Land Rover Forums - Land Rover Enthusiast Forum - Need quick help with home heating system!

I'm quickly becoming familiar with a natural gas fired boiler hot water heater system of my mothers home...

Short background, the pilot light went out on the boiler, she called a plumber friend of a friend of a friend twice removed or some ****, and he came over and fixed whatever the issue was. He warned her that the system is very old (1950s, even though most of the parts have been replaced within the last 5 years with modern components other then the boiler furnace itself) and is on its last legs, and might need complete replacement soon. (first alarm ring bells for me)

2 days later, she calls and tells me the water pump is ratteling like mad. (pump was just replaced 3 years ago maybe? think by the same guy.) I go look at it, and put oil in it... every month or so it needs a few drops to quiet down, seems to weep out the bottom of the pump, she never had it addressed. looks like there should be a gasket there, but waht do i know.

anyway, i also notice the bucked under the pump where the oil was dripping has a good 2 inches of water in it! then i notice the oil leak is now dripping to the point where about 2 hours later (instead of ~3 weeks) needed refill. I also noticed alot of steam comming out and wet look around some pipe seems. I also see water dripping out of the pressure relief valve.

I look at the boiler pressure, and its at 30psi. i look at the temp setting on the boiler and its a hair under 210.

I dont know what these should be, I have no experience in home heating... but im a pump operator for the fire department so i'm somewhat familiar with hydro systems etc.

A quick google yields that normal pressures for this sized house (1 storey ranch btw) should be around 15psi, 20psi maybe slightly hiring while boiler is on heaat cycle. and the temp should NEVER exceed 210 degrees or 30psi when the relief valve would open.

i immediatly lower the temp to 170 on the dial and the pressure drops to around 26psi on teh guage... the water leak, oil leak and rattling have stopped.

now, according to the internets, this pressure is still to high for comfort, but i cant figure out how to open the system to let that pressure drop.

there are two valves next to the water pump that have handles, one i have identified via the net as the over pressure relief valve (which was dripping when the pressure was 30psi) which has a throw switch on it. horizontal i believe is off, stright up is a bypass to fill the boiler at home water pressure, wahtever that is (40-70psi ive read but never measure from a hose outlet as recommended). the other one has an arm on it that if pulled, sprays water out of the bottom into the bucket...

so, should i hold that open to drain water to lower the pressure, or is that just some sort of drain bypass to empty the system for service... or something else entirely?

i also came across a site that says to check the expansion tank to see if its water logged, and if it has air pressure. the tank looks brand new, but does not look like most of the pics/videos ive seen online. one website said there are two types of expansion tanks, one being called a pressure tank and only says it is tested differently then a horizontal bladder one. this tank is 4 feet or so higher then the two valves by the water pump, and is verticle with the water pipe going to the top of it, and a blue plastic cap on a bottom valve which i assume is where i would check its pressure.

any advice here would be great short term... i lowered the boiler temp setting and the pressures steady at the moment never exceeding 26psi and no more leaks, but id like to get that down while i find a new plumber. i think this guy was setting us up for failure to get work out of her!!