or damper gaskets. Those get dried out and harden and will not seal adequately. That can cause enough air to enter and cause an overheat condition, even with the damper closed.

Frequent overheating can also warp the doors.

Look for the good gasket material that has a red silicone coating. It tends to seal better and last longer than just the plain white door gasket rope.