Adjustable High

Adjustable High

I recently had a high efficiency furnace installed, what is the reason it needs a fresh air intake?

The furnace sometimes has a problem firing and the installer(not hvac) thinks it is not getting enough air to fire. It eventually does fire. He removed a plug on the side of furace (about the size of a hockey puck) to allow more air in. It seems to work better but this is not how it is supposed to work. The intake is 3" pvc, 2 elbows, 18 ft long. He also measured gas pressure at two places. He thought the gas pressure coming in may be too high(12). he adjusted the internal pressure to specs. The intake pvc is not clogged. But if you remove it at the furnace it seems to fire normally. He seems to think that removing the plug is good enough. I want to make sure this is not bad for furnace and safe to run this way. Would an adjustable gas valve fix it?
Also, the gas water heater is still vented into chimney, it is in center of house. I have a slate roof so it is difficult to access chimney. The chimney has an elevated cover.
Any suggestions are appreciated.

The new high effiency furnaces need to draw their combustion air from outside the house. it's All About the negative pressure like mentioned above.And also as a safety to keep the combustion sealed from the ambient air in the house.
And like redbird mentioned your intake piping may be too restrictive, and may need to be replaced with a larger diameter pipe.

But everybody has overlooked the obvious.
Have you looked at the intake pipe outside?
It could be that the exhaust and intake are too close together causing the furnace to recycle the exhaust gases.
Since there is little to no O2 left in the exhaust it can cause the symptoms you've mentioned.
The exhaust should be turned up and away from the intake or straight out from the house and the intake should be turned down, to keep them at a minimum of 18" apart.
Check your manual to find out how far apart they should be and how they should be terminated.
Is it blocked by something?
Sucked up leaves etc etc.
A couple of leaves in the pipe can restrict it just enough without making it appear blocked.

I made a service call on a furnace one night for the exact same problem as yours and found the guys 6 yr old kid had stuffed a plastic bottle down into the pipe with a stick.

Just a couple more ideas for you to look at.

Do mortgage brokers receive a higher commission for delivering adjustable rate mortgages to the banks?

I'm a CPA but am not entirely sure how the mortgage brokering process works. I've received some sketchy information in the past indicating to me that the higher the rate is, the more of a commission the bank pays to the broker for bringing them the loan. I believe the exact terms are when the rate is above the bank "par rate". Now I've heard that if the broker brings the bank an adjustable rate loan that the broker receives and even higher Commission. Is this true?

Thanks,
Craig R. Fechter, CPA

It is true that the broker gets paid for an above par rate but not true that they are paid more for an adustable rate. The reason that some brokers and lenders for the matter push an adjustable rate is that it is lower than a fixed rate and "easier to sell". It's unfortunate but many loan officers are just sales people and will sell what they think is easiest instead of what is best for you.

Fully Metallic Adjustable Homemade Rotary Tattoo Machine (PART I)