Bosch Vision 300 heating problem

[The Rookie]

I have a Bosch Vision 300 gas dryer. Converted to LP with factory parts.  

It has worked perfectly until now.  I have changed the gas supply to a fresh tank and still the flame won't stay on.   When I start the dryer I can hear the burner ignite but he it goes out and never starts again.   I am thinking that the high limit thermostat may have gone bad.   I don't think it's the heating element because I can hear it ignite and i put sounds the same as it always has.  And everything else works fine so I don't think it's the control board.   I don't know anything about appliances but with guidance can fix anything  so your help is appreciated

 

I need advice on this this before I start tearing the back off and taking things apart.  I installed the LP conversion myself with factory instructions and it has all worked perfecty for ove 3 years.

[The Rookie]

I posted this question ten days ago and almost 50 people have viewed it.   So far nobody has come forward with any help or suggestions or comments

Is there no one knowledgeable or otherwise willing to help?  Isn't this the purpose of this resource?

[Hiroshi]

We need some specifics: the model number is ALL important.

Most gas systems with no/poor airflow will shut down shortly after ignition.

[16345Ed]

Maybe if you provided an actual model number someone could help?

 

[16345Ed]

1 minute ago, Hiroshi said:

We need some specifics: the model number is ALL important.

Most gas systems with no/poor airflow will shut down shortly after ignition.

Yes, even bad valve coils could present this way. 

Hi-limit, not as likely. 

You can try disconnecting vent at rear of unit and trying to run a load. If problem persists you've at least eliminated external air flow as an issue 

 

 

[The Rookie]

The model number is in the title. Do you need a serial number ?

[The Rookie]

Thanks. For the input. As I said I am a rookie. But I did include the model number in the Title of the post.   I will try the suggestion and disconnect the outlet vent to check blockage 

[16345Ed]

I'm sure it says that on control panel. But I don't think it's a model number   

Now open door and look around for model number, usually on door frame or jamb. 

[16345Ed]

Something like this...

WFVC3300UC

[The Rookie]

Thanks 16345Ed. I appreciate your guidance. 

 

Here is the Real model number WTVC3500UC/09. FD8911. 300380

 

[16345Ed]

There ya go!

now let's eliminate external exhaust issue  by unhooking vent on back of unit and testing. 

 

[The Rookie]

Ok I will do that next week. I am going out of town and it will have to wait.  I am fairly sure there is no blockage but I will check it and get back to you next week. 

 

Thanks for your help. 

[Koi Guy]

Indeed check for proper air flow.

If the dryer heats initially upon start up when it is cool (ie- has not been in use for a couple hours), but then cycles off and does not heat for an extended time period, or never heats again- I would suspect the gas valve coils to be failing. On the gas valve itself are two coils that when energized will open the valve. If even one coil is failing the gas valve will not open- therefor no flame and no heat.

Replacing gas valve coils is very common and often a good start for the DIY'er as they are easy to install and quite inexpensive. You can find plenty of vids on YouTube for this repair.

You mentioned "tearing the back off and taking things apart"- this unit is designed to be serviced from the front and taking the back off is a mistake and is considerably more effort- although even from the front this unit is not easy to service. 

I looked up the gas valve coils and oddly enough did not find them sold seperately, and only affered as coming pre-installed with the gas valve itself- quite expensive. BUT- those coils sure look like most coils and I would look at using Whirlpool coils as I find them very reliable. Whirlpool Part # 279834.

So without going crazy on this quite yet, I'd check airflow and then proceed with coil replacement.

[16345Ed]

11 hours ago, Koi Guy said:

Indeed check for proper air flow.

If the dryer heats initially upon start up when it is cool (ie- has not been in use for a couple hours), but then cycles off and does not heat for an extended time period, or never heats again- I would suspect the gas valve coils to be failing. On the gas valve itself are two coils that when energized will open the valve. If even one coil is failing the gas valve will not open- therefor no flame and no heat.

Replacing gas valve coils is very common and often a good start for the DIY'er as they are easy to install and quite inexpensive. You can find plenty of vids on YouTube for this repair.

You mentioned "tearing the back off and taking things apart"- this unit is designed to be serviced from the front and taking the back off is a mistake and is considerably more effort- although even from the front this unit is not easy to service. 

I looked up the gas valve coils and oddly enough did not find them sold seperately, and only affered as coming pre-installed with the gas valve itself- quite expensive. BUT- those coils sure look like most coils and I would look at using Whirlpool coils as I find them very reliable. Whirlpool Part # 279834.

So without going crazy on this quite yet, I'd check airflow and then proceed with coil replacement.

Sound advice 

[The Rookie]

Ok guys. I have pulled the dryer out and disconnected the vent. There is no blockage and a strong flow.  Now I don't get any light off of the burner though. I checked the propane tank. It has gas and the valve is full open.  I even out some clothes in the machine in case it has a sensor that won't allow the heat to come on if the drum is empty

 

what should I check next 

[16345Ed]

Read Koi Guy's post

[The Rookie]

Ok I will proceed with koi guys suggestion 

thanks 16345Ed

[The Rookie]

Ok so I removed the front cover and pulled both coils. I used my multi meter and the the needle moved when I touched each contact so I conclude the are both fine. Should I still replace them or should I just buy an entire new gas valve assembly. Which looks like it would be a lot more difficult to replace 

Are the numbers on top the part number and can I use any similar looking gas valve solenoid?

[The Rookie]

Oh. Also I started the dryer and the heating element does come on but since the gas doesn't come on it just shuts off again 

[The Rookie]

Another thing. The igniter comes on and the goes off when there is light off. But keeps trying about every 40 or 45 seconds. Is it safe to use the dryer like this to air dry the clothes or will it cause further harm 

[The Rookie]

IShould I go buy and replace the  coils with the Whirlpools coils?  The only OEM parts for the Bosch as mentioned by you guys earlier is to buy a whole new gas valve assembly for about $140

i tested to see if power is getting to the coils by using my voltmeter to read power at the plug when a starting a cycle.  Each connector tested ok for getting power. And since the coils also test for continuity I don't think they are the problem. 

Also since I am getting power at each cinnector for both solenoids I think that the other sensors are probably ok also. But i am still not getting ignition and no gas is flowing. Since each pin cinnector is getting a reading at the start of a cycle I have concluded that the other components are working. When I disconnected the gas feed line at the gas valve and turned on the gas nothing happened. 

I then went outside and disconnected the hose from the propane tank regulator and again nothing. I have purchased a new regulator and will connect it in a few days when get some more time   I think that is the problem since with the new regular connected but without connecting the hose i did get gas flow 

[Tim M]

Gas valve coils are only 15 bucks for the pair.  It is very, very unlikely to be the valve itself, especially since it opens sometimes.  If they look like the Whirlpool coils, they are the whirlpool coils.  I think I had the same situation years ago where they would work intermittently.

Gas Dryer Problem Solver

http://fixitnow.com/wp/2002/10/15/appliance-tip-of-the-day-gas-dryer-problem-solver/

 

Gas Dryer Diagnostics

http://fixitnow.com/appliantology/gasdryer.htm

 

Diagnosing and replacing the gas valve coils in a gas dryer [video]

http://fixitnow.com/wp/2012/04/27/diagnosing-and-replacing-the-gas-valve-coils-in-a-gas-dryer-video/

 

Burner Operation in a Gas Dryer

http://fixitnow.com/2004/11/appliance-repair-revelation-burner.htm

[The Rookie]

Thanks Tim. I wasn't sure about the coils if the whirlpool would work or not. They do look the same and are available locally. I will take the old ones to the store and compare then buy unless I have concerns .

I will follow your advice

[The Rookie]

Hello everyone

 

Good news. I have solved the problem.  I want to first and foremost thank all of you for your help and suggestions I certainly learned a lot

in the end I found the gas valve was not getting any gas. The coils tested fine and all other sensors tested ok.  I disconnected the gas line and there was no gas getting to the gas valve.  Remember this is an LP conversion running from a 20lb propane tank.  When I disconnected the gas line coming from the regulator and turned on the valve on the propane tank I got zero flow from the regulator output side.  I bought a new regulator and reconnected and leak tested everything. Now it works fine. 

Job done.

Thanks again 

you guys are terrific 

[Tim M]

Good work.  I hadn't remembered you were on a tank.  Anyway, one of the valve coil videos or articles should have told you to listen for the two clicks of each one opening.  That might have helped if we thought of it before.