1996Lance water heater issue, new regulator needed?

[calstar]

My 1996 Lance Squire has been sitting unused for several years due to health issues, trying to get it back in good condition. Water heater model Suburban SW6PR pilot was not lighting so I replaced the thermocouple unit(see pic below). Now the pilot lights easily but when I turn the valve to the on position the flame is far from the "jet engine" appearance or sound, actually it scared me(enough so I don't want to ignite again) as the flame was a very big soft billowy one that extended back out and up of the combustion chamber. Is there something I'm missing, does this mean a new regulator? In the second pic you can see a large slot head screw just to the right of the temp control setting dial, is this an adjustment screw?Sorry but I'm unable to remember what was going on several years back. Thanks

 

[CharlesinGA]

Gas regulators do go bad. Have you tried the stove or the fridge? do they work properly? How much gas do your LP cylinders have in them?

Charles

 

[Kirk]

If you would like you can get a copy of the service manual for your water heater and download it. The SW6PR is one that has the pilot but also an automatic relighter and instructions for lighting the pilot can be found on page 11 of the manual. If the flame is outside of the combustion chamber, you are wise not to try and use it. I am wondering it there is something in the exhaust flu for the combustion chamber that is partially blocking it? The mud dobber is notorious for building nests in propane appliances so if I were you the first thing that I would do is to clean that flu to make sure that there is no obstruction. While it is possible that the propane regulator has failed, I wouldn't expect that to cause the flame to be outside of the chamber as you describe. It sure wouldn't hurt to get the supply pressure or have it done as it should be 11" of water column by manometer.

 

[calstar]

. I am wondering it there is something in the exhaust flu for the combustion chamber that is partially blocking it? The mud dobber is notorious for building nests in propane appliances so if I were you the first thing that I would do is to clean that flu to make sure that there is no obstruction. While it is possible that the propane regulator has failed, I wouldn't expect that to cause the flame to be outside of the chamber as you describe.

Thanks for the manual link, I read it all and looked at the diagrams but nowhere did I see the flue location, any ideas where to look? The only reference on the parts list(see below) is #4 back flue connector, #5 front fluid connector. There does not appear to be anything to clean/clear, no exhaust ducting to outside the heater box so....? Posted this pic again, which shows the back flue connector but no sign of any exhaust duct.

 

[calstar]

Gas regulators do go bad. Have you tried the stove or the fridge? do they work properly? How much gas do your LP cylinders have in them?

Charles

The fridge hasn't worked on LP since i bought the Lance 5yrs ago, the stove seems to work fine, burners might be a little low when on high. Propane bottle is at least 1/3 full, the propane regulator at the bottle is brand new.

 

[CharlesinGA]

Note that the round fire tube is divided. The divider goes back a ways and the fire and air is drawn in the lower part, turns around at the inner end and exits out the upper half of the same tube. Basically one tube that is dead end in the tank, divided by the horizontal plate.

This is not at all like an Atwood or Dometic which has a U shaped fire tube passing thru the tank.

Use compressed air to blow out the tube and the gas tube and orifice, Never use metal wire to clean the gas jet.
I'm assuming you have the remainder of the exhaust baffling (item #5 on page 33 of this service manual)(or item #5 in the attachment below) and simply had not installed it at the time the pic was taken.

Post a pic of your new gas regulator. What brand is it? It sounds as if you do not have sufficient gas pressure.

Charles

 

[calstar]

Note that the round fire tube is divided. The divider goes back a ways and the fire and air is drawn in the lower part, turns around at the inner end and exits out the upper half of the same tube. Basically one tube that is dead end in the tank, divided by the horizontal plate.

This is not at all like an Atwood or Dometic which has a U shaped fire tube passing thru the tank.

Use compressed air to blow out the tube and the gas tube and orifice, Never use metal wire to clean the gas jet.
I'm assuming you have the remainder of the exhaust baffling (item #5 on page 33 of this service manual)(or item #5 in the attachment below) and simply had not installed it at the time the pic was taken.

Post a pic of your new gas regulator. What brand is it? It sounds as if you do not have sufficient gas pressure.

Charles

Thank you. Yes I have part #5, not installed at time of pic. I will use compressed air tomorrow,. When you say gas tube and orifice do you mean the bronze color tube in pic below and the orifice entering it(part 19 and 43 in the parts schematic)? The regulator is a Flame King, although its a 2 stage but I'm using it with only one tank, is that an issue for pressure? The regulator was only $40 so probably not the best, if there's a chance it not good I'll get a better one, the burners don't seem to have adequate pressure on the high setting, if so that may indicate the water heater is experiencing the same thing.

 

[Gary RV_Wizard]

A better bet is that there are rust flakes and/or insect nests in the burner tube, disrupting the normal mixing of air and propane. Clean it out good.

 

[Kirk]

 

[CharlesinGA]

When you say gas tube and orifice do you mean the bronze color tube in pic below and the orifice entering it(part 19 and 43 in the parts schematic)? The regulator is a Flame King, although its a 2 stage but I'm using it with only one tank, is that an issue for pressure?

Item 19 has the orifice in it, where 43 is screwed in. You would have to unscrew the gas line (carefully) to be able to blow thru the orifice. But, yes, that is what I was referring to blowing air thru. Also into the large tube that the flame is projected into. You should be able to see inside there with a bright light to see if there is anything major, such as a nest or other blockage.

Personally, I am not fond of the Flame King gas regulator, however you really need a manometer to check the gas pressure, if you can find a port to tap into easily.

Charles

 

[calstar]

I took the burner assembly off, blew it and the combustion chamber(pic below) with compressed air, both were extremely clean before I usde the air, it was good to do it anyway. Before using the air I blocked all the line openings(except of course on the burner assembly) so no chance of any debris entering. I ordered a digital manometer this morning, it'll arrive tomorrow, i'm not going to attempt lighting it until I do further testing, like I said before that billowing flame scared me, don't want the camper to catch fire!. I'll test the stove top first, if its ok seems like it narrows it down to the heater regulator, going to google search to get some idea on test methods.

 

[calstar]

PUZZLING manometer results. i
In trying to get my water heated working again, thought I should check the overall system for leaks as a starting point, I would then check the wc at the inlet line next to the heater regulator as a way to test the regulator if its good or bad by isolating it. I received the Measureman Manometer today, first pic is of the setup testing for pressure and leaks, second pic is of initial pressure reading after following directions: propane off, meter installed, propane on for 10 seconds+-, propane off. The reading is 11.5wc(good range), I then bled it down to 8wc and set a timer for 3 minutes, the pressure reading increased, I repeated this procedure several times and the pressure always increased, third pic is typical pressure increase from 8wc in a three minute period. The last pic is the wc reading after approximately 25 minutes, 2.5"wc increase. When repeating the test the initial pressure varied +- .5 wc, don't know if they should all be exactly the same or is this within spec?

I think the manometer is bad, what else couldn't be? Any possible reason the pressure could increase? I was sitting inside near the open front door when it was delivered on my porch, I heard a noticeable thud when the guy put it down, as in not set down gently. so there is that.

edit: just checked the pressure as shown in the last pic and it remains the same after about 1 hour, no up or down.

 

[RayIN]

The 11" WC is set/measured while the burner is operating, when the burner is shut off the WC will increase a bit. The minimum is 10"WC.

 

[calstar]

Asking this question again as I've searched the net but didn't find an answer, is the slot head screw on the regulator a pressure adjustment screw, don't know what else its purpose is. thanks

 

[calstar]

The 11" WC is set/measured while the burner is operating, when the burner is shut off the WC will increase a bit. The minimum is 10"WC.

Not that utubers always know what they are doing, but all i've watched do it the way I explained I did it. Do you mean I should have one burner going while the other is connected to the gauge, then turn the propane off? Why isn't the test valid the way I did it for the leak test, why is the pressure increasing instead of decreasing, if you know of some posting or vid that explains it please tell where I can find it. thanks

 

[RayIN]

Not that utubers always know what they are doing, but all i've watched do it the way I explained I did it. Do you mean I should have one burner going while the other is connected to the gauge, then turn the propane off? Why isn't the test valid the way I did it for the leak test, why is the pressure increasing instead of decreasing, if you know of some posting or vid that explains it please tell where I can find it. thanks

Don't take my word for it, ask a LP furnace installer. I had a large mechanical firm install a new furnace last year. After installation the tech set LP pressure to 11" while the furnace was running. A tech returned a month later to double check the installation and he re-checked LP pressure while furnace was running.
Quote:

LP or Propane Gas Appliance Operating Pressures in WC, millibars, Pascals, PSI or ounces of pressure​

A common operating pressure for liquid petroleum or LP gas appliance is 10" - 11" of water column (WC) or re-stating this in equivalent measures, that's 27.4 millibars or 2491 - 2739 Pascals or Pa, or about 0.36 - 0.40 psi or about 5.78 to 6.36 ounces of pressure per square inch.​

reference:LP Gas, Propane Gas, & Natural Gas Pressures & Pressure Settings​

The minimum WC pressure is 10"WC= .361 psi. operating pressure is 11"WC= .397 psi.
re: slot-head screw; some LP regulators are not adjustable. I'd assume that slot-head screw is covering the measurement port, and the star-head is the adjustment screw.
re: Increase in pressure, this LP handbook beginning at page 40, states when pressure increases the supply tank valve is not closing completely.

 

[Kirk]

is the slot head screw on the regulator a pressure adjustment screw,

Your answer is no. The device you are looking at is the propane control and the pressure is controlled by the regulator back near the propane tank/bottle. That screw slot is probably the pilot light adjustment.

 

[calstar]

Don't take my word for it, ask a LP furnace installer. I had a large mechanical firm install a new furnace last year. After installation the tech set LP pressure to 11" while the furnace was running. A tech returned a month later to double check the installation and he re-checked LP pressure while furnace was running.
Quote:

LP or Propane Gas Appliance Operating Pressures in WC, millibars, Pascals, PSI or ounces of pressure​

A common operating pressure for liquid petroleum or LP gas appliance is 10" - 11" of water column (WC) or re-stating this in equivalent measures, that's 27.4 millibars or 2491 - 2739 Pascals or Pa, or about 0.36 - 0.40 psi or about 5.78 to 6.36 ounces of pressure per square inch.​

reference:LP Gas, Propane Gas, & Natural Gas Pressures & Pressure Settings​

Thank you for the clarification. I've also watched a vid with a hvac tech installing a large gas fired boiler and part of that was adjusting the pressure using an adjustment screw in the supply line. In the comments section of the vid several other techs said he needed to adjust pressure when the furnace was running and he agreed, you're correct. To the best of my limited knowledge there is no pressure adjustment screw anywhere on my Lance LP system.

The test I performed was to determine the line pressure in the camper system as well as if any leaks were present, not to adjust the operating pressure of the stove. Is there someway to test for leaks in the system with any of the LP appliances running? Seems like with an appliance running its operating pressure would hide/negate any leaks in the system, isn't a leak determined by testing a closed system under pressure monitored over a period of time? For instance residential gas systems are tested for pressure leaks with the system closed with no appliances operating.

Regarding the pressure increase possibly being caused by a faulty supply tank valve I hope that is not the case as it's a brand new horizontal tank purchased a few weeks ago when I bought the regulator. Am I correct in assuming I can test the supply tank valve by disconnecting it from the regulator and with it closed testing for LP tank valve with soapy water? I will test that later this morning

I greatly apprciate your input, please do not think I'm trying to say I know more than you, that is definitely not the case(I'm newbie regarding rv systems), I'm only trying to understand how to operate and check the Lance pressure so I can fix my water heater. Thanks again for the input. Brian

 

[Gary RV_Wizard]

Your LP gas regulator was factory adjusted for 11" W.C. and the adjuster then sealed at the factory. You could maybe get the sealer plug out and change it, but regulators aren't terribly expensive so it's smarter to replace it if in doubt.

And as Kirk stated, the control in your photo is NOT the regulator. It's a heater temperature control valve, probably like this one.

 

[calstar]

This link will lead you to one of the numerous vids(I watched many) on testing for pressure and system leaks, they are all nearly identical and what I followed to do my test, the appliance is not ignited. He also says a small increase in pressure when doing the lock down pressure test is normal(he doesn't say how small) do to LP expansion from environment temperature, as is visible on the manometer he's using, that my explain the pressure increase I noted in an above post.

In this particular vid he states you can also test for a supply tank valve leak by releasing the pressure on the manometer and leaving it attached as you did when doing the test, with the supply tank valve closed if the manometer shows an increase the tank valve is bad.

Comments and advise are always welcome.