Sometimes it is a good idea to listen to your helper.

[DavyB]

Last week I went on a call to one of our projects from last year. A school multi-purpose room with 4 units. Two 25t and two 7.5t rtus. One of the 25t Yorks had signs of overheating such as warped ignition controls and brittle wires. I found 1st stage gas valve's pilot valve seized open.

I was sure that this was the cause for the signs of excessive heat.

Replaced the modules, valve and wiring and fired it up. (Told my helper to stand back in case of a problem). Boom! The furnace sounds like someone through an m80 into it.

We pull the burner assembly and everything looks decent except for some discolored areas near the burner tubes and electrode.

At this point I know that the gas valve is not the culprit. I begin spinning my wheels and believe the pilot crossover tubes may be blocked at certain spots. I'm beginning to get stumped so I give tech support a ring.

I tell him what's going on and he recommends cleaning or replacing the pilot crossover tubes. I ask him if gas pressure could be an issue and he says no. He said that many units run under rated pressure just fine. I also asked if too much pressure could cause it and he said no. The manifold reduces pressure to 3.5". I agreed, as no other units here shared these symptoms. So I order the crossover tubes that seem to be in good condition.

My helper says," We should check gas pressure". I say go ahead but don't you think that the other units would have similar problems?" He agrees and doesn't check it.

Next trip out, replace crossover tubes, check heat exchanger, check gas pressure. 25"WC supply. I knew it as I pulled the allen nut out of the valve and it blasted and equalized. purged the gas and put my manometer back on and watched it climb form 13 to 25 after 10 minutes.

It doesn't happen everyday, but that day, I should have listened to my helper.

[dandyme]

when you think it's trivial it'll bite you in the azz

[amickracing]

There's been a few people who know nothing about HVAC that have helped me solve some pretty tricky problems.

It's not hard to over think things and sometimes that know nothing perspective is the best one.

[DavyB]

There's been a few people who know nothing about HVAC that have helped me solve some pretty tricky problems.

It's not hard to over think things and sometimes that know nothing perspective is the best one.

Agreed. Got to start with the basics.

[Control Man]

Yes you never know when the question they ask is the solution to your problem.

Few weeks ago we had a wicked snow storm , went out to the garage to start the snowblower , of course it always starts but not this time ,on the 42nd pull I broke the pull cord.

My 7 year old grandson was helping me take off the recoil starter , asked 3 times :( what this BLACK BUTTON was for , 3rd time I finally told him , thats for the ELECTRIC START :) .


Had the darn blower for years and never used the electric start. got an extension cord plugged it in hit the button and AWAY it went. His comment was " Good thing I asked , right Grandpa "

[delo]

Yes you never know when the question they ask is the solution to your problem.

Few weeks ago we had a wicked snow storm , went out to the garage to start the snowblower , of course it always starts but not this time ,on the 42nd pull I broke the pull cord.

My 7 year old grandson was helping me take off the recoil starter , asked 3 times :( what this BLACK BUTTON was for , 3rd time I finally told him , thats for the ELECTRIC START :) .


Had the darn blower for years and never used the electric start. got an extension cord plugged it in hit the button and AWAY it went. His comment was " Good thing I asked , right Grandpa "

All you have to do is watch the TV show "are you smarter then a 5th grader to gain perspective .

[DavyB]

That same day I called the super on that job and told him about the gas situation and tried to explain that the regulator was bleeding by. I wasn't sure who he should contact to fix the issue, the plumber or the gas co.. He acted as if I was insulting someone as he said the plumber has nothing to do with it! blah,blah. I told him that I wasn't blaming anyone for the problem, I was trying to find the tech that is responsible for replacing the defective component. He said," Oh, you're not blaming anyone?" I told him that I'm sure that the pressure was adjusted but the regulator was made by a human and that things made by humans fail, get the regulator replaced.

He called me yesterday to tell me that the gas company said that the plumber was supposed to adjust it and he never did. There it is.

*Note to self* Check gas pressure on every start-up. Cutting corners only makes things tougher. You live and you learn.

[Drunkgoat]

i usually make a start-up sheet for all new start ups. and i measure incoming gas pressure, lock up pressure,manifold gas pressure. blower amps and i usually stick my analyzer at the exhaust and see how its burning.