Junk needs assistance HVAC technicians

PineRidge

Back From the Dead
The Junkster has gone and intalled a new LP unit heater in his garage. Yep, took him 4 weeks to do it but the 30 minute job is finally completed. Problem is the damn thing won't work and he keeps calling me at 3 in the morning for help. Are there any heating techs here that can help the poor ol' fart out? :yum:

There Junk that should get you some results........... all you gotta do is ask
 

Junkman

Extra Super Moderator
The old fart is sleeping on the couch and doesn't know the differance between 3 AM and 3 PM!!!!!! :whistle:

The unit lights and there is flame for 5 seconds and then it shuts off. The manufacturer doesn't have a clue as to what is wrong either, so they are sending me all new electrical parts to start replacing them. I guess that in the end, I will have spares for the future... Junk.....
 

Dargo

Like a bad penny...
GOLD Site Supporter
Ah, it sounds like your safety thermocoupler is shutting off your gas supply. I need to replace one on a ventless fireplace in my poolhouse. It keeps thinking that the flame has gone out and shuts off the gas supply at the most inopportune times. At least you can get warm for short periods of time. :D
 

OhioTC18

Member
GOLD Site Supporter
Junkman said:
The old fart is sleeping on the couch and doesn't know the differance between 3 AM and 3 PM!!!!!! :whistle:

The unit lights and there is flame for 5 seconds and then it shuts off. The manufacturer doesn't have a clue as to what is wrong either, so they are sending me all new electrical parts to start replacing them. I guess that in the end, I will have spares for the future... Junk.....

Junk, check to see if it has a flame detector. If it's not postioned in the flame correctly or if its dirty, you'll keep getting a no flame signal and it'll shut down. Every fall I have to take steel wool or emery cloth to mine and clean it up. If I don't the ignitor will cycle off and on and the detector won't allow the flame to stay lit.
 

OkeeDon

Charter Member
I think both Dargo and OhioTC18 are referring to the same thing, the thermocoupler, the pencil-like thingie sticking into a pilot flame. They are very sensitive to contamination; the oil off your fingers is enough to foul them up. Clean it with alcohol and see if that helps.
 

TOMLESCOEQUIP

Just Plinkin Away the $$
Hey Junkie- my house furnace was doing the same thing. The wall thermostat got bumped :pat: & the cover knocked off during a family get together over the holidays 2 Christmasses ago. It turned out that a setting in the thermostat that involves cycle times & temp. differential got slid over out of wack & that was causing the problem. I think Pineridge helped me on it. I had posted about it on TBN. Found it here's the link Found it ! You might want to try the t-stat before you start replacing parts..........it worked for me...........
 

Junkman

Extra Super Moderator
The unit doesn't have a thermocouple, but rather a heat sensor that looks very much like the porcelain igniter. The only outward difference is that it has two probes at the end. There are two other sensors on the unit that detect overheat situations if the flame should overspill the burners. I will check the thermostat settings to make sure that they are correct. The manual calls for a "4" setting which I set it for, but with my poor eyesight, I might not have set it properly. Easy item to check..... Thanks for the suggestion. Damn Pineridge didn't suggest that to me, but had me doing a lot of other things. I think that his thought process left when he shaved his head... :eek:
 

thcri

New member
Junk,

Make sure the sensor does not have a crack on the procelain. During shipment them sensors sometimes due to people dropping etc they prematurely break.

Another thing is make sure you have your gas pressure set right.

And last but maybe the first thing you could try is these new ignition systems are polarity sensitive. Make sure you have your hot on hot, neutral on nuetral and ground on ground. We put in about 400 Carrier furnaces every year and when we get electricians temporarily wiring them your symptons are the same. Run for 5 seconds then shut down. We just reverse the wires and they take off and run fine.

Also check the heat anticipator on your thermostat. It could be set wrong.


So get off the couch and try them.


murph
 
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dzalphakilo

Banned
First things first. Model number and serial number.

What is it doing when heat calls, or what is it not doing?

I assume (we know what that word means) that its electronic ingition.

Also assuming that it's wired to a t-stat, propane gas per this post, did you have to change anything for LP or is that the way the units came? Being in Ct., I have to assume that a high altitude kit is not nessasary (sp?).

From a while ago (post here) that it's the Mr. Heater line.

Have you called their technical support and mentioned your issues (and have they given you a response)?

Get me the model and serial and how you have it wired, plus the inlet pressure, along with how you have it vented in detail, and I should have a soulution for you.

Forgot, per mentioned here, heat anticipator (sp?) settiing on the t-stat. Had one job with 20 units in a commerical building and that was the issue.
 

Junkman

Extra Super Moderator
The said on Friday that the parts will be shipped on Monday by UPS. I figure that it will take about 3 days from Ohio to get to CT. I had already known about the reversed polarity of the electric and had check on that by reversing the lines. Made no difference. While they were trouble shooting the unit, they asked about the distance of gas line and the size. I had used approximately 21' of 1/2" black iron and 9' of 1/2" OD copper. They said that combination was good for about 125' and discounted that as the problem. My guess is that the circuit board is going to be proven to be the problem. I will let everyone know as soon as it is working.
 

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Boustany

New member
Junkman said:
The old fart is sleeping on the couch and doesn't know the differance between 3 AM and 3 PM!!!!!! :whistle:

The unit lights and there is flame for 5 seconds and then it shuts off. The manufacturer doesn't have a clue as to what is wrong either, so they are sending me all new electrical parts to start replacing them. I guess that in the end, I will have spares for the future... Junk.....

IF it were a high efficiency unit and IF it were cycling longer I would suggest you verify the water (out) pipe is not blocked.

Hey - waddayah expect - even the manufacturer doesn't seem to know ...
 

PineRidge

Back From the Dead
I assume that you've now cleaned the flame sensor and checked for cracks in the porcelain so we'll rule that out.

And by this time you have most likely checked the heat anticipator setting within the stat so we'll rule that out.

My guees is that it isn't the spill switch, most of them are manual reset or fusible links (once fusible links blow they need to be replaced) so we'll rule that out.

Don't think your piping is undersized but you can't really check whats happening at the valve sisnce you don't have a manometer.

I'm banking my money on a problem with your ignition board. A few years back we had major problems with Carrier/Bryant PC boards that had a cold solder joint on one or more of the component parts requiring feild replacement of the complete board. Guess the manufacturer figured we didn't know how to use a soldering iron out in the field.

Junk, hope you get it running before June or July. Send me a plane ticket and I'll come out and fix it for you for free.

Free= plane fare, good food, alcoholic beverages, & a road trip for you and me to go to Vegas...........
 

Junkman

Extra Super Moderator
The new circuit board arrived today by Next Day Air...... that is the good news..... the bad news is that one corner of the board is broken off. The good news is that it doesn't effect the printed circuit, so I installed it. The furnace fired right up and is working now. I believe that I know why the old board failed. It was over tightened to the case, and the screw holes were stripped out. They used 3 machine screws to hold it to the case and one sheet metal screw. One of the machine screws had its Phillips head stripped out also. Had to use a wrench to get that one off. Called the manufacturer and requested a replacement circuit board.....
 

PineRidge

Back From the Dead
Glad you got it up and running Junk. I figured it was the PC board but you never know. Please just send the $75.00 technical assesment fee to me when you can. :thumb:
 
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