New system, old house

Brad Barbeau

We're in the process of retrofitting a hot water heating system into our home and I'm hoping there may be some suggestions on here about how to proceed. We've decided with advice of some contractors to replace the existing forced air system with hot water. The house is a 160 year old, two storey, limestone. Running more ducts to the second floor is not an option (there are currently only two) but piping will be much easier. Boiler will be in the basement.



I've had a heat loss done by a local engineering group, the results should be here tomorrow. My guess is ~120,000 BTU from the Slant-Fin software. I'm going to get used cast iron radiators (which will look correct given the age of the house) with the EDR matched to the heat loss in each room.



This is what I'm hoping to accomplish myself: placing rads and running the lines. What material would you suggest for this? Pex (oxygen barrier) will be easiest from the second floor, although I had wondered about copper tubing. Comments about heat loss from copper vs pex?



On the first floor I thought I could just use copper, but perhaps pex would be better/easier? I can sweat pretty well (at least I think).



As far as actually connecting the radiators, I'm confused as to what would be best. Home run which doesn't make much sense unless using pex. Or do a reverse return two pipe with an 1 1/4 main running around the basement?



Or should I have the installer do the connections? My hope was that by running the lines I could save a considerable amount and be closer to a boiler replacement project.



Thoughts? Thanks in advance!

Charlie from wmass

I as a contractor prefer

one singer one song. When it gets into home owner doing part and contractor doing another part if , or when something goes wrong fingers get pointed but nothing gets fixed. If home running to manifolds I would use Pex. You could do reverse return or a monoflow system with trvs (thermostatic radiator valves) or home run with trvs. Or you could use these http://www.hydronicalternatives.com/Steam-to-hot-water-conversion-valve.pdf

Brad Barbeau

Yes,

Thanks, I know what you're saying. My concern is partly that I want to be the one who is putting the holes in the building, so I'll likely place the rads, and physically run the tubing and the contractor can connect it. There probably can't be too much finger pointing since I won't have actually connected anything, just put it in place.



I'm thinking of the Weil Ultra Oil because we don't have gas here so it's propane or oil. Propane is fractionally more expensive than oil and they seem to move in a similar relationship. Will that be short sighted?



Brad

icesailor

Propane and Oil:

Think of this. Or what I tell potential customers.

LP is oil. The "P" in LP stands for Petroleum. It comes from the same product. Oil.

What you pay for is the heat energy in the fuel in BTU's. For the sake of understanding, lets call 1 BTU, a penny, $.01. Lets take two buckets and put the amount of BTU's/Pennies for each fuel. There are 91,000 BTU/Pennies in this bucket of LP. There are 139,000 to 141,000 BTU/Pennies in this bucket of #2 heating oil. Knowing the price of the fuels, which one do you want?

I haven't ever had anyone choose the LP yet. And I don't care. I make the same money with either.

Under the above numbers, a 95% gas boiler isn't cheaper to run than a 85% oil boiler.

Brad Barbeau

Excellent

That's exactly what I was thinking! Since they are both tied to the price of oil they will both follow that price!



And that's assuming, I guess, that you are condensing and actually getting 95% all the time, otherwise the numbers get even worse.

icesailor

Cost/Efficincies:

You're smart, I'm not.



If you pay $3.00 per gallon for LP at 95% efficiency, at 91,000 BTU per gallon.

And pay $300.00 per gallon for #2 heating oil at 85% efficiency at 139,000 BTU per gallon,

Which costs more? Less? What's the best deal?

I'm not too good at old math. New math is hopeless.

I don't understyand it in Washington and I don't understand it here.

Brad Barbeau

Which boiler?

So I've got my heatloss - 120,000. Rads will hopefully be ordered today now it's just time to select a boiler. I like the Weil-McLain Ultra Oil particularly because the UO-3 has two nozzle sizes which means we can start with the smaller size and go up if needed (two phase project here with about 50,000 BTU being added later this year or next). The contractor is a Viessmann dealer but is happy to look at others. Ones I'm wondering about:

WM Ultra Oil

WM WGO

Burnham MPO

The Burnham MPO controls look nice but so does the optional one on the Weil Ultra. On the other hand the Weil's can have any controls used with them. Perhaps it doesn't matter?



Will a three pass save a huge amount over a pin (WGO)? AFUE are less than one percent different.



Thanks for your help.