Posted by Paul on December 28, 2001 at 14:50:24:
In Reply to: Crane Sunnyday 5 boiler problems HELP posted by JC on December 25, 2001 at 15:44:38:
: I'm a homeowner and have VERY limited knowledge of boiler systems. My boiler is not keeping it's PSI high enough. There's no leak anywhere. It keeps dropping to 2.5. The city water won't keep the systems psi up. My friend, a boiler installer, has me hooking up the hose to give it make-up. I get the pressure up to 17, but it drops to 2.5 within 12 hours. It knows gives off a tea kettle pitch. This boiler was originally an oil unit, but has been changed to gas. I'm just throwing out info at this point. My house is cape cod w/ two rooms upstairs. I have to bleed air out up there periodically. Could it be the pump? I'm starting to feel that I need to replace this old boiler or put in a furnace with central air. This has ruined my family's Xmas. We were going to travel this morning but I thought we needed to stay and watch this system. Any thoughts?
Several thoughts. I've little experience with home heating boilers, mostly industrial and ship's. However here's my two cents.
If you are getting 17 psi on the boiler gauge the tea kettle sound is probably the safety blowing off. Check the tally plates on the boiler and the valve to see what your M.A.W.P. is. If it's 15 psi or lower, then it's likely your high pressure cut out not working or set wrong. If it is the safety opening up then that's where your water is going. As for air in your system, most likely you're putting it in with the city water. This is especially true if your make-up is cold. Use pre-heated water for make-up,saves on fuel and thermal shock as well. You can pre-heat with a small economiser, which can be as simple as a coil wrapped around your stack or a heat exchanger in your return. If you're having to vent your radiator traps a lot try installing some automatic bellows or disk type traps. You could also install a return trap by the boiler. Or if you're really ambitious and have the room an air seperating tank. All these things would have to comply with your local Codes as well because your local inspectors WILL insist on it.
Hope it helps.