Kickspace heater with Steam heat solution

jmiris

Hey Everyone,

So we are remodeling our kitchen and have a two pipe steam system, I live in an apartment building so I can't change that. We are very limited on space and would love to use a kickspace heater. A plumber I talked to said I should just hook it up to the hot water supply for my buildings potable water, but I worry I would be using a ton of potable water since I imagine it would have to go back down the drain, plus it will only reach about 120 degrees most of the time. My idea is what if I hook up the steam heat to a heat exchanger, and then on the other side of the heat exchanger put water in a closed loop with a circulation pump to feed the kickspace heater. Is this a crazy idea, should I just do what the plumber suggests or is there some other solution I am not thinking of to heat this space. I could even have the kick space heater and circulation pump kick on with a thermostat outlet and connect it to the steam pipe. Please any help would be super appreciated. Thank you.

Intplm.

Hooking up to the domestic hot water is not enough BTU's and, well, so many other reasons so don't do that.

There might be a way to hook up a heater using condensate from the steam. This is done commercially but I do not know if it is feasible residentially.
Hopefully others will be able to offer something.

Mustangman

What I have done before is connect supply and return piping into the steam boiler below the water line. Typically there is always a way to connect to that part of the boiler, below the water line, via plugs in the castings. You will also need an aquastat installed into the boiler set to 180. That keeps the water below the water line hot. You could use a single zone switching relay which will take the signal from the stat and engage the boiler ( to 180 set point on the aquastat ), it will turn on a circ. Thats the way I have done it in the past and it worked great. I will tell you, that you need to flush all the sediment off the bottom. Then skim the whole system. Start off clean so you don't go throwing dirt into your kickspace.

Glenn_Venco

The idea of using your domestic hot water as a heat source is patently absurd. Where did he propose the return side of the heater would be discharged to ? RUN AWAY from this guy. Yes, you would have a significantly higher water bill. Your hot water supply temperature would most likely be around 115F-120F. The heat output of a kickspace heater is substantially reduced at these lower temperatures. Depending on the flow rate through the heater, it could be by 35%-50% less, or more. Depending on the heater brand, they would typically have a thermostatic surface mounted sensor that would turn the blower on when the hot water flow through the heater approaches 140F or more. That means you would have to get a lower temperature aquastat.

You might consider pumping hot water out of your steam boiler, below the water line, with the circulator on the return side, pumping into the boiler. This will shield it from the excessive high temperatures. Use a S/S or bronze body circulator as they stand up to higher operating temperatures better and will last longer. Be sure to use a wye strainer on the hot supply coming out of the boiler to minimize the sediment/crud coming out of the boiler being circulated around into the heater and circulator. Also use an aquastat on the supply side, close to the boiler, set at approximately 170F, inserted into the kitchen zone demand circuit wiring so that if the kitchen calls for heat when the main thermostat is not calling, it would not cause the boiler to create steam when its not wanted/needed. One last thing - DON'T USE PEX for this piping. If the kitchen is located above the steam boiler, you will need addititonal check and ball valves. Search for piping a hydronic zone off a steam boiler. You should find the diagrams you need.

Jamie Hall

First, as the folks above have said -- don't use the domestic hot water. That idea is simply daft, not to mention an appalling waste of water.

Now. You say you are in an apartment building, so I'm going to make a guess -- you can't get at the boiler. So although the suggestion to take water from the boiler and circulate is an excellent suggestion, that's out.

Your best bet is your heat exchanger idea, although that's a bit complicated. Before you do that, is there any chance of putting a steam radiator somewhere in the remodelled kitchen? That would be a lot simpler and cheaper...

ChrisJ

When he said to use domestic hot water, is there any chance he meant with a recirculating pump?

I've been told it's common to use recirculating domestic hot water for towel warmers in bathrooms. Of course, such fixtures must be lead free and meet all requirements for potable water.

Also, there's a big difference between a towel warmer and attempting to heat a space with the water.

Sylvain

another discussion about kitchen remodel and steam:
https://forum.heatinghelp.com/discussion/comment/1794887

It is always useful to be able to dry towels in a kitchen.
A towel warmer used with steam would provide a lot of heat.

I hope the OP is still in the planing phase of the project.

EBEBRATT-Ed

Use an electric fan coil unit, baseboard or an electric kick space heater.

Anything else will have too much expence or will not work well

ChrisJ

ChrisJ said:

When he said to use domestic hot water, is there any chance he meant with a recirculating pump?

I've been told it's common to use recirculating domestic hot water for towel warmers in bathrooms. Of course, such fixtures must be lead free and meet all requirements for potable water.

Also, there's a big difference between a towel warmer and attempting to heat a space with the water.

@Mad Dog_2 What do you disagree with?

Sylvain

The op didn't explain how DHW was heated.

Mustangman

There are some hybred systems out there that use a gas water heater and an air handler to both heat the house and provide hot water. First thing is they jack up the water heater temp to 160 or so and put on a taco 5000 mixing valve set at 120 degrees for domestic. The whole house air handler is made by First Company.. It has a coil that is a little heavier than most as its under house pressure all the time. They have a 006 If you really want to use a water heater, thats the way to go. The return from the coil goes into the CW feed to the water heater with check valves. The down side.. a tank water heater is not very efficient .65 factor. Tankless is in the .95 range. The steam boiler is probably .80. More than one way to skin a cat. Some are better than others.

jmiris

Jamie Hall said:

First, as the folks above have said -- don't use the domestic hot water. That idea is simply daft, not to mention an appalling waste of water.

Now. You say you are in an apartment building, so I'm going to make a guess -- you can't get at the boiler. So although the suggestion to take water from the boiler and circulate is an excellent suggestion, that's out.

Your best bet is your heat exchanger idea, although that's a bit complicated. Before you do that, is there any chance of putting a steam radiator somewhere in the remodelled kitchen? That would be a lot simpler and cheaper...

Wow I did not expect so many comments so quickly, I really appreciate the help from everyone. I will clear it up with him tomorrow exactly how he thinks we should do this with hot water. Jamie Hall The only other thing that might fit is a baseboard heater but it wouldn't be very long and certainly wouldn't be enough Btu's to heat the space. I know my heat exchanger idea is a bit complicated but does anyone think it wouldn't work?

Mad Dog_2

Using Domestic water as a heat source...mad Dog 

ChrisJ

Mad Dog_2 said:

Using Domestic water as a heat source...mad Dog 

You've never seen anyone use it for towel warmers?

jmiris

So the plumber and I talked to clear things up, he says he would use the hot water and feed it back to the supply with a T fitting so it would not waste any water. He said for the space Im trying to heat with the blower on the kickspace heater it should work, but just incase I am going to test it out before we are done with planning to make sure it works. I'll report back when I have results hopefully next week.

ChrisJ

jmiris said:

So the plumber and I talked to clear things up, he says he would use the hot water and feed it back to the supply with a T fitting so it would not waste any water. He said for the space Im trying to heat with the blower on the kickspace heater it should work, but just incase I am going to test it out before we are done with planning to make sure it works. I'll report back when I have results hopefully next week.

Yeah it would work, and won't waste hot water.
But it'll be more expensive to run, depending on how you're producing your hot water. That's what others have told you.

Dedicated water heaters aren't known for being efficient. They're all about cheap and fast.


There's also concerns that the heater you have isn't intended to be used with potable water. Does it say it is?

jmiris

ChrisJ said:

jmiris said:

So the plumber and I talked to clear things up, he says he would use the hot water and feed it back to the supply with a T fitting so it would not waste any water. He said for the space Im trying to heat with the blower on the kickspace heater it should work, but just incase I am going to test it out before we are done with planning to make sure it works. I'll report back when I have results hopefully next week.

Yeah it would work, and won't waste hot water.
But it'll be more expensive to run, depending on how you're producing your hot water. That's what others have told you.

Dedicated water heaters aren't known for being efficient. They're all about cheap and fast.


There's also concerns that the heater you have isn't intended to be used with potable water. Does it say it is?

My building produces the hot water, and it's a large 50+ apartment building. You'll have to forgive my poor understanding of all things plumbing. I know my options aren't Ideal but when it comes to heating the space I somehow have to find an option that doesn't take up a ton of space or cost a ton to run. Electric heating options cost a ton to run where I am, in supply and delivery charges you could be looking at around 30 Cents a kWh total, so those are out. My building supplies Two Pipe Steam and DHW, so those are the most affordable options for me to use. My heat exchanger Idea, while complicated, is the idea that makes sense to me for getting the most heat out put out of a small space like the kickstand heater. But using DHW on the kickstand heater is certainly the easiest to do. Fortunately my building has a good envelope and even a little bit of heat from the Kickstand heater will make a big difference when it's really cold out. Hopefully it works.

Sylvain

So the DHW is common to the 50+ units.
I would not use it for heating and certainly not if it is going back to other families.
The heat exchanger makes sense if you can not install a steam radiator.

The heat exchanger, circulator and expansion tank are costly for just one small radiator.
Personnaly, I would change my kitchen layout to be able to have a steam radiator.

EBEBRATT-Ed

For a simple kicks pace heater buying circulators, a heat exchanger, expansion tank ETC ETC will be way to expensive for what you need. Plus the labor to install it.

Have the electrician run a circuit and use an electric kick space heater.

pecmsg

50+ Apartment building how can you do anything with the mechanicals? That would all have to be approved by the building staff.