Input needed on heating upgrade / conversion

PAOldHome

We are in the process of buying a 1900 home that has been converted into a duplex over the years and we will be converting it back to a single family. Currently each side has a gas boiler feeding cast iron radiators. The radiators work fine although the boilers are ready for the junk yard. Both lack an auto fill system and one is rusted from leaks and other issues to the point I would be hard pressed to justify spending any more on it. We have renovated a number of older homes including installing a hot water system from the ground up so we know what is involved if we go a different route.

My question(s) are:

1) Would you leave the cast iron radiators versus replacing the entire system with either hot water baseboard or even a ducted hot air system (realizing that installing ducts without losing the character of the house is tricky.

2) Would connecting the two sides into a single larger gas boiler be an option (possibly zoning the two sides at the boiler)?

3) What factors would you consider in keeping the current system versus replacing it with an alternative system; i.e., cost, complexity of installation, comfort, operating cost, etc.

Thanks in advance

jesmed1

As a homeowner and someone who appreciates old houses, I would urge you to keep the cast iron radiators. We have cast iron radiators now in a 100-year-old hot water heating system, and they are unbeatable (IMHO) for providing comfortable, even heat. If it ain't broke, don't fix it....

Grallert

Can we assume this is a hot water system as apposed to a steam system? If that's the case I think the simpler the better. Keep the radiators and install a new boiler or two, depending on the use of the building.
If there is enough radiation installed this would be IMO a good time to consider a modulation condensing boiler of the appropriate size. These can be easily zoned at each radiator or at each zone.

hot_rod

Adding TRVs on the radiators would give the tenants individual control. I don’t see a single zone being a good option in a duplex, which side gets the thermostat?

are the radiators in good shape, no leaks or corrosion on connections or fittings?

Plus they are already installed😉

leonz

Speaking as a homeowner;

If your future home is a heated with 2 steam boilers it would be simpler to replace them with one steam boiler and connect the loads together recreating a single heating load with one header pipe in the basement and adding the correct number of main vents in the new steam header pipe in the basement feeding both sides of the home.

In this home you have a huge amount of thermal mass with the cast iron radiators to take advantage of where a single new boiler with a double drop header would the radiators and piping heat faster and stay hotter longer.

Replacing it with hot water baseboard or ducted scorched would have increased cost and complexity when you already have the steam radiators and riser pipes in place in the correct locations and you would have to do a great deal more work when 99% of the work would be in the basement.

Hot_water_fan

Is this a part of PA where you anticipate you might want AC in the time when you live there?

Steamhead

@PAOldHome , keep the radiators. Don't let anyone talk you out of removing them, even for A/C.

Is this a steam or hot-water system?

Where in PA are you located?

PAOldHome

hot_rod said:

Adding TRVs on the radiators would give the tenants individual control. I don’t see a single zone being a good option in a duplex, which side gets the thermostat?

are the radiators in good shape, no leaks or corrosion on connections or fittings?

Plus they are already installed😉

We are converting the duplex back to a single family (will be our home). Overall the radiators are in good shape although there was one that has a leak on a fitting in the basement leaking onto the electrical panel (we contacted the seller / landlord to let him know of the safety issue. The boilers in place now are in less than optimal condition so replacing them would be a must do even if we keep the radiators.

PAOldHome

Hot_water_fan said:

Is this a part of PA where you anticipate you might want AC in the time when you live there?

It is in the Wilkes-Barre area . . . we get a few weeks of humid heat but not sure it justifies adding central A/C when a window unit or two would get you through those dog days.

PAOldHome

Grallert said:

Can we assume this is a hot water system as apposed to a steam system? If that's the case I think the simpler the better. Keep the radiators and install a new boiler or two, depending on the use of the building.
If there is enough radiation installed this would be IMO a good time to consider a modulation condensing boiler of the appropriate size. These can be easily zoned at each radiator or at each zone.

Appreciate the suggestion . . . . will have to look into the zoning suggestion you mentioned. As far as use, we would be taking the duplex and converting it back to a single family home (love the character of the older homes)

Steamhead

PAOldHome said:

Grallert said:

Can we assume this is a hot water system as apposed to a steam system? If that's the case I think the simpler the better. Keep the radiators and install a new boiler or two, depending on the use of the building.
If there is enough radiation installed this would be IMO a good time to consider a modulation condensing boiler of the appropriate size. These can be easily zoned at each radiator or at each zone.

Appreciate the suggestion . . . . will have to look into the zoning suggestion you mentioned. As far as use, we would be taking the duplex and converting it back to a single family home (love the character of the older homes)

@PAOldHome , if you're not sure whether this is a hot-water or steam system, post some pics of the boilers and a few radiators. We can tell you what it is.

KC_Jones

PAOldHome said:

We are in the process of buying a 1900 home that has been converted into a duplex over the years and we will be converting it back to a single family. Currently each side has a gas boiler feeding cast iron radiators. The radiators work fine although the boilers are ready for the junk yard. Both lack an auto fill system and one is rusted from leaks and other issues to the point I would be hard pressed to justify spending any more on it. We have renovated a number of older homes including installing a hot water system from the ground up so we know what is involved if we go a different route.

My question(s) are:

1) Would you leave the cast iron radiators versus replacing the entire system with either hot water baseboard or even a ducted hot air system (realizing that installing ducts without losing the character of the house is tricky.

2) Would connecting the two sides into a single larger gas boiler be an option (possibly zoning the two sides at the boiler)?

3) What factors would you consider in keeping the current system versus replacing it with an alternative system; i.e., cost, complexity of installation, comfort, operating cost, etc.

Thanks in advance

For me removing the cast iron wouldn't even be on the list. You will be very hard pressed to duplicate the comfort potential of them with any other system.

Exercise extreme caution on the bolded part. There is a very real possibility the entire house only needs 1 of the current boilers. Oversizing equipment is commonplace so it's very likely they are both oversized and you may need much less boiler than you think.

I've never fully understood the concept of putting in a 100% new system as keeping what you have, even in part, should always be the cheaper route to take, but I also DIY so it may be different when paying. Of course part of that difference can be influenced by what a contractor wants to do, and prices what he doesn't want to do accordingly, if you get my meaning. Your Mileage My Vary.

Operating cost, in large part, is going to be based on the house itself. The house has heatloss, and unless you purposely install a system wrong, the fuel cost to operate is going to be largely identical with exception of heat pumps, which are more efficient.

hot_rod

Do you like the look and placement of the radiators? For some people just getting that space back is enough of an incentive to remove them.
They do produce some of the most comfortable heat, is comfort is on the checklist.

Hot_water_fan

I think the decision to add central air can be independent of the remove radiators decision. It's your money.

PAOldHome

hot_rod said:

Do you like the look and placement of the radiators? For some people just getting that space back is enough of an incentive to remove them.
They do produce some of the most comfortable heat, is comfort is on the checklist.

Since it is a 100+ year old house and we wanted to restore it to what it was (have done several 1800 homes over the years), they do add to the character. They have a pattern - they are not just plain jane radiators. My wife's concern was the grandkids . . . might need to look at covers for those in area the kids would be running around in

With 3,200 ft2, not sure getting space back is high on the list but comfort is.

pecmsg

For now keep the radiators. 

Down the road A/C or heat pump can be added 

KC_Jones

PAOldHome said:

hot_rod said:

Do you like the look and placement of the radiators? For some people just getting that space back is enough of an incentive to remove them.
They do produce some of the most comfortable heat, is comfort is on the checklist.

Since it is a 100+ year old house and we wanted to restore it to what it was (have done several 1800 homes over the years), they do add to the character. They have a pattern - they are not just plain jane radiators. My wife's concern was the grandkids . . . might need to look at covers for those in area the kids would be running around in

With 3,200 ft2, not sure getting space back is high on the list but comfort is.

What's the concern?

CLamb

If you want an authentic 1900 heating system get an anthracite fired boiler. In the Wilkes-Barre area anthracite should be easy to find.

delcrossv

Keep the radiators, add SpacePak if you want AC. Removing a better system (steam or HW) to put in a worse one (scorched air) makes zero sense.

hot_rod

PAOldHome said:

Do you like the look and placement of the radiators? For some people just getting that space back is enough of an incentive to remove them. They do produce some of the most comfortable heat, is comfort is on the checklist.

Since it is a 100+ year old house and we wanted to restore it to what it was (have done several 1800 homes over the years), they do add to the character. They have a pattern - they are not just plain jane radiators. My wife's concern was the grandkids . . . might need to look at covers for those in area the kids would be running around in With 3,200 ft2, not sure getting space back is high on the list but comfort is.

A downside for remodel projects is painting the wall behind them or refinishing the floor below .

Unless you remove them to sandblast and powder coat👍🏻

bburd

Your current system has two heating zones. Assuming this is hot water, not steam, it should be a simple matter to replace the two boilers with one boiler that has two circulators or two zone valves, and keep those two zones as they are. This will cost less than installing two new boilers and keep you just as comfortable.

The new boiler should be sized according to the current heat loss of the house, and will probably be quite a bit smaller than the capacity of the existing boilers combined. As noted above, oversized equipment is very common.

You need to find a contractor willing to do a heat loss calculation. Too many don't. Try the "find a contractor" tool on this site.

PAOldHome

KC_Jones said:

PAOldHome said:

hot_rod said:

Do you like the look and placement of the radiators? For some people just getting that space back is enough of an incentive to remove them.
They do produce some of the most comfortable heat, is comfort is on the checklist.

Since it is a 100+ year old house and we wanted to restore it to what it was (have done several 1800 homes over the years), they do add to the character. They have a pattern - they are not just plain jane radiators. My wife's concern was the grandkids . . . might need to look at covers for those in area the kids would be running around in

With 3,200 ft2, not sure getting space back is high on the list but comfort is.

What's the concern?

The temperature of the radiators . . . . one of our rental properties has cast iron radiators and they are almost too hot to touch at times. We could use covers for units where the grand kids are going to be

jesmed1

PAOldHome said:

KC_Jones said:

PAOldHome said:

hot_rod said:

Do you like the look and placement of the radiators? For some people just getting that space back is enough of an incentive to remove them.
They do produce some of the most comfortable heat, is comfort is on the checklist.

Since it is a 100+ year old house and we wanted to restore it to what it was (have done several 1800 homes over the years), they do add to the character. They have a pattern - they are not just plain jane radiators. My wife's concern was the grandkids . . . might need to look at covers for those in area the kids would be running around in

With 3,200 ft2, not sure getting space back is high on the list but comfort is.

What's the concern?

The temperature of the radiators . . . . one of our rental properties has cast iron radiators and they are almost too hot to touch at times. We could use covers for units where the grand kids are going to be

Old houses with original cast iron radiators typically have so much radiator area that the house can usually be heated with low-temperature water. Our 100-year old 4-unit condo building in the Boston area has original cast iron radiators that heat the house with water temperatures averaging 100-110 degrees, and the radiator surface temps never exceed 120.

So if radiator temperature is your concern, get a proper heat loss calculation done for the house and get a boiler properly sized for the heat loss. If you do that, you won't end up with a boiler 3X oversized that overheats your radiators unnecessarily. A smaller boiler producing lower water temperatures will be more fuel efficient and more comfortable.

Ron Beck is a former US Boiler tech expert who wrote the following article. See paragraph 4, "Cast iron radiation" where he explains this.

https://www.usboiler.net/outdoor-reset-doesnt-work.html

KC_Jones

PAOldHome said:

KC_Jones said:

PAOldHome said:

hot_rod said:

Do you like the look and placement of the radiators? For some people just getting that space back is enough of an incentive to remove them.
They do produce some of the most comfortable heat, is comfort is on the checklist.

Since it is a 100+ year old house and we wanted to restore it to what it was (have done several 1800 homes over the years), they do add to the character. They have a pattern - they are not just plain jane radiators. My wife's concern was the grandkids . . . might need to look at covers for those in area the kids would be running around in

With 3,200 ft2, not sure getting space back is high on the list but comfort is.

What's the concern?

The temperature of the radiators . . . . one of our rental properties has cast iron radiators and they are almost too hot to touch at times. We could use covers for units where the grand kids are going to be

I have steam, the radiators are regularly over 200 degrees. Unless a child has a nervous system problem, there isn't an issue. These temps are such that the amount of time required to actually burn, is well beyond the automatic nervous systems reaction time to heat. In other words if a human gets burned, they did it to themselves on purpose.

These have been in houses for 150 years, if burning was an issue, they would have all been ripped out a long time ago, possibly even outlawed.

Also, I highlighted the part that kind of answers your own question. They are too hot to touch, that part of our nervous system is a protective system, we are born with it, so children will be no different than an adult, it's too hot for them to touch, or keep their hand on long enough to do damage.

If it makes you feel better cover them, but for me it's a complete waste of time.