We are having problems with the heating system in our house -- it is
not heating the house adequately and hasn't done so since we moved in 3
months ago! The previous owners converted from an old oil system to gas
just before we bought the house and we now have steam in the old part
of the house and hydronic/baseboard in the newer part of the house, all
being run by one new gas boiler with a heat exchanger on it.
We asked the plumber to come over today and have a look at it since we
weren't getting enough heat. He said that there was sludge that had
built up in the steam system from the old pipes and that it had
destroyed one circulator. He claimed that he couldn't guarantee the
circulator since he was not responsible for the pipes that were in the
old part of the house that he had never worked on. I told him that that
was not acceptable since he had told me (before I bought the house,
when I asked him if it made sense to do more work and upgrade the
system further at that time, and he said absolutely not!) that it was
a brand new system which he was very proud of and which he told me
would be more than adequate
for our home. When I asked if he could prevent/limit this from
happening again (maybe flush the lines a few times?) he said that he
couldn't guarantee it and that he couldn't flush the lines in a steam
system (I don't understand that).
He left my house before I returned from work this evening and so I
didn't actually speak with him after he worked on the system today. He
did however mention to Jenny that we might have a more substantial
Right now, we have very little heat in many of the rooms/radiators in
the house and it is cold and I don't know why?
Any thoughts/comments/advice for me for when I speak with him
What brand and model is the boiler and heat exchanger you have? If there is
an exchanger, how do the steam and water system co-mingle? I would think
they'd have to be separated or you'd have steam in the water system.
Thoughts and advice? Yes, replace the heating system. You are probably
headed to more problems with some half assed setup.
I've never seen a single boiler that makes both steam and hot water heat,
but they may exist. Steam, typically, is run through iron pipe. Over time,
the pipe corrodes, builds up scale, rusts, etc. Yes, it may have produced a
lot of gunk that crapped up a circulator on the water side if they are
somehow connected. I have heard of flushing pipes with cleansing chemicals,
but I've also heard of horror stores from doing that.
Other possibilities are air in the system on the water side that is
cavitating the pump and/or just reducing the heat transfer. Since steam
does not need a circulator, that portion of the house should be warm.
If the heat exchanger is for the hydronic baseboard, I don't know how
sludge can be an issue since the water for the baseboard is seperate
from the boiler water. I had this set-up in my old house.
I had another house with a different set-up. I had a steam boiler with
hydronic baseboard in the basement. All I did was tap into the return
line for the boiler, ran a loop in the basement and put on a
Both of these set-ups required hooking up an aquastat to make sure that
when the baseboard calls for heat, the water is at least 180-190
also a few questions:
Where is the baseboard in your house? Basement, upstairs?
Does the steam part heat OK?
The heat exchanger is a tank with a coil in it and uses two circulators. One
circulator moves dirty boiler water through the coil in the tank and back,
that one would get clogged if there was to much sludge. The other circulator
moves the heat exchanger tank water through the heating pipes and back into
I had something different. I had a Weil Mclein steam boiler, that had a
spot to insert a coil to make hot water. The coil ( or heat exchanger)
is in direct contact with the boiler water. There was an inlet and an
outlet on this coil. Only this was not used for domestic hot water, it
was used for hydronic baseboard. We just attached a circulator, a
regulator valve for the water supply, and an aquastat. It was just one
circulator, not 2. so this is why I asked how sludge can be an issue
because the actual boiler water never comes in contact with baseboard
water in my set-up. But I have seen the setup you are describing in
That was why I was asking the OP where his domestic hot water was coming
from. What you describe is the domestic coil used as a heat loop, which is
fine if the loop is not to demanding. If the demand is great, that coil
couldn't produce enough hot water to heat the loop, which is where a side
arm tank comes in. Instead of a small coil sitting in the boiler, a large
coil sits in this auxiliary tank, with an aquastat controlling the temp in
You're not clear enough on the situation. If the boiler can make steam, that
part of the house should be warm. The heat exchanger has to tap the water
jacket of the boiler at a low point, so if there is sludge, it'll mess up
the circulator as the plumber said, also as others have said air in the line
will cause problems. Having wired a number of side arms off of steam
boilers, I'd have sooner replaced the steam side or installed two separate
Do you have an actual heat exchanger or did he run this heat off a hot water
coil on the boiler? What makes your domestic hot water?
Is there a transferable warranty, the Sludge story is what my BSn
installer told me and is used by some to get replacement sales or could
be his way for an out. Steam lines wont sludge up but the bottom of the
boiler can. Is there air in the system, did you blead radiators, what is
the water temp and altitude. You probably need a different pro to go
over the whole system, it could be anything even an improper install.
Call the manufacturer of the system.
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