PROPER BOILER OPERATION????????
Hi guys,
We are going through some very cold weather in the northeast ( 5 to 15 degrees F.).
Not sure that my boiler is operating properly. Seems to operate well duing more moderate weather. May need to do some adjusting or fixing??
House is 70years old and uninsulated (I know that this is a need to do!). Approximately 2000 Square feet – two story.
Boiler: 3 year old hot water. 125, Btu
Has Amtrol/Extrol Model 30 expansion tank with air input valve at bottom.
When Operating:
Boiler temp. tops out at 120 degrees.
Boiler pressure 29 psi
Pressure relief valve 30psi
Amtrol/extrol expansion tank at 24 psi
Boiler turns on and off normally at current settings. Will not heat house to above 63 degrees. If temperature moderates a little bit it can take 6 to 7 hours to bring house temperature up to 70 degrees.
Radiators bled – heating completely.
If boilers upper limit (temp) is raised pressure relief valve opens.
Amtrol/Extrol expansion tank warmer at upper half with a solid sound if tapped on.
Lower half sounds hollow.
QUESTION: Does expansion tank need to be serviced (air added) or replaced??
If expansion tank needs to be replaced can this be done with out
draining the entire system??
I realize that the weather is placing some real stress on the heating system. But
I would still appreciate any direction or comments that you might be able to provide
that would allow me to improve the heating situation.
Thanks,
Bob ( from verrrrrry cool Buffalo N.Y.) (not much snow)
Replies
From what you write, boiler pressure is too high ( around the philly area, most are 'run' at 15 psi) let some water out to reduce pressure. if the pressure stays high. then the auto feed valve is set to high. On the front of the boiler there is a limit for boiler temp and this may be set to 125. Depending on your type of heat radiator (iron, copper, steel, in floor etc.) this might be correct. Check with local service guy.
With the extremes we're going through you might not have enought heat capacity from the boiler to make up for the heat loss. Best bottom line is to insulate where you can. I suggest start by checking for drafts and seal where you can. Attics are the easiest and quickest is blown cel. or fiber glass. (rent from Lowes for DIY or better still hire pro crew).
Pressure is to HIGH!. Most relief valves are set at 30 psi. When water is heated it expands and pressure rises if expansion tank cannot absorb the espansion. Bleed down to 12-15 psi, Reset temperature of boiler to 170-180. If valve continues to blow check air tank for a water logged or leaking bladder.
Insulate!! At 125MBH your boiler may be undersized for an "uninsulated" 2000 sf house.