
Ask HN: What to do with an existing hydronic house heating system? - EFFALO
Just moved into an older house that has an existing hydronic baseboard heating system installed. It&#x27;s connected to a boiler that burns heating oil. While the system is quite old, it still works. I&#x27;ve never lived in a house with this type of heating, but from my research I&#x27;ve learned how expensive and inefficient heating oil is, compared to more modern methods of environmental control.<p>Does anyone out there have any suggestions or experience on how this system can be repurposed to be made more efficient? Given that all this pipe has already been run, I&#x27;d prefer to find a way to put it to use over removing it entirely.
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brudgers
_my research I 've learned how expensive and inefficient heating oil is_

Test and measure.

The most common (in the US) type of home heating systems are forced-air. Fans
pull cooler air into the system, past a heating element, and then out into the
space to be heated. The heated air eventually warms the occupants by
convection.

The less common (in the US) approach is radiant heating. Heat up a surface and
warm the contents of the space (including people) by infra-red radiation. This
is how most of the heat in the universe moves (e.g. the sun's heat across the
vacuum of space to the earth).

Hydronic heating via baseboards has several potential efficiency advantages.
It is radiant. Radiant heat heats people not air. The transfer mechanism is
liquid not air. Water conducts heat more efficiently than air. This is why
fiberglass insulation is fluffy full of airspaces and why it loses
effectiveness when wet. Finally, radiant baseboard provide heat along the
building perimiter, low-near the floor, and without creating drafts (moving
air).

Fuel-oil prices tend to fluctuate more than electricity or natural gas because
it is less subject to regulation. It is less subject to regulation because
natural gas and electricity run infrastructure in the public right of way.

Finally, expensive is relative. That's why test and measure. Fuel oil can be
twice as expensive as natural gas. But that might mean $600/month versus
$300/month or $150/month versus $75/month. Those are economically divergent
against the cost of changing the system.

Ok, the real "finally." If it ain't broke don't fix it. Having a warm house is
98% of what's important. There are lots of other places to spend money that
will significantly improve livability. Many of them are going to be easier to
accomplish because swapping out heat systems involves lots and lots and lots
of tradeoffs, vetting contractors, and living with disruption of significant
construction...and of course, swapping out heating systems doesn't make your
house better. The fact that the system is still in use is evidence that it is
good enough. Good luck.

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tucaz
This is the reason I come to HN. Thank you, sir.

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PaulHoule
What I've heard is the opposite. If you are going to burn fossil fuels for
heat, those oil burning boilers are more efficient than most hot water heaters
and furnaces. The hydronic system is also efficient at getting heat in the
right place.

To really improve on an oil boiler, you could get a heat pump or maybe active
or passive solar. If you have a system that generates hot water you could
probably run it through existing pipes.

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brudgers
Most places with boilers are too cold for air to air heat pumps to be viable
during heating season. Geo-thermal heat pumps have a wider range but they
involve significant site work and require a non-trivial lot size. In terms of
expense a typical geothermal heat pump will have a very long payback period.
An open loop geothermal heat pump might be practical if there’s a source and
sink for the water running through it. Most people don’t have those. But it’s
a simple system with a water pump and fan as the only moving parts.

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toomuchtodo
Air source heat pumps can operate all the way down to 0F. I’ve paired one with
a hydronic system, with a firewood heated boiler for backup heat, in rural
Pennsylvania.

The less reliable power is and the colder it gets during winter months, the
more tricky the problem gets.

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brudgers
Typical residential units come with a resistance electrical heating element.
It forms the basis of the "emergency heat" functionality. It also begins
operating as ambient outdoor conditions exceed the performance of the heat
pump mechanism.

I mention this not because this is what your particular system does. I mention
it because it is typical for widely available residential heat pumps in the
ordinary market.

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one2know
Someone told me they switched to heating oil because the local market had only
one local utility for natural gas which was charging too much. With heating
oil there are multiple suppliers who can drive a truck to your house and price
competition.

All heaters are 100% efficient in that any leaked heat leaks into the house
you are trying to heat. I would look at insulation if you are trying to be
more green.

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seattle_spring
My hydronic system is heated by a tankless and costs almost nothing. Would
that be a possible conversion?

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gshdg
My cousins use a black roof with water pipes just underneath to absorb heat on
sunny days, and circulate it down to a giant insulated basement water tank
that functions as a heat sink. They then use that to supplement their heating
system.

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sloaken
Fill your oil tank now while prices are low. If you can get the company to let
you pre-buy at todays prices, I would do that too.

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dhruvkar
In addition to all the other comments, radiant heat doesn't dry out your skin
like forced air does.

This was a big plus for me.

