Switch from steam to Hydronic/Hot water Coils

MickeysDaughter

Good evening, what are the pros and cons of switching from steam to hydronic furnace with hot water coils to be placed on existing air handlers? Essentially, using existing AC ductwork and air handlers to deliver heat, and abandoning steam system. Adding hydronic furnace. I feel like I will forever be repairing the 100+ year old steam system (i already need a new boiler which has brought this to the fore…so I either stick with steam or go in different direction altogether). Grateful for feedback. 

Steamhead

Keep the steam. No forced-air system will ever equal the comfort and efficiency of steam.

EBEBRATT-Ed

Depends on who is doing the work. The people recommending hot water with heating coils probably are not steam men.

So only you can decide. Get the right steam guy and fix what you have or convert to hot water. If you can't find the right person to fix the steam you won't be happy with it.

But a sloppy hot water job isn't much better

You need the right person to design a new system that will work without band aids.

Bottom line is that a big hunk of cast iron radiation heats better than anything else

pecmsg

You don't say where this home is located. I assume your also changing the A/C system at the same time so Id recommend a heat pump for the shoulder seasons. Id keep steam but you MUST find a steam contractor to do the work.

You said yourself that steam system has been there 100+ years, that speaks volumes of its longevity.

KC_Jones

MickeysDaughter said:

Good evening, what are the pros and cons of switching from steam to hydronic furnace with hot water coils to be placed on existing air handlers? Essentially, using existing AC ductwork and air handlers to deliver heat, and abandoning steam system. Adding hydronic furnace. I feel like I will forever be repairing the 100+ year old steam system (i already need a new boiler which has brought this to the fore…so I either stick with steam or go in different direction altogether). Grateful for feedback. 

You will feel like you are repairing it forever if you have a garbage contractor in your house. The person that was there in your last post that didn't recognize the basic issues is not the person you want to be talking to.

There isn't much love for conversions on this website.

For reference we see just as many hot water nightmares on this site as we do steam, so don't assume the contractor is magically going to know what they are doing when they start working with a hot water system. IMHO there are more technical details to get correct with hot water than there are steam. The person that looked at your system already, doesn't even understand water flows downhill...

Jamie Hall

Flawed assumption number one: "using existing AC ductwork and air handlers". Nope. Depending on how well they were designed and installed, they may work well enough for the AC, but unless they were intended to handle heating loads -- which are much greater, unless you are down south somewhere -- they won't do well with heat, and they won't distribute the warm air properly.

Not that it can't be done. I -- and most of us -- wouldn't recommend it, but if you do decide to scrap what's working and do this, as @pecmsg implied, don't do the hydronic bit. That is a waste of time and money. Redesign and rebuild the entire system and go with heat pumps.

clammy

A hydro air system will never provide you w the comfort of either a steam system or hot water system . Generally your electric and fuel consumption will increase and unless done correctly there usually noisier then the before mentioned ,personally I ve yet to see a hydro air system installed which I would consider great . . If your air handler is in your attic then measure will have to be taken to ensure that a freeze ups does not occur . I personally don’t really get invouled w them I see then in opposition to what I do ( which is sell comfort )and find them to be master minded mostly by gc looking to save there spending bucks and maximize there profits being none want freeze stats or check valves to stop thermal migration . When I do I make sure they are not in a attic and that every thing is done completely on the up and up . I’ve seen enough bad hydro air w gravity flow durning the cooling season and or basically all the time that I shy away . I will agree they do have there place but to do a whole home hydro air I feel is a waste of energy both fuel and electric from roi and operational costs and stand by . Just my opinion but there done all the time and the 2 birds one stone thing I guess is working . But I feel that true indoor comfort using hydro air and excepting the same level of comfort as hot water is a hard target to hit ,but with all the zone damper and motorized and barometric by passes one should after great expense get it right . Instead of hydro cut to the chase and have a hot air furnace installed usually cheaper then a hydro air which means you need a hot water boiler and a air handler and coil remember non will every provide the same level of indoor comfort as steam and hot water based system and w any air based system the thermostat will be set higher to feel the same level of human comfort as provide by system that do not move air just a basic reality moving air across human skin leaves a cooling effect not so much w convection based systems just some food for thought . Plus when the fan blower shuts off there no residual heat to be transmitted it s done ..Best of luck peace and good luck clammy