Heated Wet Bay?

[TTD]

If I understand correctly, the dial in my wet bay controls the heat going to my wet bay.

My questions are:

Is this a forced warm air situation (from my Aqua Hot), or is it electric heat tape on the pipes and holding tanks.

And 2 - what about the huge gaping holes where the black hose goes out and the water comes in? Seems to me it would be impossible to heat that area with those holes letting so much heat out?

[Mr_D]

On my Magna the wet bay is heated by the AquaHot. The thermostat is behind the access door for the filter. The ports have screw in covers when not in use.

[smlranger]

My Allure has a small Aqua Hot heat exchanger mounted near the top of that bay. There is no fan. We've not had any issues on our current trip with anything freezing up in that bay and we've been in temps as low as 18 at night. The pump which is mounted on the floor of the bay is the most vulnerable. I do have a trouble light with 75 watt bulb that I can place near the pump but have not used it recently. If it is cold enough to disconnect my water and sewer hoses, I do screw the plugs into those holes.

[TTD]

Yeah... that was dumb. It makes sense to unscrew the water/sewer connections if it's that cold.

Thanks!

[TTD]

OK... my coach needs to sit in Massachusetts until the end of November so I am closely watching the weather each night as my coach is not winterized. The average night temps are usually above 32 degrees, but can touch below freezing here and there so I want to be prepared.

I asked a similar question before but I think I got conflicting responses as to how I should set my inside controller?

Things I know... (or think I know):

1 - the heat exchanger that is in the wet bay is part of my back loop, which includes my bedroom and rear bathroom. It is controlled by the small dial in the wet bay.

2 - this loop is on Zone 3 according to my inside control pad, but it correlates to Zone 2 on the Aqua Hot unit itself. (Zone 2 on my inside controller seems to activate my Middle Heat Pump/AC unit)

My coach is attached to 50amp at my home.
My plan is to leave the AquaHot Electric Switch to ON.
Turn on Zone 3 at the control pad and set the inside temperature to the lowest (45degrees).
I have the dial in the wet bay turned to maximum - which I believe is 40degrees?

Is this the correct way to do this?

[smlranger]

Tony, I would not trust the electric element only to provide sufficient heat. I have the 450DE01 Aqua Hot and the electric element provides little heat when any of the zones are running. I leave both the electric and diesel switches for the Aqua Hot turned on.

I set both zone 1 and zone 3 to 'gas heat' (that is how my T stat refers to the diesel fired heat). I usually set the temps to 45F if I am just wanting freeze protection. I set the rotating knob in the wet bay to something between 32 and 40F.

[TTD]

Hmmm... I will have to compare my heat on both ELEC and DIESEL. I know it gets hotter faster on DIESEL, but if I recall from last year, the ELEC worked fine once the unit was fully warmed up.

However, this brings up another question.

On my controller, if I set a zone to ELEC, then the matching zone's Heat Pump on the Roof Air conditioner turns on.

If I set it to GAS, then the Aqua Hot comes on (regardless of whether the Aqua Hot is on ELEC or DIESEL. )

Is that not how yours works?

[Mr_D]

Recovery time is too long and heat output is too low when using only the electric element to work in low temps. For the last three years I've turned my 600D electric elements on low (only one of the two elements are on) and turn on the burner. Set the thermostat for 45° in all three zones, open cabinet doors and place a couple small fans to circulate air in the cabinets that have plumbing in them.

[Mr_D]

Originally Posted by TTD

Hmmm... I will have to compare my heat on both ELEC and DIESEL. I know it gets hotter faster on DIESEL, but if I recall from last year, the ELEC worked fine once the unit was fully warmed up.

However, this brings up another question.

On my controller, if I set a zone to ELEC, then the matching zone's Heat Pump on the Roof Air conditioner turns on.

If I set it to GAS, then the Aqua Hot comes on (regardless of whether the Aqua Hot is on ELEC or DIESEL. )

Is that not how yours works?

Yes, you need to set the thermostat to gas. Setting to elec turns on the heat pumps.

[TTD]

Originally Posted by Mr_D

Recovery time is too long and heat output is too low when using only the electric element to work in low temps. For the last three years I've turned my 600D electric elements on low (only one of the two elements are on) and turn on the burner. Set the thermostat for 45° in all three zones, open cabinet doors and place a couple small fans to circulate air in the cabinets that have plumbing in them.

Thanks!

Any thoughts on leaving the heated tile floors on? Almost seems like that would send heat down to the bays too? My mid-bathroom heated floor seems to be directly above the holding tanks, etc.

[BrianGlenn]

I have not used any heat in my coach when it is above freezing in the day - 40F or so - and when it "touches" down below freezing in the night times. There is enough mass in the coach (floors, frame, walls, water in the tanks, etc) to prevent the wet bay from reaching freezing temperatures and freezing water lines/aquahot.

Where it stays below freezing in the day and night I leave the Coleman thermostat set on gas, turned down to lowest setting, electric switch on, diesel burner off. The fans will turn on inside the coach the circulation pumps will turn on and circulate boiler fluid to wet bay exchanger.

I have run a remote WIFI enabled temp sensor in plumbing bay (near water pump) that I can read on my iPhone and I have always been above 32F, even when it was 20-25F at nights and 30F at days.

The electric heat floor elements will add some heat to the coach, and some will support heating wet bay - I cannot estimate though..... And I am a Chemical engineer and have done many years of heat exchanger design calcs...lol But no heat transfer rates from electric tiles into a wet bay.......lol.

Brian

[TTD]

Originally Posted by BrianGlenn

Where it stays below freezing in the day and night I leave the Coleman thermostat set on gas, turned down to lowest setting, electric switch on, diesel burner off. The fans will turn on inside the coach the circulation pumps will turn on and circulate boiler fluid to wet bay exchanger.
Brian

Perfect!

This is what I did last night and my remote temp sensor said all was good.

I agree about the mass of the coach too! On other nights when I did not turn anything on, I thought my remote sensor was reading wrong because my unheated bay was staying well above the outside temperatures.

[BrianGlenn]

Originally Posted by TTD

Perfect!

This is what I did last night and my remote temp sensor said all was good.

I agree about the mass of the coach too! On other nights when I did not turn anything on, I thought my remote sensor was reading wrong because my unheated bay was staying well above the outside temperatures.

Yup - thats why a 5 gallon bucket of water will not freeze solid for about 24-48 hours of below freezing - Ive put my outside inline water filter in a 5 gallon bucket of water and never had problems.... The mass of water has a fair amount of "sensible and latent" heat.

Brian

[TTD]

Originally Posted by BrianGlenn

The mass of water has a fair amount of "sensible and latent" heat.
Brian

Agreed on the large volume places...I guess my fear is the areas that have only a small amount of water might freeze and cause a crack.

As a backup indicator... next to the water pump, I leave a small bottle of drinking water with only an inch of water in it. I check that once a night to make sure it has not frozen.

So far, so good.