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Furnace problems please help

bender1227bender1227 Member Posts: 31
I just had my Weil Mclain CGT furnace cleaned of all the carbon build up and after the unit was serviced it is taking forever for the heat in my house to rise to the level I want it to. Before I had the unit cleaned I had no issues but now it is taking hours to raise the temperature in my house a degree two. What could the issue be? My house is at 66 degrees but I can't get it up to 70 degrees.



  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 6,927
    What's your outside temp? Are you in this Polar Vortex?

    Did the technician do a combustion test. post the results and some pictures. We need more information to respond
  • bender1227bender1227 Member Posts: 31
    Yeah I live in NJ and it's 1 degrees outside, but I don't recall this ever happening with my heat.
  • bender1227bender1227 Member Posts: 31
  • JellisJellis Member Posts: 199
    Is the unit running basically non stop? or is it shutting off for any amount of time?
    There are many possibilities that could be causing this issue.
  • LanceLance Member Posts: 142
    Your boiler is up to temp at a setpoint based on?? Temperature has a direct correlation to radiation output. Most homes in NJ could be sized for the coldest day of 10F. to maintain 70F inside. If temps go below design temp, it will make a corresponding drop in indoor temp. One could raise the boiler hi limit to maintain 190F. A most common design temp for radiation sending calculated btus to the space they are in. Also you could have a mechanical problem with water flow, of which they are many causes there. Old codes used to use 240F as the highest limit. This provides a lot of heat using lessor radiation Sq Ft.
    Alas, many boilers today wont let us go that high. Instead if enough btus are made we may need more flow and more radiation to meet our thermal comfort needs. Time to put a sweater on the house. ;-)
    I believe your boiler uses indoor air brought in from the outside via the room to make heat. Another cold load to bear. Using direct outdoor air for combustion can save up to 17% over the heat season. Now would be a good time to measure return water temps from each zone. Anything over 20-25F difference from the supply temp could need attention. If normal, might suggest not enough heat removed from the radiation into the room.
    My house is sized perfectly. For a 15F coldest temp. My room temps drop by degree each degree below 15F. And when the wind blows, Bwrrr! Got to seal my air leaks.
  • pecmsgpecmsg Member Posts: 1,387
    The NE is at or below Design conditions with High winds. Everything is maxed. Probably nothing wrong. Let it run as it gets warmer today you'll see the inside temp come up.

    It may acutely be a good sign, it means the equipment is sized properly!
  • bender1227bender1227 Member Posts: 31
    Okay, I'm going to wait a few days and see what happens.
  • billtheplmbr3845billtheplmbr3845 Member Posts: 41
    Check the water temp near the zone valves, it could be the three way mixing valve not opening properly. If the actuator is not pushing the plunger down you may get your symptoms
  • VoyagerVoyager Member Posts: 229
    Was the system bled properly? Are all three zones equally cool?
  • bender1227bender1227 Member Posts: 31
    The issue is still happening. When I turn on a specific zone the pipes in that zone right past the zone valve gets hot.

    I believe I bled the zones correctly. What I did was turn on one zone and bled it until I didn't hear any more air coming out.

    Could it be that the water temp max needs to be raised? On the side of the furnace, it says the max water temp is 250 degrees and the gauge is fluctuating between 160 and 180 degrees?

  • Jamie HallJamie Hall Member Posts: 12,696
    Raising the water temperature isn't going to help. 180 should be ample. If the hot water isn't getting into the zone, making it hotter isn't the cure, is it? For some reason which you haven't found yet the water isn't moving through that zone. It could still be air bound. It would appear the zone valve is opening, so it's probably not that. Any other valves on that zone?
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • bender1227bender1227 Member Posts: 31
    I just checked the different zones and all the valves are open and the water leaving the system is just as hot as the water returning as I felt the pipe. I can also hear the circulator pumping pushing running.
  • DZoroDZoro Member Posts: 1,035
    Are all the radiators hot? At 180* you shouldn't be able to grab and hold on to them very long...
  • billtheplmbr3845billtheplmbr3845 Member Posts: 41
    Did you check the three way mixing valve, if stuck it won't let water flow in the zones
  • woodrowwoodrow Member Posts: 32
    is it baseboard or free standing radiators may need to bleed rads
  • bender1227bender1227 Member Posts: 31
    They are baseboards and they are very hot to where I can't hold on to them for long throughout the house. I believe the circulator pump is working because the pipes are hot leaving the furnace and coming back in. When I bled the different zones I must have taken out at different intervals 30 gallons of water making sure there wasn't any air left and I didn't hear any. Could I have bleed the lines wrong?

    Would the mixing valve be working if all the pipes are hot?

    How do you bleed the line. I just use a bucket and let the water run out till I stop hearing air coming out for each zone.
  • DZoroDZoro Member Posts: 1,035
    Sounds like the boiler side is doing its job. If you have a digital thermostat make sure you have good batteries in it. No programs or any set backs. Leave system on one temperature, at least in very cold situations. With radiant I wouldn't recommend any turn downs.
  • JellisJellis Member Posts: 199
    If your baseboard is so hot you can barely hold it for than a couple seconds then it sounds like your system is "working"
    do you hear "rushing water" in the baseboard? that would mean you did not purge correctly and have air in the lines, which would cause zones not to heat to their full potential.

    If you have no air in the line, and your thermostat is calling for heat, your zone valve should open and your pump should come on.
    If all of these things happen and you still have the issue.
    What are your aquastat settings?
  • bender1227bender1227 Member Posts: 31
    My Aquastat is set at 185 and the lines don't seem to have any air in them as they are hot all around the house. I just moved the aquastat up to 185 from 180 and the system seems to be working better. I'm going to give it a few days and see if I am still having the issue.
  • DZoroDZoro Member Posts: 1,035
    Vacuum, clean, straighten all the fins, make sure it is clear and open on both the bottom and top of the baseboard.
  • JellisJellis Member Posts: 199
    Good thinking to turn up your aquastat. Sounds like your system is designed pretty close to the design temp. I think its a great idea to install a secondary heat source for these really cold days. I often see gas heaters or wood stoves installed in basements and used for this purpose.
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