furnace/boiler running constantly

it's very cold outside all of a sudden (-36C with wind chill) and the hot water boiler started running a lot to keep the house warm. how are the blowers designed? can they run constantly for certain periods of time without burning?
since it's just an inductance motor and the load is constant, I'd say it shouldn't burn out...
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
The furnace should run at 100% duty cycle with no problem. The blower's induction motor will handle this. If oil fired, it is relatively easy to change the orifice to a larger diameter to increase the firing rate which will mean that your furnace could turn off some at this temperature. Be careful to not exceed the firing rate specified though. I have mine set to run 100% of the time at -20 F and have verified that at 100% and -20F outside I am at 72F inside.
The most comfortable situation is when the blower runs all the time so don't over fire the system.
RB
j j wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Hi RB, hope you are having a nice day
On 08-Jan-04 At About 06:22:38, RB wrote to All Subject: Re: furnace/boiler running constantly
R> If oil fired, it is relatively easy to change the orifice to a larger R> diameter to increase the firing
I would not suggest anyone do this unless they have the proper equipment and knowledge to do so.
-=> HvacTech2 <=-
.. No one is born knowing all about this stuff...
___ TagDude 0.92+[DM] +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ spam protection measure, Please remove the 33 to send e-mail
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Heating systems are designed for a certain low temp. Go below that temp and you are out of the design envelope. Your system runs all the time and won't keep the house warm.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

what do you mean by "low temp" ? low temperature of what?
the system (oil-burning hot water heating with radiators) has 2 thermostats at the furnace: one is set for the water pump (water goes below a certain temperature and the pump stops) and one for the furnace/boiler (water goes above certain temp, furnace stops) the furnace thermo is set around 170F. previously the furnace would stop because the water would get hot enough. today the water doesn't get hot enough anymore and the furnace keeps running. before my room would go to 24C before the house thermostat (in the middle of the house) would stop the furnace, or the furnace itself stopped because it got too hot, now it runs all the time and barely keeps the room at 21C
I don't know if anything changed or if it's too cold all of a sudden...
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Low temp as in the lowest temp your area is supposed to have 98.5%(?) of the time. This temp has nothing to do with the setpoint of your heating system.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

oh no the temp outside is not *that* low, just cold all of a sudden the temperature where I live (montreal, quebec) can drop to -50 at night, with windchill tonight it's supposed to be -44C depending on the winter, -20C (-30 with wind) is common
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.