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Speedy Jim
 
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Default Boiler Shuts Down

John F. wrote:
When the outside temps (I'm in upstate NY) get down to the teens and single
digits my boiler can't keep up with the heat loss. There is baseboard
cabinet (7 inch cabinet) running the entire perimeter of the first floor
exterior walls of the four rooms (each 13x13) the zone covers. The rooms
are 8' 9" and all walls are insulated to R-13. The windows are dbl
insulated glass and the basement ceiling below is insulated as well. The
heat pipes are also fully insulated in the basement. The boiler (oil fired
baseboard hot water 2 zone system) rated at 150,000 btu shuts down when it
reaches the 180 deg boiler/water temp. I've been told that the 180 deg is
the proper shut down. The thermostat calls for heat with a 2 degree drop in
temperature. Right now it only runs for about 10 minutes before it reaches
its 180 deg mark and then shuts down for about 15 mins. The result is a
net loss of room temperature especially at night of upwards of 6 to 8
degrees resulting in a room temp of 60 to 62 degrees by morning. If temps
go into the below zeros then the boiler never catrhches up even in the
daytime. So my question is what if anything can I do or have the oil
burner service company do to have the burner deliver heat for a longer
peiod. Your usual good input would be appreciated. Thanks. John


It doesn't sound like a burner/boiler problem to me.

If the boiler is easily maintaining ~180F, the problem
seems to be that the circ pump and radiation can't *remove*
enough BTU from the water.

For example: Although the boiler has a rating of 150,000BTU/Hr,
let's say that the rads can only unload 50,000BTU/Hr.
The burner would only need to run 1/3 the time .

But the house needs 100,000BTU/Hr in coldest weather (example).
The boiler *could* produce that easily, but the rads can't
pump the BTU's into the house fast enough. So...house gets cold.

You may have to have someone re-calculate the fin-tube area
required and/or the pump capacity to deliver enough water velocity.

Jim