2 Pipe low pressure residential steam boiler

Bob C._2

Radiators with steam traps

house wont go above 65 degrees

Contractor says we need a high pressure flush and chemical treatment

boiler is set at 4 lbs

what are your thoughts?

STEVEusaPA

Pressure way too hi.

Can't comment if the only thing you need is a flush.

Paul48

4lbs

way....Way too high.

Bob C._2

Residential steam boiler

what are effects of to high of pressure? can it cause traps to malfunction

nicholas bonham-carter

Effect of over- pressure on traps

If your lucky, the effect of pressure above 2psi will only be the temporary malfunction of traps. If the pressure has spiked up above 4 psi, then they can be paperweights.

Often, the pressure has been set too high to overcome some venting difficulty in the system, and this only makes the situation worse. Verify your pressure is below 1.5 psi with a 0-3 psi gauge (gaugestore.com).

As far as "chemical flushing", one manufacturer recommends using arm&hammer washing soda, before a good skimming, which you can do yourself.--nbc

Jamie Hall

I'm sorry to say this...

but the contractor who recommended a high pressure flush and chemical cleaning either hasn't a clue, or is trying to drum up more business to fix the damage caused.  I'd much rather think that he or she was simply clueless.



One -- as every one has said, crank that pressure down.  Two pounds max. for the cutout.  And hope that any vents and traps recover from the high pressure; they will all need to be checked out.  You ask what can happen with higher pressure: if you're very fortunate, the heating system simply won't work until the pressure is lowered.  If you're less fortunate, you will have to replace every single one of them as they will have been destroyed.  You will have to wait and see on that.



And chemical flushing is almost never required.  As NBC noted, sometimes you might try baking soda and water, but unless this is a new install even that shouldn't be required.  If the water level is bouncing a lot, you might need to skim.



There are several reasons the building won't go above 65.  You don't mention how long the boiler runs at a time.  However, the two most likely suspects at this point are the high pressure -- fix that first -- as it may have locked the traps and vents shut, and if the air can't get out the steam can't get in; no heat.  A symptom of that would be the boiler cycling on and off on pressure with no heat.  The second suspect is that... the boiler isn't big enough, or you simply don't have enough radiation in the building.  But I would assume that that has been checked.

LarryC

Buy Dan's books.

Bob,

Dan Holohan is the website owner.  Buy Dan's book "we got steam heat".  It is a nice primer about steam heating systems and what you should and should not do to take care of your heating system.  The cost of the book(s) will be paid back in one service call.

The steam pressure should be as low as possible, the main air vents should be as large as necessary, the radiators should be heating up within a few minutes of the burner firing, the system should have no banging, the water in the sightglass should not be bouncing around when the system is running, and the furnace should cycle maybe twice an hour depending on house construction, insulation levels, outside temperature, etc.

Go up on the website to the "Find a Professional" to find a qualified service person in your area.  With the price of fuel, it is expensive to have an inefficient heating system.



Good Luck.