Hi all, I just replaced a ventless heater that was busted with a new ventless heater that was purchased at the same place. The previous one lasted about 15 years. This one looked exactly the same like it was the same listed btu. One difference was that you can run on propane or natural gas. There is a knob to turn for you to select which gas you are using. There is also inlets on the bottom for propane or natural gas. Problem is is that after I installed this new ventless heater everything looked good but for some reason the pilot light would not start. I honestly don't even think gas is flowing because I placed a flame near where the gas should be coming out and nothing happened.

I troubleshot this by thinking it was busted so I was going to return and install a new one but that didn't solve the problem either. What am I missing? I did check the gas at the inlet of the ventless heater and that is flowing. The only thing that I wasn't able to check is the manifold pressure. It does state that I should check that in the manual but I didn't think it would be a problem because I am replacing a ventless heater so there should be proper pressure getting to this new ventless heater.

This is the installation manual for the thing:
http://pdf.lowes.com/installationgui...08_install.pdf

Thanks for helping...

 

You’ll have to check gas pressure.

 

How did you do that ??

Natural gas or propane ?
It may take a while for the air to purge out of the gas line.

 

I removed the ventless heater from the pipe and then opened the valve just a tad and heard a hissing sound and plus I could smell it. I quickly shut it off then. That is how I know it is flowing.

It is natural gas. I really don't understand as these lines are not new though. In order to replace the ventless heaters I just used the valve that is located at the ventless heater. Very confusing. I thought this would be a simple swap out.

But like I said, it was working for the previous heater. The previous heater broke because I couldn't turn the manifold valve to the on position any more.

 

Once you replace the heater with a new one...... it could take at least five minutes or even more to purge the pilot line.

 

You’ll still have to check and adjust gas pressure. Gas burning equipment is not plug and play style appliances. And they do not come preadjusted.
Be careful with ventless equipment. There has been a lot of negative pressure out on them, and in some areas they’ve been outright banned due to safety issues. I’d suggest cracking a window or door when you use it, and don’t use it for a primary heat source.

 

The garage I am using it in isn't very tightly sealed. I also have a CO alarm so should be fine. I removed the front cover and took two photos as you can see below.

 

What exactly should I do to test and see if the pressure is ok?

Thanks

 

That tee with the plug is where you’ll take inlet pressure. There should be a plug in the valve for manifold pressure.
You’ll need a gas pressure gauge.

 

Ok, thanks. How do I adjust the manifold pressure? I found the below image in the installation instructions:




I also plan on using this to do the pressure testing:


From my understand I would simply remove the brass fitting on the end of the pressure gauge hose and push the hose onto where it says "outlet" on the gas manifold.

BTW: there are small screws located in the inlet and outlet of that gas manifold.

 

Also from my understand where I circled red is where the inlet and outlet is located on that diagram:

 

So I did manage to test the pressure at the Tee for the inlet and it read around 10 in. W.C. which should be very good. However, I don't know how to measure the Manifold pressure though.

 

The manifold pressure is the outlet.

 

There is a screw located in the outlet BTW. I placed the pressure gauge hose on the outlet and it read zero. I should also mention that I held down the pilot light for 20 minutes and still no spart happened.

Got any idea how I increase the pressure in the manifold as it is zero?

 

Believe it or not the gas heaters still are not working. Called the manufacturer and they said a part was busted. So went to store and got another gas heater and returned this one. Installed it. This one is having the same issue.

 

On page 11 it discusses a "selector valve". Did you confirm that is locked in the NG postion ?