Baseboard heat not heating house

Shawn70

I have a house with boiler and those baseboard heat with fins on 3/4 copper pipe.  When it gets around 20 degrees the first floor doesn't get warm with thermostat turned all the was up.  It there ANY fix that will keep house warm even at 20 below sometimes.   We have always had to turn on the oven and open the door when it's under 10 degrees which worked for 30 years.  I know it's not the best thing to do but nobody gave us a fix.

Any knowledgeable people are appreciated.  

Bigger boiler? Turn up boiler water temp? Replace all the original 40 year old baseboard fin sections with new? 

Is a forced air heat bill far cheaper than boiler & baseboard heat I heard 50% cheaper which seems incorrect. 

Please give me knowledge.  Looking for a HVAC genius. 

Thank you for your time everyone who replies. 

Shawn

mattmia2

With equal efficiency heating appliances, hydronic tends to be a bit mor efficient than forced air because forced air tends to increase infiltration.

your insufficient heat issue would require calculating the heat loss of the house then comparing it to the boiler. the downstairs could have an issue with zoning controls if it is zoned or a flow problem if it is not or the supply water temp set on the boiler could be low for some reason.

is it one or more than one zones? how is the 1st floor fed vs the 2nd floor that heats? does the boiler shut off on high limit during a heat call?

fentonc

The thermostat is just 'on' or 'off' - if the air temp is below the set point, it's on, otherwise it's off. Your house loses heat (measured in BTUs) proportional to the difference between the inside temp and outside temp. It sounds like with your current setup, if the boiler runs non-stop the baseboards no longer give off enough BTUs to match the heat loss when the outside temp is below 20F. The baseboards just give off heat based on their temperature difference vs the inside air temp - if they are clean and air can flow through them, the hotter they are the more heat they will give off, so you might be able to increase the water temperature at the boiler to allow them to provide more heat. If they are dirty (clogged with dust, pet hair, etc. so air can't flow well), you could try cleaning them so that more air can flow. Similarly, if they are blocked by curtains, furniture, carpet, etc. you can try unblocking them to allow more air flow. If the water is already as hot as it can get, and nothing is blocking them, you might just need additional baseboard (the heat is just proportional to how long they are - how many feet of baseboard do you have in the 1st floor vs 2nd floor?), or to reduce the heat loss through better insulation, air sealing, etc.

Hot_water_fan

We have always had to turn on the oven and open the door when it's under 10 degrees which worked for 30 years. 

Do not do that. 

pecmsg

Shawn70 said:

I have a house with boiler and those baseboard heat with fins on 3/4 copper pipe.  When it gets around 20 degrees the first floor doesn't get warm with thermostat turned all the was up.  It there ANY fix that will keep house warm even at 20 below sometimes.   We have always had to turn on the oven and open the door when it's under 10 degrees which worked for 30 years.  I know it's not the best thing to do but nobody gave us a fix.

Any knowledgeable people are appreciated.  

Bigger boiler? Turn up boiler water temp? Replace all the original 40 year old baseboard fin sections with new? 

Is a forced air heat bill far cheaper than boiler & baseboard heat I heard 50% cheaper which seems incorrect. 

Please give me knowledge.  Looking for a HVAC genius. 

Thank you for your time everyone who replies. 

Shawn

With the limited information no way of telling.
Turning the t-stat all the way up does nothing.
WAG a bad circulator and/or Air Bound!
Not enough emitters.

Get a home energy audit performed and find out where the heat is going.

I strongly advise NOT using the oven to supplement the heat. It's not designed for that!

hot_rod

If it has never kept up it is undersized or maybe mis piped. Increasing temperature or increasing flow rate may be enough.

A heatload calc would determine what is needed, then measure the amount of fin tube.

Rarely were boiler’s undersized back in the day. Unless the house size increased over the years.

Ironman

More boiler won’t compensate for under-sized baseboards. The boiler makes the heat, the baseboards emit it. If the current baseboards can only emit 1/2 what the boiler produces, what good would it do to increase the size of the boiler?

Make sure baseboard fins are clean, the dampers are open, and the bottom has an open path for air to be drawn in.

What type and model of boiler do you have? Some of them have Out Door Reset which adjusts the water temperature based upon the outdoor temperature. The ODR curve can be adjusted if needed.

Pics would be helpful, including one of the baseboard with the cover removed.

neilc

how many zones/thermostats ?
can you post a general picture of the boiler, circulator, and pipes floor to ceiling, all in one shot,
also a shot of a rad on the cold floor,

EdTheHeaterMan

85% of the heating capacity of baseboard heat is the convection air currents passing thru the enclosure.

There was one customer that would call me every other winter of so. Seems that during unusually cold spells, the heater could not keep up. This did not happen every year but only during extreme cold. It turns out that they paid for a minimum fee service call to find out the boiler was operating properly and the boiler was cycling by the high limit. Further investigation revealed the wall to wall carpet was installed under the baseboard, chocking off all but 1/4" of the bottom air inlet of the baseboard radiator.

I got the same service call a few years later and did not realize it was the same place until i got there. They paid the minimum service call fee to get the same answer as the last time. Get rid of the blockage or raise the radiators. I gave them an estimate for raising about 85 feet of radiators and of course they declined. Too expensive.

A few years later, my son got the same call again. They had to pay the minimum fee for the same diagnosis. I instructed my son to copy and paste the same 3 year old quote from the previous call and add 10% and give them the same response and collect for the minimum service call fee. (we were using I pads by then and the job history was available to each mechanic)

Moral of this story... Check to see if your baseboard convectors (aluminum fins) are blocked with anything like carper or dust or the damper being closed.