Girard Tankless Water Heater Trouble

[DNR65]

Hi. I need a little help. I have 2019 Thor Vegas. It has a Girard Tankless Water Heater. The control panel has power and I have propane. The exterior faucet lights the unit and I have hot water. The interior faucets will not trigger the heater to kick on? Thoughts?

[RV_Envy]

That's a head scratcher... I have same issue but no hot water...not even from outside taps

[DNR65]

Originally Posted by RV_Envy

That's a head scratcher... I have same issue but no hot water...not even from outside taps

I figured mine out, low water pressure. Strange it worked outside but not in???? I wish I could help with yours

[javelin]

Always turn off the hot and cold taps on the outside (dog wash) faucet, not just the spray head valve. This is a known cause for allowing hot and cold water lines to mix and possibly reduce the water pressure flowing from only hot faucets. The other thing to check is make sure your winter bypass valves are fully in their Summer positions.



We need more information on the other poster's Girard problem. Did it just start having a problem; does it try to fire but fails to light etc.

[DNR65]

Thank you for the info

[javelin]

I guess regular bypass valves don't necessarily apply to RV instant water heaters unless they are add ons for maintenance or some sort of backflush setup.

[DavidEM]

Originally Posted by javelin

I guess regular bypass valves don't necessarily apply to RV instant water heaters unless they are add ons for maintenance or some sort of backflush setup.

Thor installed the three way valves on my Girard water heater on my new Axis. Old habits die slowly.

David

[RV_Envy]

Yeah, I have 4 valves ( I think)

1 is the big PVC drain
1 is a cold water supply to the water pump
1 is cold water bypass
1 is hot water bypass

I didn't winterize so I closed the PVC drain. Opened the supply and closed both the hot and cold bypass. (Assuming bypass)

Cold Water strong from both city and water pump to all faucets.
Hot Water, nada. Not even a drip.
No sound from Tankless water heater. Doesn't hum. Power and temp set but no activity. Lots of propane.

It's a 2020 Thor Gemini.

Gotta be something small but what da heck I am missing...no idea? Am I missing another valve? But shouldn't the system still hum or light?

Appreciate responses...4th motorhome but first time with tankless..

[Judge]

There must be 100 posts on here about the Girard Tankless Water Heater and recommendations on how to use them properly. The "search" function can be your friend.

Here are the primary issues causing hot water problem in order of most common occurence.

50% of the time the issue is related not enough water flow do to poor water pressure. You need at least 45PSI of water pressure coming into the tank.

30% of the time the issue is people mixing cold water with the hot like they do at home and not setting the thermostat to the desired temperature and then only opening the hot valve for water.

10% of the time the issue is related to construction debris in the water line cause the strainers (screens on the faucets and shower) to become blocked and restrict the flow. There is also a strainer / screen at the water inlet to the back of the unit. This can also become blocked with debris. Thor does recommend removing this strainer in cases where people are having flow issues. The house water system filter is before the tankless so assuming there is no construction debris in the water line coming into the tankless, the strainer should not be be needed.

5% of the time the incoming water flow valve on the back of the unit needs adjusted. When the incoming water temp is very cold, then slowing the flow will allow the water to spend more time in the heat exchanger to heat up enough.

5% of the time it could be one of several other issues such as.... there is an actual problem with the tankless unit.... there is a bad faucet cartridge and it is allowing cold water to leak and mix in with the hot water.... there is a kink or some other blockage in the plumbing restricting flow.

[Judge]

Originally Posted by RV_Envy

Yeah, I have 4 valves ( I think)

1 is the big PVC drain
1 is a cold water supply to the water pump
1 is cold water bypass
1 is hot water bypass

I didn't winterize so I closed the PVC drain. Opened the supply and closed both the hot and cold bypass. (Assuming bypass)

Cold Water strong from both city and water pump to all faucets.
Hot Water, nada. Not even a drip.
No sound from Tankless water heater. Doesn't hum. Power and temp set but no activity. Lots of propane.

It's a 2020 Thor Gemini.

Gotta be something small but what da heck I am missing...no idea? Am I missing another valve? But shouldn't the system still hum or light?

Appreciate responses...4th motorhome but first time with tankless..

I have had two coaches with the Girard Tankless Water Heater and neither of them had a hot water tank bypass.... even though the schematics showed it. I think someone back at HQ is just lazy and reuses one set of schematics whether it is a tank or tankless water heater in a coach.

Anyway..... you said "Hot Water, nada. Not even a drip."

I take it to mean if you open the hot water on any faucet, there is no flow since you say "not even a drip."

If that is in fact the case, you need to check a couple items.

1) Check to make sure the inlet flow valve on the back of the unit is open and allowing water to flow into the tankless.

2) Remove the incoming water line at the back of the unit and check to see of the strainer / screen is plugged with construction debris. While you have it off you might want to make sure you have water coming through that line and into the tankless.

If you don't have a drip of water coming out the hot anywhere then that means there is no water getting into the tankless.

[Bob Denman]

I'd follow the Judge's lead on this...
Once you get the idiosyncrasies figured out: Girards actually work pretty well...

[RV_Envy]

Wow, thanks for your time! Not sure I have that version. I looked and either don't have that flow valve or if I do, can't be reached.

Originally Posted by Judge

I have had two coaches with the Girard Tankless Water Heater and neither of them had a hot water tank bypass.... even though the schematics showed it. I think someone back at HQ is just lazy and reuses one set of schematics whether it is a tank or tankless water heater in a coach.

Anyway..... you said "Hot Water, nada. Not even a drip."

I take it to mean if you open the hot water on any faucet, there is no flow since you say "not even a drip."

If that is in fact the case, you need to check a couple items.

1) Check to make sure the inlet flow valve on the back of the unit is open and allowing water to flow into the tankless.

2) Remove the incoming water line at the back of the unit and check to see of the strainer / screen is plugged with construction debris. While you have it off you might want to make sure you have water coming through that line and into the tankless.

If you don't have a drip of water coming out the hot anywhere then that means there is no water getting into the tankless.

[Judge]

Originally Posted by RV_Envy

Wow, thanks for your time! Not sure I have that version. I looked and either don't have that flow valve or if I do, can't be reached.

Attachment 30591

This is the same Girard Tankless I have..... as a matter of fact my previsous coach was an Outlaw 29H.

You need to be inside the coach to see the back of the unit. The flow control and water hookups will be underneath the kitchen counter. Try taking out the trash can under the sink and looking behind there.

[RV_Envy]

BINGO !!!

Pulled out a drawer in the kitchen and sure enough, there was the valve in the off position. Working perfect, thanks to you!

Appreciated!!!

Originally Posted by Judge

This is the same Girard Tankless I have..... as a matter of fact my previsous coach was an Outlaw 29H.

You need to be inside the coach to see the back of the unit. The flow control and water hookups will be underneath the kitchen counter. Try taking out the trash can under the sink and looking behind there.

[Quint]

Originally Posted by Bob Denman

I'd follow the Judge's lead on this...
Once you get the idiosyncrasies figured out: Girards actually work pretty well...

Got to disagree with this statement, they do not belong in an RV. Requiring 45psi is just unacceptable, many many older or smaller campgrounds are hard pressed to supply that pressure. If you're trying to conserve water while showering and shut off the shower head expect a nice cold run of water for about a 1 minute or so when you turn it back on. If you're trying to do dishes and don't want to keep the water running forget about having hot water.

[Bob Denman]

Originally Posted by RV_Envy

BINGO !!!
Pulled out a drawer in the kitchen and sure enough, there was the valve in the off position. Working perfect, thanks to you!
Appreciated!!!

Glad to see thuis post: congratulations!

[Judge]

Originally Posted by Quint

Got to disagree with this statement, they do not belong in an RV. Requiring 45psi is just unacceptable, many many older or smaller campgrounds are hard pressed to supply that pressure. If you're trying to conserve water while showering and shut off the shower head expect a nice cold run of water for about a 1 minute or so when you turn it back on. If you're trying to do dishes and don't want to keep the water running forget about having hot water.

And I'll politely disagree with your statement. It all depends on the type of camping you are doing.

If you are not doing a lot of boondocking and trying to conserve water (which is my case), the Girard Tankless is great. You can set a temperature, turn on the hot water and you can take a 30 minute shower if you want.

Yes.... some campgrounds have water pressure issues but many do not. If I do come across a campground where I can't get enough pressure, then I will switch over to my fresh water tank for showers.

I've had two coaches with the Girard and I have been very happy with its performance.

[DavidEM]

Let's talk technical for a bit about water hydraulics:

Yes you may need 45 psi to push at least 0.8 gpm (Girrard's spec) through the water heater and outlet fixture, but I will bet the restriction is caused by the fixture not the Girrard.

For example my shower head would sort of dribble either hot or cold and was just on the border of meeting the 0.8 psi spec, sometimes the Girrard would turn on, sometimes it wouldn't. So the first thing that came to mind was trash in the shower head. So I unscrewed the hose from the shower head and found a 3/8" diameter white plastic "button" with three tiny holes in it. I removed the button and the shower head flowed like crazy. This was with the water pump, btw.

So look at your fixtures. Maybe trash has built up in them and requires 45 psi to get enough flow, but if you remove the trash you will get the flow even at much lower pump or shore power pressure.

David

[Bob Denman]

The Truma systems only need .4 gal/min in order to work properly.

[knucklehead]

Originally Posted by Judge

There must be 100 posts on here about the Girard Tankless Water Heater and recommendations on how to use them properly. The "search" function can be your friend.

Here are the primary issues causing hot water problem in order of most common occurence.

50% of the time the issue is related not enough water flow do to poor water pressure. You need at least 45PSI of water pressure coming into the tank.

30% of the time the issue is people mixing cold water with the hot like they do at home and not setting the thermostat to the desired temperature and then only opening the hot valve for water.

10% of the time the issue is related to construction debris in the water line cause the strainers (screens on the faucets and shower) to become blocked and restrict the flow. There is also a strainer / screen at the water inlet to the back of the unit. This can also become blocked with debris. Thor does recommend removing this strainer in cases where people are having flow issues. The house water system filter is before the tankless so assuming there is no construction debris in the water line coming into the tankless, the strainer should not be be needed.

5% of the time the incoming water flow valve on the back of the unit needs adjusted. When the incoming water temp is very cold, then slowing the flow will allow the water to spend more time in the heat exchanger to heat up enough.

5% of the time it could be one of several other issues such as.... there is an actual problem with the tankless unit.... there is a bad faucet cartridge and it is allowing cold water to leak and mix in with the hot water.... there is a kink or some other blockage in the plumbing restricting flow.

We had a 2017 Thor Axis 25.2 with the tankless water heater. I LOVED IT and wish I had one on our 2018 Windsport. I figured out like the other guy said, the best thing to do is adjust the temp. on the control panel to what is comfortable and only open the hot water valve.