Shorter heating cycle after domestic coil replacement
#1
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Shorter heating cycle after domestic coil replacement
Hi all, first post.
We have a Weil McClain oil furnace with baseboard hot water and 3 hydronic toe kick units. We had the domestic coil replaced recently as it was corroded and flaking rust.
After this was done our heating cycles are a little closer together - used to be every 30 - 32 minutes heat would fire up, now around 23 - 26 minutes (same average temps outside).
Also notice two other things:
1) Circulating pump comes on and runs roughly 40 seconds before the burner does. These two used to come on together. We had the same behavior 2 years ago when there were issues with the original install and air in the system.
2) The basement is warmer than it was before the repair, which leads me to believe that less heat is going upstairs than before.
I was right there watching the service tech remove and reinstall the coil. It went (thankfully) uneventful. The system was purged of air after the install and there are no telltale signs of air in the system.
Other than the coil, nothing has changed in the system. The one thing that the tech did do was adjust the pressure of the auto water feed valve, so maybe that has something to do with the new behavior?
TIA,
JP
We have a Weil McClain oil furnace with baseboard hot water and 3 hydronic toe kick units. We had the domestic coil replaced recently as it was corroded and flaking rust.
After this was done our heating cycles are a little closer together - used to be every 30 - 32 minutes heat would fire up, now around 23 - 26 minutes (same average temps outside).
Also notice two other things:
1) Circulating pump comes on and runs roughly 40 seconds before the burner does. These two used to come on together. We had the same behavior 2 years ago when there were issues with the original install and air in the system.
2) The basement is warmer than it was before the repair, which leads me to believe that less heat is going upstairs than before.
I was right there watching the service tech remove and reinstall the coil. It went (thankfully) uneventful. The system was purged of air after the install and there are no telltale signs of air in the system.
Other than the coil, nothing has changed in the system. The one thing that the tech did do was adjust the pressure of the auto water feed valve, so maybe that has something to do with the new behavior?
TIA,
JP
#2
Sounds odd to me.
What is the model # of the boiler?
What are the settings in the aquastat? Hi/Lo/Diff?
What does the pressure and temp say on the boiler gauge?
Once we get that info we can move forward.....
What is the model # of the boiler?
What are the settings in the aquastat? Hi/Lo/Diff?
What does the pressure and temp say on the boiler gauge?
Once we get that info we can move forward.....
#5
After this was done our heating cycles are a little closer together - used to be every 30 - 32 minutes heat would fire up, now around 23 - 26 minutes (same average temps outside).
1) Circulating pump comes on and runs roughly 40 seconds before the burner does. These two used to come on together. We had the same behavior 2 years ago when there were issues with the original install and air in the system.
2) The basement is warmer than it was before the repair, which leads me to believe that less heat is going upstairs than before.
Pressure roughly 18 PSI
#6
temp on gauge shows around 200 degrees after running
Again, probably normal.
If there is a heat call and the boiler fires up to say 180° and the heat call ends, the burner will shut down and so will the pump.
With no further circulation in the system the heat that is in the cast iron of the boiler will then soak into the water and raise the temperature above the setpoint...
Normal behavior.
If on the other hand the burner does not shut off at 180° setpoint WHILE A HEAT CALL IS IN PROGRESS, then there may be an inaccuracy in the aquastat...
Wait for the boiler to cool down ... shut it off for an hour or two if you have to. Push the thermostat up to force a long heat call. Observe the temperature that the burner shuts down. It should be within 5-10 degrees of the setpoint.
Turn the thermostat back down again and observe the temperature in the boiler rising due to the 'heat soak' occurring after both the burner and the circulator shut off.
Let us know if you see different behavior.