My Mr Heater Bigg Maxx Install

[tarbellb]

what psi/bar rated gauge would i want for this exact same install?

100# tank
mr.heater maxx 45k btu
1/2" black pipe

i cant tell from the pictures?

 

[Chetter]

Thanks for the help.

I purchased and installed my wiring and boxes. I'm installing switch with an indicator as well. I looked at the twist lock plugs at hd today but opted to go with a regular plug as I had a few extras at home.

I have a electrican friend coming to
Make the connections, I could
Do it but would rather have a professional.

Still waiting for heater will add my pics when it
Comes.

I have the 45000 btu propane unit that has been in now for 3 years. I ran 12-2 armor cable wire and wired it direct to the heater and put in on it's own circuit. I used my old Honeywell round mechanical thermostat from my house when I went digital and it goes down to about 40-45*, I set it for 50* and leave it. I use two 40lb propane bottles, easier to handle a 40lb tank than a 100lb tank for me, with an RV auto switching regulator that switches from the empty tank to the full one and it allows me to pull the empty one out and take it to fill without shutting the furnace down. From the regulator I used 1/2" black pipe that goes through the wall with all the necessary shut off and drip leg. I have my tanks in a shelter that I built using some left over 4x4 pressure treated lumber and covered it with the plastic sheeting used for patios and such. I made a hinged half door that keeps the snow and critters out and my tanks stay dry and clean. It is not air tight but does keep 95% of the weather out. I love having a heated garage and it is nice to go out to go to work with no snow or ice to remove. I use an old shop vac to pick up water from snow melt. Sorry for long post.

 

[curiousB]

Hi gang, newb here.

I put the natural gas version of this in my garage 3 years ago as well. Best thing I ever did. Very happy with it, 3 car garage in IL. Can go from 0 to 65 in 1 hour (degrees that is). I previously had a vent free unit and I swear it made me feel sick. Also the water generated by a vent free was rusting all my tools!

So if anyone is debating vent free vs. vented. Go vented and get that exhaust and moisture out of the garage! I don’t believe the safety of these oxygen depletion vent free gas devices.

I also used an old Honeywell Thermostat salvaged when I went digital inside. Be sure to set the anticipator in these old thermostats. I measured the AC current in the thermostat loop with a DVM when the system was calling for heat. Then move the anticipator setting to that current reading. I just flip the switch from off to heat when I want heat in my garage. I only warm it up when I have work to do out there (or a football game to watch).

I vented vertical due to the many constraints of horizontal (have to use stainless steel vent in my area for horizontal) and all the other spacing/clearance restrictions made it unworkable for me. Just used B vent through the roof and shingle cap outside and spacing collar on inside. Just make sure at least 1” from all combustible surfaces.

After a week of usage I installed vibration hangers since I have a room above the garage. This made a major reduction in the vibration sounds upstairs.

I went black iron all the way into the unit with a shut off valve and service union in last foot of pipe just in case. I hardwired the unit to the nearest circuit (I didn't dedicate a branch circuit either). EMT conduit is code here so I ran that and used some water tight flex conduit the last 2 feet. I would recommend hardwiring and I think it is code in some areas (like a dish washer and waste disposal are).

First time fire up each fall is a bit of an odor as it burns off the dust and such collecting all spring and summer. Usually just last the first cycle.

I can’t say how much I enjoy having this heater. I also can’t say enough how much I recommend using vented heaters.

 

[tarbellb]

im planning on using a 300psi 1/4" ****** pressure gauge. is there any reason not to use this psi? i did some research and it looked like the pressure rises with the temperature, 110 degrees f = 225 psi? or something close to that.

also, where did you source that anti-vibration hanger? i cant seem to find a nice, cheapish, non heavy duty version?

 

[sarman47]

Happy Friday

Well I finally installed my Mr Heater 45,000 Big Maxx. Installed with brackets across the joists and threaded rod and double nut.

I ran CSST (yellow jacket) gas line from the basement to the attached garage. Coming threw the ceiling beside heater.

Ran BX cable for power to the garage from the main power panel to the ceiling above unit. Used a 15 amp breaker, so the unit has its own line. Installed a service switch by heater and hard wired power to heater.

Installed t-stat (Pro1) and ran 18/6 wire (tie wrapped to the main power cable) to heater unit, hooked up the G for the fan only option.

Had to go with the vertical venting, due to code issues (better safe then sorry). Will have pictures of venting soon.

I must Thank all you fine Men and Women on this site for the wealth of knowledge and sharing of information.

Have a great weekend

I will be having a warm one in the garage ...............

 

[z28dad]

Thats some great install pics above. I believe Im going to go ahead and install the vibration adapters. The other day, I was leaning against the wall and could feel the vibrations of the heater resonating through the structure.

I also need to measure the current of the t-stat, so that I can adjust the anticipator. The t-stat is not working like it should.

Curiousb, do you have a link for the source you used for the vibration adapters. Thanks, Russ

 

[curiousB]

Re: vibration control hangers

Its been too long that I don't recall where I bought them from. It was somewhere on the internet. Here's one mfg's pdf application guide. Just use the weight of the heater and add a bit for whatever piping and such will be hanging off of it. Then divide by four and find a hanger in the weight range. You don't want too small or the spring will full extend and you don't want it oversized or it will be too stiff and not isolate the vibration.

http://www.mason-industries.com/masonind/_doc/pdf/h610v8.pdf


I recall I paid about $15-17 each for them...

 

[68rustang]

McMaster has them:

http://www.mcmaster.com/#threaded-rod-vibration-dampers/=ffk42p

 

[Bill123]

Nice Job..

 

[pkoldman]

Just a great big Thank-You! I'm in the middle of installing my own Big Maxx 75,000 btu furnace, and this post has been a wealth of knowlege.

 

[TS057]

Quick question - do you know how many amps the blower motor draws? Did you put your heater on its own circuit?

 

[z28dad]

Quick question - do you know how many amps the blower motor draws? Did you put your heater on its own circuit?

If memory serves me right my unit the 75k ones draws around 5A. I actually put the heater and a receptacle that my 12k BTU window unit plugs into on the same circuit. I also used a switch with a pilot light to switch the receptacle that the heater plugs into. This way I can run my ac and know that the power is off to the heater. The heater plugs into a receptacle via a twist lock plug. We had so many severe thunderstorms this past year, I may just unplug the heater this spring.

Speaking of thunderstorms, I also purchased a Cutler Hammer surge protector that plugs into the panel via a 15A double pole breaker. Last year I lost one of my battery tender units because of a storm.

 

[z28dad]

I have been using the heater off and on this season. I still need to add the vibration isolators and I plan to do this soon.

I did notice that I have some discoloration on the first tubes at the bends of the heat exchanger. Can I get you guys to check your heaters to see if they are doing this. I may need to adjust the pressure. Thanks, Russ

 

[Mmfh]

I've been running mine for about a month or so now and so far no discoloration of the tubes. I have to say though, mine doesn't run very long before it shuts down.

Does yours run the fan after the gas shuts off to cool the heat ex-changer? After mine gets to temp the fan will run for another minute or so to cool everything down.

 

[z28dad]

The fan does keep running to cool the exchanger for several minutes. It could be normal. I looked at my flame and it just barely get to the first bend but does not go around it. Im planning on getting a manometer and make sure the output pressure is set to 10"wc.

 

[z28dad]

Guys, I have a question concerning the vibration hangers. I have ordered them, and they are on the way. Does it make a difference if I install them next to the strut or can I install them down next to the heater? Will it make a difference? The reason I ask is, a couple of my threaded rods are really close to the bottom chord of the truss and I really don't think I will have the clearance. I'm kinda thinking it wouldn't matter. I would also feel better about these being exposed and not covered up by sheet rock.

I have also ordered a manometer to double check my output pressure.

Thanks,

Russ

 

[z28dad]

Got some stuff today. I purchased a meter that measures up to 35"wc. Also the Vibration hangers came in. They are a little large. They are suppose to handle up to 50lbs. The heater weighs about 80lbs. I'm a little worried that they will be too large, but the spring compresses pretty easy and with the large rubber bushing I think they will work. I don't have a big vibration problem, just enough to bother me. I'm going to install these about half way between the ceiling and heater. I will keep you guys posted.

 

[dave67fd]

I would think they are rated at 50lbs "each". Using 4 would give you a 200lb max load rating.

Edit:
maybe read your post wrong. Your worried their too large physically?

 

[z28dad]

Dave, I was worried that I wouldn't have enough weight to compress the springs, but I think I will.

 

[rponfick]

One suggestion I would make is to always install a CO meter/alarm in the heated garage.

Our local vent code calls for stack to be 2 ft. taller than anything within 10'. My main roof is 12/12 pitch and I have a 3/12 area on the edge of my roof where my vertical vent is located. I have extended the stack a couple of times to prevent CO buildup when winds come from certain directions. I am within code, but I still set off the alarms on some days. My heater is an older Janitrol unit and is not power vent, and I wonder if changing to a power vent would help my situation.

So, a couple of CO alarms are cheap insurance in heated garages (and in houses to, for that matter).

Ralph.

 

[dave67fd]

One suggestion I would make is to always install a CO meter/alarm in the heated garage.

Our local vent code calls for stack to be 2 ft. taller than anything within 10'. My main roof is 12/12 pitch and I have a 3/12 area on the edge of my roof where my vertical vent is located. I have extended the stack a couple of times to prevent CO buildup when winds come from certain directions. I am within code, but I still set off the alarms on some days. My heater is an older Janitrol unit and is not power vent, and I wonder if changing to a power vent would help my situation.

So, a couple of CO alarms are cheap insurance in heated garages (and in houses to, for that matter).

Ralph.

This is a no-brainer in a "garage". Heat or no heat.

 

[z28dad]

I think I finally got this heater project wrapped up, just in time to turn on the AC unit.

Today I installed the Amber/booth BSRA 1-50 vibration hangers. I can't believe what a difference these things made. I only ran the heater for about 5 minutes but I could feel no vibration resonating through the walls.

I hope I installed them correctly. I just used washers and two nuts that I jammed locked together.

I finally got around to measuring the output pressure. I had originally adjusted the flame just before it entered the first bend of the heat exchanger. With the heater on it was only at 5 in.H2o. So I set it up to 10. The flame does go past the first bend in the heat exchanger, but the heater really puts out the heat now.

Let me know what you guys think. Thanks for all the help in this thread. I'm sure it will be very helpful to anybody installing this heater.

 

[Highbeam]

What worries me is that the springs allow the unit to move up and down. The flue connection is rigid. So is this going to pull apart your flue?

 

[z28dad]

It doesnt move that much. The case of the unit has a large hole cut for the flue so no worries.

 

[z28dad]

I double checked tonight with the unit running and you cant see the unit moving, or the springs. Whats neat is if you feel the rods on the heater side you can feel the vibrations of the unit. If you feel the top rods there is no vibration.

One other thing Ive noticed, ever since I turned the gas pressure back to 10, there is a slight red glow in the first bend of the heat exchanger. This is only visible if the room is in total darkness. This was the reason I thought maybe the pressure was too high, but now I have set it with a gauge. I also have discoloration in the first bends.

Can anybody else confirm this with their heater. This is a 75k btu, LP unit.

Thanks,

Russ

 

[curiousB]

I read somewhere a poormans way to check gas setting and BTU's is to turn on unit and (make sure all other gas appliances are turned off) then go to your gas meter and note the reading and then 15 minutes later (900 seconds later) take a new reading and compute the BTU used.

 

[rponfick]

I think the gas meters read in hundreds of cubic feet, which has nothing to do with BTU content of the gas. Most utilities dilute rich natural gas with air to arrive at some average BTU they put in their lines. Check with your local utility and they should be able to tell you the BTU's in their gas.

As a side note, some rich gas out of wells has so high a BTU that it will melt your pots on the stove. That is why it is diluted to a common standard. I worked the oil and gas field for 35 years, but now spend my time in the garage.

Ralph.

 

[rponfick]

I need to correct my previous post. As I was mowing the lawn today I looked at my gas meter. It has a 1/4 cu. ft. dial, a 1 cu. ft. dial, and then the first numbered one is 1000 cu ft.

I guess you could turn on your unit (with all other gas users off) and then go sit in front of your meter of a certain length of time, and measure cu. ft. used (using the 1000 dial would be too crude). Then, if you multiply the cu ft volume used by the BTU content of your gas, you could come up with an amount of BTU's being used by your unit. Your output in BTU's would depend on the efficiency of your unit.

Ralph.

 

[Skip707]

How do you install the isolation transformer? If you isolate the 24v from the R terminal on the heater and then connect the W terminal from thermostat to the W on heater the 24V from heater R terminal will not be the connection to the heater W terminal since its isolated. Thanks

Beware of the programable thermostat. If it is micro-processor based it "could" cause problems with the Big Max. They recommend using an isolation transformer between the therm and heater.

Also, you might consider mounting another switch right at the heater or to the ceiling in close proximity for local service/testing, it's also code in some locals.

The Permatex Red or copper Hight temp RTV will work well. Any auto parts store will carry it. You can also get the Dow Corning Silastic but i think it's harder/more expensive to get.

Installs looking good. Nice detail on the pics.[/QUOTE]

 

[Mark Mr.Oz]

Well I guess I am to the operational point of asking another question....Fired up the heater today (on propane as it has had the conversion)..I noted that the 3 burner jets flame out into the tubes but there is "wasted" flame in between the tubes? Is the water column or pressure to low? I also noted (in the dark) that only the center tube has a light red glow (at the first bend only). Am I not running the heater hot enough? I don't know the water column setting for sure as it was only leak tested by the installer. The unit seems to be keeping its own but not performing as well as I imagine it should be. Any input? What do you fellows see on your Big Maxx units? Also is the water column adjusted by the pressure screw under the plastic cap? Thanks in advance!!