Bosch 1600H tankless water heater (NG)

We installed a Bosch 1600H (natural gas) yesterday. When we first tried to start it we would get a spark but it would not light (the green light would not come on). After about 10-15 minutes of trying different faucets we now no longer get a spark.

We know it is getting gas. We reduced the gas flow into the unit from 3/4" to 1/2" because of existing pipes from the previous, very old, standard hot water tank. Could this be part of the problem? If not, what else could be wrong?

Thanks!

soonergirl99 said:

We installed a Bosch 1600H (natural gas) yesterday. When we first tried to start it we would get a spark but it would not light (the green light would not come on). After about 10-15 minutes of trying different faucets we now no longer get a spark.

We know it is getting gas. We reduced the gas flow into the unit from 3/4" to 1/2" because of existing pipes from the previous, very old, standard hot water tank. Could this be part of the problem? If not, what else could be wrong?

Thanks!

Click to expand...

This unit uses water flow to generate a spark. Low flow through the unit could be an issue and I would suspect the low flow of gas as another possible issue. Page 3 of the manual states 3/4" gas line as a requirement. Page 11 states "The minimum diameter required for any appliance connector used is ¾ NPT."

One other note from page 19...
Confirm that there is an adequate flow rate. With
the temperature adjustment knob on the unit
positioned all the way clockwise, a 1/2 gallon per
minute (GPM) flow rate is required for heater
activation. Fully open a hot water faucet and fill a
quart container. If the container fills in 30 seconds or
less, the flow rate (1/2 GPM) is sufficient to activate
the water heater.
NOTE: When the dial is turned all the way
counterclockwise, a flow rate of 1.1 GPM is required
for heater activation.

Aside from the questionable worth of any tankless water heater, you never should mess with the manufacturers installation instructions and especially with gas. It goes without saying that you had no permit and have no intention of having it inspected, so what you have is anyone's guess. If you're lucky it won't go boom!

soonergirl99 said:

We installed a Bosch 1600H (natural gas) yesterday. When we first tried to start it we would get a spark but it would not light (the green light would not come on). After about 10-15 minutes of trying different faucets we now no longer get a spark.

We know it is getting gas. We reduced the gas flow into the unit from 3/4" to 1/2" because of existing pipes from the previous, very old, standard hot water tank. Could this be part of the problem? If not, what else could be wrong?

Thanks!

Click to expand...

You most likely still have some air left in the gas line. You have to bleed that air out of the heater before the gas will get to the burners.

Helmet secured. Awaiting orders Captain.

Whatcha think NH Master...
It sounds to me like the Dilithium Crystals are shakin too hard and it's gonna be nothing but tribble...

Hey Red, nice Pex post on ****. Note my incredible restraint on the subject.

You must have your helmet strapped down tight tonite.
Either that or the big sticks are all covered in snow...

nhmaster said:

Helmet secured. Awaiting orders Captain.

Click to expand...

Maybe we should put together a kit we send out to these DIYer gas installations...

Bunk beds, a square, purple cloth, five dollar bill and three quarters, black shirts and sweat pants, brand new black-and-white Nike athletic shoes, and armband patches reading "DIYer Gas Installation Team" for each family member.