MPF's Munchkin numbers

WaterHeaterGuy

Rules for the offset screw:

1)It should never be adjusted in any mode other than low fire.
2)It should only be adjusted when working with a digital manometer sensitive enough to read -.xx" W.C. (hundreths not tenths) and a calibrated combustion analyser.

When working correctly, the offset should be reading a -.02" W.C. With this reading, the inherant safeties of the valve can operate correctly. If you were to power the gas valve, without a blower pulling on it, the valve will not open. If someone brings the offset to a positive number, it is then possible for gas to pass though the valve.

When you give additional gas on low fire (to help smooth out a rough ignition for example) you could potentially bring it too rich --- or make a positive pressure on the offset --- and this would effectively remove the inherant safety of the design.

This is the reason that they do not publish information on it. They don't want people potentially messing up that relationship. The offset is set from the factory, and it should remain in that position for the unit to operate the way they say it will. It is a rare occourance for the offset to change during shipping, if it happens then an adjustment should be made.

Hope this helps.

Unknown

Well,,,

I got the new Fyrite Insight loaner yesterday. I say loaner because the real one is apparently still at the factory waiting for a plastic piece. **** (not quite sure of his last name) who I believe is the NE Bacharach rep was kind enough to UPS me his demo unit so I could put this Munchkin thing to rest. Sort of.
Readings done with cover on. Kind of a pain but figured it was the best way. I'd hate to find out the hard way that the numbers changed on me if I did them open and then put the cover on. So here's the info:

Low fire-
O2-4.6
CO-4 ppm
Eff-97.6
CO2-9.2
T Stak-97*
T air-65.9*
EA-24.9
CO(O)-5 ppm

All within range, then:

Hi Fire-
O2-3.9
CO-58ppm
Eff-93.5
CO2-9.6
T Stak-118*
T Air-65.7*
EA-20.5
CO(O)-70ppm

So OK, on hi fire my CO is low and my CO2 is high by 0.1 Increasing the gas flow with the throttle increases CO but also drives CO2 higher as well, so this is where I left it. Can anyone give me some insight on this info. I imagine I'll call the factory on Monday but I figured some of the guys here with experience on them might be able to shed some light on this discrepancy. Thanks!

And yes, I changed the pump to horizontal shaft configuration and while I was at it gave the unit a tad more pitch to the rear just for good luck.

So far the new Insight seems pretty sweet!

I'd like to note that in a time honored workmanlike fashion the original notes were in fact taken on an empty Wendy's bag found on the passenger side floor of the van. In the process I've discovered Wendy's bags have a lot of good blank notating space on the reverse. The notes were, of course, later copied into the manual. I have the bag here for posterity. I may frame it. Then again, I may not.

What is the purpose of the "offset screw"? Man, that manual is vague and hides the details very efficiently. Let's take all the important stuff, make it really small print and then mix it all up in the book randomly. And let's not even address certain compnents, like the offset screw.

Bryan_16

offset screw

has always been off-limits to contractors. Only those with special training are allowed. MHO. Bryan

Unknown

Cool,,,

I was just wondering if it had anything to do with dialing my numbers in a little better. Thanks!

m

Unknown

OK,,,

Called HTP they think the numbers are fine. The offset screw DOES have to do with adjusting CO2 but they feel mine should not need adjusting. They are emailing me an updated in depth explanation of the procedure for setting up the gas so if anyone is interested contact them and request the same from tech support. Now,,, we wait.

Bryan_16

Why aren't the

detailed instructions included? You and I end up doing the r & d on their equipment. They must feel we are totally incompetent. Bryan

Unknown

Apparently,

This is a new issue. If you'd like email me and I'll send you a copy. falade@snet.net

Unknown

The offset screw,,,

per my reading the manual, is only adjusted during low fire if your low fire numbers are bad. Mine are good so adjusting it will do nothing for me. I think I understand why they try to avoid us messing with it. It sounds like it's very touchy and it can cause the valve to start producing positive gas pressure which is a major hazard. Of course, wouldn't it be better for us to know this right at the get go? I have to wonder how many guys have messed with the screw in uneducated attempts to set upv a unit that wasn't performing properly for them. The manual goes fairly in depth on trouble shooting the unit(s). It could use a good proof reader though.

Unknown

Helps a lot!

Thanks! If I'm not mistaken I did see a dab of shellac on it which indicates to me it should not be messed with but I just KNOW somebody out there has and probably in a haphazard manner because they didn't have the correct info. The tech support manual I just got by email does explain it more in depth.

Funny, I went there today becasue he called me this morning to tell me it wasn't working. I went running over there with visions of F09 dancing in my head. Nope, one of my threaded fittings decided to start leaking, it was off on low water pressure. I checked through it anyways. Level and pitch are still good and there's water in the neutralizer so apparently it's draining ok. Once I brought the pressure back it fired right up. Now we wait some more.

I told him I wanted to service it in the spring because I'm real curious as to how it's going to look in there after this season is over.