October 28, 2004 Greg and I troubleshoot his hot water heating system.
Q. Hi Bob,
My furnace pressure relief valve goes off
on a daily basis. It is a 30 lb pressure
relief valve. I wonder if the valve is too
small or there is air in the system. The
water pressure regulator is 15-18 lbs.
What is the proper water pressure that should
be maintained in the system? How big is the
proper pressure relief valve? I tried to
bleed the system to purge the air out but
it doesn't work. This furnace is only used
to heat one 3 bedroom apartment and a basement.
Thanks a lot!
Greg
A.
Greg,
30 lbs. is ok.
Water pressure regulator at 15-18 lbs., that's not a problem, that's normal.
I think your relief valve should be replaced, they wear out under the heat.
Try that first, let me know. Bob
Q.
Bob, Thanks for your response. The relief valve was just
replaced last year. Should I replace it again? Should
I go for a larger one like 50 lbs? Thanks,
Greg
October 29, 2004 A.
Greg,
It could be a defective relief valve. I would try replacing it. Stay with
the 30 lbs., don't go larger.
Bob
October 30, 2004 Q.
Bob,
When I was ready to replace the relief valve I noticed
that the valve was working the way it was supposed to.
It was the system pressure that was too high. I
noticed that the valve started to release water when
the pressure gauge was at 32 lbs. Is it that the air
is still trapped in the system? How can I get rid of
it? I don't see any air valves near any radiators,
they are baseboard radiators. There is an air relief
valve sitting on top of air scoop on top of the
furnace, but it didn't do anything because it sat too
low. Is there anything else I can do?
As always, thank you for your help.
Greg
October 30, 2004 A.
Greg,
There should be a bleeder valve on the return line going back to the boiler.
The return line goes into the bottom of the boiler. There should be a
shut-off just before it enters the boiler. The bleeder valve will be before
the shut-off and will look like a hose bib, (faucet). You'll hook a hose on
to it; close the shut-off valve (so you don't drain the boiler) and leave
the cold water supply open (going into the top of the boiler). Open the
bleeder valve (with a hose on it or a bucket under it) until you get water
flowing with no air.
Try that, let me know. Bob
PS: And Greg,
If it's not air in the lines, it could be your pressure reducing valve that
is on the cold water side as it enters the boiler(furnace) it lowers the
house pressure to + - 30. The strainer on the valve could be dirty, causing
the valve to stay in the open position.
October 30, 2004 Q.
Bob,
I bled the system, didn't notice any air coming out.
As soon as I turned up the thermostat, furnace fired
up and circulator running, I noticed that the pressure
started to go up, when it reached 32-33 lbs and water
temperature 200 F the relief valve started dripping
water. The pressure stayed at 32-33 lbs until the
flame was off. After the fire was off but circulator
was running, the pressure started to go down until it
was at 18 lbs
When furnace is in off position and circulator not
running, the pressure stays at 15 lbs. It seems to
indicate that the pressure reducer is working.
Besides, the pressure reducer was also replaced last
year together with the relief valve.
What else I need to look at?
Thanks,
Greg
October 31, 2004 A.
Greg,
Try lowering the boiler thermostat so that the water temperature does not
exceed 150. The control should be near the burner; lower it.
Bob
October 31, 2004 Q.
Bob,
I lowered water temperature to 180, the lowerest
number on the dial, it was set at 190 degree. It is an
Honeywell control, no idea how old it is. But the
pressure goes up so quickly that it's already reached
32lbs when the water temperature is only 45 -50
degree.
The water temperature stays at 40 when the furnace is
off.The water temperature stays at 40 because it is warm
today, the furnace has been off
Greg
A.
Next question: Is there an expansion tank above the boiler. A smaller tank
that usually hangs from the ceiling or is on a platform? Bob
October 31, 2004 Q.
Bob,
Yes, there is an expansion tank which was also
replaced last year, the circulator was replaced two
years ago.
Greg
November 1, 2004 A. Greg
It sounds like you had a lot of work done on the heating system last year.
Try purging the expansion tank. It may be full and there is no room for
expansion. There may be a drain valve at the bottom of the tank. If not
you'll need to empty the boiler enough for the tank to drain. (Turn off the
furnace and close the shut-off valves, in any case.)
I've been able to tap on the tank with a small hammer to hear if the tank is
full of water or empty. Bob
November 2, 2004 Q.
Bob,
We did it. It was the expansion tank, not only was it
filled with water, there was no air in the tank at
all. I drained the tank and pumped 15 lbs of air into
it( is it too much? the factory pre-filled air was
only 12 psi according to the label). The pressure
never went above 22 lbs in the system. The only thing
is that the water temperature is still around 200
degree.
Yes, I was trying to exclude all possibilities. It is
an old system, looks original. I believe the house was
built in 1968-1969, so the system is about 35 years
old, probably at the end of its life span. Thank you so much for your help. I learned a lot form
it. Greg
Greg writes back with another question:
Q.
Bob, Another interesting thing is that there is another
temperature control that is attached to the copper
pipe coming out of the furnace. It says "temperature
control" on the label. There is a dial pointing to 180
degree. This box is connected to the temperature
control box where I made adjustment previously with a
single wire. If previously adjusted box is the
temperature control, then what is this box for? It
looks like it is taking a reading of the copper pipe
temperature that is coming out of the furnace. I
lowered the dial to 160 degree anyway but don't know
if it will do anything.
Greg
December 8, 2004
Q. Dear bob,
i have a washer that is about 10 years
old and it seems that if i need do
a full load of laundry my washing
machine will walk around on the floor.
What is wrong andhow can i fix it? it
just started doing this. thanks, dave
A.
Dave,
The washer is not leveled. Use a level on the top and side of the machine.
There are leveling screws at the bottom that can be adjusted. If they are
too rusty to unscrew, then use wood shims.
Bob
April 22, 2008
Q.Bob,
I just installed 2 new faucet kits, and both of them leak
at the threads
just under the sink bowl. I put plumbers putty, and even
used the rubber
gasket that was sent with the kits. I can't get them
to stop leaking. It
is not a very large leak, but a leak non the less. I took
he kits apart 3
or 4 times, and reapplied the plumbers putty, and the
rubber gasket. Any
suggestions?
Bob
A.
Bob,
You're talking about the basket strainer connection to
the sink. It's probably the putty; people don't install it correctly. Okay,
here goes:
How to install the plumber's putty on the basket strainer:
Take a big handful of putty and knead it like you would clay or playdough,to get it warm and flexible.Roll it into the diameter of a cigar. And make it long like a snake to wrap around the inside of you sink, and overlap. The putty goes between the sink
and the basket strainer (pop-up waste with the pop-up removed.)
Gently pat it to stay in place. It helps to have two people. One on the top side holding the basket strainer and one below tightening the large nut. Now carefully push the basket strainer onto the putty, squeezing the putty out the edges. DO NOT remove the putty until later. To hold the strain in place it helps to use the handles of a channel lock or pliers. You put the handles in the basket strainer and push them against the strainer, opening the pliers.
The beveled gasket goes against the hole in the sink, bevel side up. Begin slowly to tighten the nut, squeezing more putty out...then tighten the nut all the way, as much as you can, flattening the gasket.
Hook up the trap and test for leaks. If necessary, tighten the nut some more...a little more, gently...try again...a little more..until it stops leaking.
Gently remove the excess putty. Do not scrap all the visible putty out. It will be less visible as time passes.
Good luck and let me know how it goes,
Bob
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