Help me shut down my Modine heater in the garage.

mudpie

I am new here and trying to learn new things, do more myself.
We bought a house in New Hampshire that has a Modine heater in the garage, holy cow are we burning oil heating the garage.
So, I found there are two pipes for water, one goes into the top of the unit, then one comes out the bottom, which I believe sends water back to the boil to be re-circulated because it is a closed system.
If we are going to shut this down, I believe I need to unhook the thermostat and drain the water from the system. There is a hose hookup to drain the water. Now, my biggest question is this: If I let water out through that hose hookup and drain it, will ALL the water in both pipes come out, thus making it safe for me to shut down and not worry about the water in the pipes freezing?? There is a shut off valve at the boiler for these two pipes. So I can stop more water from going to the unit, that is easy to shut down. But I am worried about water that was sent from the unit back towards the boiler still being in the pipe. Hope I am making sense. thanks. Mike

billtwocase

Does your system have antifreeze? If so, shut down would be a snap. You need to isolate, and blow all the water out, and disconnect the thermostat. If there are no isolation valves, and drains, I would hire someone to set it up for future fill and drain

mudpie

I checked the water for anti freeze by draining a little, seems like none in there. I have read articles that say do not put anti freeze in there. Anyways, still trying to figure out the draining of the water.

SWEI

How is the heater controlled? Is there a garage thermostat and a zone valve? Any idea what the previous owners did to manage this?

Can you post a photo of the heater piping and any valves nearby, as well as one showing the takeoff from the rest of the heating system? There are a couple of ways to make this work depending on the age and type of system.

mudpie

the unit itself on the wall.

mudpie

these are the pipes at the boiler in the basement that then lead out and over to the garage.

billtwocase

What are those 1/2" pipes behind it? Is there plumbing above the garage? If so, you may want to rethink shutting down the heat in the garage

mudpie

those pipes behind it belong to the Modine unit. That is them coming up the wall and over to the unit.

SWEI

Do you want to heat the garage intermittently, or just remove the unit heater from the system altogether?

mudpie

remove it. Well, shut it down and leave it there in case we want to use it again in the future. But shut it off and drain it so nothing freezes.

billtwocase

Sorry mud, eyes are rather tired today. They looked smaller than 3/4 from here.

wogpa67

If they would've put drains above the basement valves you be golden. Pull the hy vent open the boiler drain in the garage and gravity will work it's magic.

mudpie

Wogpa67, still not sure what you mean? what is the 'hy' vent?

wogpa67

The vent off the top of the unit heater.

mudpie

????

mudpie

talk to me like I am an idiot, tell me exactly what to do....because I am an idiot...ha ha..

Canucker

You're not an idiot, you're inexperienced. If you look at your first pic, to the left of the red handled valve, at the elbow above the heater, you have a vent. If you remove that when your drains are open, the zone will empty

wogpa67

Yes the unit heater will empty. But they didn't put drain valves down by the boiler.

wogpa67

The exposed piping in the garage will still have water in them.

mudpie

oh, that round thing that has a touch of paint on the top of it ? So take that out, then open the drain by turning the black handle under the unit.

mudpie

I still need to shut off the water valve down at the boiler correct? so I am not sending more water up to the unit.?

mudpie

Wogpa67, that is what I am trying to figure out, how to get that water out of those pipes leading to the unit. So if I pull that valve out and then open the black handle it will only empty the unit itself and not all the water in the pipes leading into the unit and all the water heading back down to the boiler?

SWEI

The takeoff photo you posted looks like two supplies or two returns. You would need to add a drain above the supply and the return which serve the garage heater.

mudpie

okay, so it looks like I cannot get that water out of the pipes myself

wogpa67

^
What he said. That's only one side feeding the unit heater.

mudpie

okay, I am learning some stuff here, but disappointed to know that I cannot do this w/out the plumber. So, here is another question, what are these above my boiler?

SWEI

mudpie said:

what are these above my boiler?

Zone circulators -- one per thermostat/zone. One almost certainly feeds the garage, in which case the valves you posted photos of above would be on the returns. The good news is you have isolation valves for everything. The bad news is no drains on any of them that I can see. You'll need to add at least one drain on the garage return pipe in order to get the water out of the zone (using an air compressor.)

mudpie

Thanks for all the help everybody, I have given up now thinking it is something that I can do myself. But at least learning how some of this stuff works. Thanks again,

Mike

Bob Bona_4

With a few controls, and relative confidence about not losing power, there is a way to protectthe heater from freezing with out adding nasty glycol or half way efforts to drain the zone. It involves circulating water thru the loop if the garage ambient drops below a preset temp..typically 35 degrees.

icesailor

Nice original install. Too bad they didn't put proper drains in the cellar so as to be able to properly drain the thing.

Those IFC's are a wonderful thing. How do you get the IFC's open when you want to drain the garage zone or the system. "Split" the difference?

SWEI

Like I said, there are a few ways to deal with it. Bob suggested one option.

The single drain method would involve removing the zone circ and blowing air into the flange. Not easy, but relatively cheap. Adding a second drain would obviously be better.

icesailor

SWEI said:

Like I said, there are a few ways to deal with it. Bob suggested one option.

The single drain method would involve removing the zone circ and blowing air into the flange. Not easy, but relatively cheap. Adding a second drain would obviously be better.

There's never enough time to do it right, but always time for someone else to do it over. The "Obviously Better" comes under the slogan "If you do it right the first time, no one has to do it over". Put in the second drain.

mudpie

I have a call into the plumbing company who originally installed it for the previous owner of the house. Hopefully they will come out this week and give me a fair price on shutting it down.

mudpie

Bob's recommendation is written down on a piece of paper and I will ask the plumber about that. It gets mighty cold around here, so if we go that route the system will be sending water a lot. Is it worth it or better to shut it down completely and never think about the thing again....we'll see.

Bob Bona_4

Wired right, the circ pump will move water around but there will be no oil burner interface, unless there is an actual call for modine heat. The relays would be seperate. A 007 circ draws about 60-80 watts. Not too bad.

Bob Bona_4

Couldn't edit for some reason. The major components needed would be a Honeywell fan center, a thermostat with at least R, G, and Y (C would be nice) connections and the appropriate conductors, a tekmar 150 setpoint control, and a Taco HAFC201 relay. The ability to get a 6 conductor or more 18 gauge wire from the modine to the boiler area. And the know how to tie it all in

Bob Bona_4

Made a mistake, and edit button still inop. Should have read "thermostat with R, W, G connections". C would be nice to rob 24 volt from the Taco HAFC201 so the stat doesn't run solely on battery power.