burner cycles for small room

Abro

realolman

small room burner cycles

I have two zones in my house , each with a circ pump: one for the house and one for a 12 X 12 room that is well insulated, but mostly glass windows, ...a sunporch.

I have been logging the pump runs and burner runs, and have them attatched. The green is the pump for the whole house and the blue is for the small room. the red is the oil burner. The blue line is the outdoor temperature.

I have just installed a becket heat manager which changed the differential from 10 degrees to 23.... believe it or not, it used to be worse.

I have delta T's of 37 for the house and 29 for the sunporch.


I have setback thermometers on both zones, but right now the sunporch is just set at 60, and does not change. When a thermostat calls for heat, it runs the pump, and would start the boiler, except for the heat manager, or if it was already above high limit (180)


Is there some way I could cause fewer burner runs other than boarding up the windows?

scott markle_2

hydraulic separator

Buffer tanks can also provide nice primary/secondary separation. Is the current system piped P/S? If not wonder if P/S alone (no tank) would effect cycling. On the small zone perhaps a (fixed temp) mixing valve would help even things out,obviously as evidenced by the chart the water to this zone is hotter than it needs to be, have you tried closing the shutters on the baseboard?

scott markle_2

opps

heatboy_2

Relays

Does each pump have a dedicated relay? If so, could you just disconnect the boiler enable circuit on the sunroom? Longer pump cycles without the burner running could be the result. IF your boiler has a little mass to it, it would surely run longer and more efficiently when the main zone calls for the burner to run.

realolman

thanks

these are all good and I appreciate them.

I hadn't thought of disconnecting the burner from the relay. I'll have to think on that, as it would be the easiest, cheapest, and certainly effective in cutting down burner runs. I wonder if therre would be any down side to that.

I also thought of mixing the water temp down... I'm not sure what to do. No, it is not primary secondary. It does heat the room fast, but it also has a pretty good dT.

I have another chart showing boiler temps etc. the boiler hight limit is 180+ because that is where the beckett heat manager said to set it, and then it lowers the differential.


If you care to look at the attachment, the two heavy lines down around 70 degrees are the two circ pumps ... blue is the sunporch and green is the rest of the house. Red is boiler temp. Thin green and blue lines are zone return temps. Purple line is stack temp.

This is during a recovery period from about an 8° setback in the house. The sunporch stays at 60. The black is outdoor temp.


Again ...thanks these are excelent suggestions, and I appreciate it.