Heatwave

[Stayclearwindowcleaning]

is the heatwave really worth the money. I would like hot water but Dont want LPG. Can't decide

 

[Green Pro Clean Ltd]

I have propane and am happy with it.

Seem to see quite a few second hand Heatwaves cycle through ebay.

I seem to recall a user on here had one and said not worth the money.

 

[Stayclearwindowcleaning]

Thanks for replay. I know lpg is the right way on the price to have hot. Do u know if it's much to the heatwave when it comes to a Service because I was thinking about buying secondhand my local dealer wants £4200 for a 9 kv

 

[Green Pro Clean Ltd]

Thanks for replay. I know lpg is the right way on the price to have hot. Do u know if it's much to the heatwave when it comes to a Service because I was thinking about buying secondhand my local dealer wants £4200 for a 9 kv

Nope, I know nothing about them I run propane.

Personally I would spend £200 on an L5 setup and blow £4k on a world class holiday!

 

[Tuffers]

Thought he was one of our Aussie cousins for a minute :laugh:. Well below freezing here

 

[spruce]

is the heatwave really worth the money. I would like hot water but Dont want LPG. Can't decide

There are only 2 choices to heat water, diesel and LPG. The way I see it is that you have already made that decision. /emoticons/wink.png

The next question is regarding cost and whether you think the extra expense is justified. There are cheaper 1 man diesel heaters running the Webasto 5.2KW Thermotop but in my experience it wouldn't do the job - warm water, yes, hot water, no.

The 9.kw is the best alternative for us but isn't perfect, especially if you are inclined to stop and talk like I do.

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[Stayclearwindowcleaning]

thanks spruce there is a Guy around my way that's got a 5.2 kv and he said the same about the temperature. I tend to stop and speak as well in what respect will that affect it thanks

 

[spruce]

thanks spruce there is a Guy around my way that's got a 5.2 kv and he said the same about the temperature. I tend to stop and speak as well in what respect will that affect it thanks

You asked for it.

Webasto diesel heaters are basically engine preheaters used in cold countries to warm the engine up and defrost the cabin without having to let the vehicle engine idle. They do a good job of doing that.

So what it does is that it starts full bore and warms the water in the engine to about 30 degrees before it triggers the vehicle's heater blower to start warming the cabin and defrost the windscreen. It takes about 30 minutes for vehicle's engine to be warm and the vehicle defrosted. The heater is owner activated by an internal controller - the first press of the button is an activation timer that works for 30 minutes - I think it goes up in 10 minute stages with each press thereafter. The timer can also be preset to switch on at the same time every morning as well.

Should you have the internal fan off then the heater will go into half heat mode at about 74 degrees and will slowly rise to 77 degrees. At 77 degrees the heater will go into its 180 second power down and switch off. ( The 9.1kv heater has a bigger temperature gap between full and half heat mode and the half heat mode is a lower heat output than the 5.2kv so is more forgiving in our application.But its power down period is also 180 seconds - this can't be interrupted.)

Now the user is then told to drive his vehicle longer than 30 minutes to recharge the battery. These heaters use a fair bit of battery power to start up, hence the journey must be longer than the time the heater was on - this is an important bit of information from the user manual.

Now we (window cleaners) come along and adapt the same heater for heating our window cleaning water. We buy a unit that has a small header tank (11 liters) half filled and 1 or 2 (depending on single or twin operator) plate water to water heat exchangers incorporated into the internal heating circuit. The heat exchanger also includes a thermostatic mixer valve which so you can preset the temperature of the water you want at the brush head.

One of the big complaints of Webasto diesel heaters is that they consumer a lot of power when starting up. They can draw up to just short of 20 amps on startup. (20 amps is 4 or 5 Shurflo pumps running all at the same time). Startup usually takes about 3 minutes but the ignition segment with high current draw is probably 30 to 45 seconds. One of the suppliers of diesel heaters recommends that your vehicle is fitted with a second leisure battery for the heater and that you have a split charge relay as well. You start your van and then the diesel heater before you drive to you first customer. This means that the vehicle's alternator is supplying the power needed to start the heater rather than drawing it from your leisure battery. (If your first customer is a long drive away then stop and start the heater along the way.) This supplier also suggests its best to recharge this leisure battery ever night.

Once started the heater needs time to heat the internal water circuit before the water gets hot. A window cleaner drawing heat straight away will slow that down, so will see this as his heater taking forever before any warmth comes through. That's the first house cleaned with cold to luke warm water because you also have to allow time for the water in the hose to be expelled (cold) and replaced with warm

If he has a few houses together then the warm water will eventually start to come through.

If the cleaner stops to talk then the heater will just heat the internal water circuit until it reaches 74 degrees and goes into half heat mode. If you then drive to you next customer you will probably find that the heater has gone into power off mode although the pump is still circulating hot water. You start cleaning your next house with hot water but it quickly goes cold. The heater has sensed that it needs to power up so starts the ignition cycle again. By the time it just gets going you finished cleaning the house and move off to your next house.

Ionics have overcome this stop start by fitting the hot water outlet with a pressure relief valve which is set at 65psi. You clean windows as normal and switch your tap off the pump raises the internal pressure above 65 psi and bleeds the heat back to the tank. This keeps the heat under control. This concept limits the stop start issues, but your water pump runs all the time.

If you have a string of houses together the heater will more than likely keep up with you and provide you warm water to clean with. So a compact round will mean the windie will have more of a chance of using a diesel heater successfully.

Then the windie finds out that he can legally use red diesel in his heater, but he requires a separate diesel tank. Red diesel is half the price of road diesel. Webasto's and red diesel aren't good bedfellows as red diesel creates a lot of soot which turns to carbon, cokes up the burner and heat exchanger of the Webasto and eventually causes ignition failure. Hurricane boast that their diesels heaters work fine with red diesel but one of the service agents says that in proportion, they suffer just as much. Heaters that switch on and off often tend to coke up and servicing is expensive. A search through the boat forums brings up a wealth of info based on personal experiences. (Boats are permitted to run on red diesel and red diesel is all the Marina's sell.)

I set up a test bench a few years ago using a Thermotop connected to 3 water to water plate heat exchangers. The idea was that a 5kw Thermotop would require 2.65kv to heat water through 25 degrees at 2 lpm. The water in my tank was 9 degrees and the maximum I could get at the brush head was 35 degrees.

But the heater had nothing more to give. So where did the other 2.55kv of heat go which should have been enough to run a second pump?

(TBH 35 degrees was more heat than I originally wanted. I just need something above 20 degrees to keep the hoses supple during winter.)

The heater gets hot so some of that will be lost into the surrounding air. The exhaust gas was also very hot, so I'm guessing that the vast majority of the 2.55kv was being sent out the exhaust - 1/2 your fuel bill. So at best my heater was running at just less than 50% efficiency. I don't know the state of my Webasto's internal heat exchanger is as I've never had is apart. I bought it refurbished as the first heater I bought was from a BMW and didn't work due to the Can-bus electronics. I didn't realise that I needed a Thermotop with an analogue pc board and not vehicle specific. (I understand that old Rover and Citroen C8 preheaters will work though.)

The third water to water heat exchanger was going the be connected to a third pump which would be trigger by the thermostatic digital temperature controller. Remember that I noted that a Webasto will kick into half heat mode at 74 degrees. Once the heater reaches that point and you start drawing heat, then the internal circuit will need to drop by about 15 degrees before the burner kicks into full heat mode again.

I would have triggered the controller to switch the pump on at 75 degrees and switch it off at 68 degrees. This I saw was the way to bleed that excess heat off back to the tank and keep the heater running on low heat mode. The pump would also have been wired into a PWM controller so it didn't run a full speed. (BTW the heater automatically switches off after 90 minutes of operation and needs to be switch on again manually. This is for safety reasons).

But I never did any of it.

There is a cleaner in Andover who uses a 5kv Webasto to heat the water in his tank. As far as I'm concerned the jury is still out on this unless you have an insulted tank so heat escape is minimal.

However, this will take ages to warm the water in the tank and the water won't be more than warm.

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The other issue I see is that hot water rises in the tank and we draw our water from the bottom of the tank where the water is cold. Don't be taken in by the heat of his temperature gauge. 52 degrees on the gauge doesn't mean that the water in the tank will be at that temperature. Remember that the gauge started off at 39 degrees so the heater was raising the water temperature by 13 degrees, so would need several 'passes' to get the water hot (at the top of the tank).

Another thing we tend to forget is that all suppliers encase their heater in metal cabinets. These get hot and much heat is lost into the back of the van. PureFreedom are the only ones I've seen who insulate the insides of their heaters to reduce heat loss.

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[Stayclearwindowcleaning]

I think that sums it up Thanks for taking the time to explain it to me it's a lot more than meets the eye thanks spruce

 

[spruce]

I think that sums it up Thanks for taking the time to explain it to me it's a lot more than meets the eye thanks spruce

This is why the average windie who needs hot will use gas as its cheaper and is more instant.

The gas heater most commonly used is an 8 LPM tankless heater which produces 16kw of heat as apposed to the Webasto's 9.1kw.

The down side is that the gas should be switched off at the gas bottle when you drive to your next customer. This is a safety issue. Someone once said that it was legislation in the UK but I've never found anything to confirm that in the search I have done.

There is gas safety legislation in place with regard to catering vans, but is a grey area in the service industry. A roofer will carry a gas bottle in the van, but will generally only use it outside. The RV industry have to put the gas bottle in a special compartment that is sealed to the inside and only accessible from the outside with vent holes through the floor. A caravan has its gas bottle in a compartment on the draw bar, so again, outside the main living area.

I would believe that the best way is to have a gas mounted system properly vented through the roof and an LPG tank either fitted inside or under the body which can be filled at the local LPG garage forecourt.

The heater costs about £100 and a flue will add another £100 by the time you buy a core cutter to drill a hole in the roof. Then there's the gas bottle, to secure, so the overall cost won't be more than £300 - £600 if you go for an LPG refillable tank plus labour to fit.

Yes, this is more expensive, but at least you are making sure that all the t's are crossed and the i's dotted.

Gas is probably the way to go for a single owner operator, but not if you employ staff.

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[Stayclearwindowcleaning]

Going to look in to the lpg side today. Just thought the diesel side of it was better intill u Explained it. Thank u for taking the time to replay

 

[kevinc250]

Going to look in to the lpg side today. Just thought the diesel side of it was better intill u Explained it. Thank u for taking the time to replay

i agree with spruce,the diesel stystems are great when you are working,i like to hear mine start up and run (no silencer so makes a nice whooshing sound-i'm a big kid really)the ionic stystems are as spruce has said are really meant for compact rounds or that large commercial job a fair drive away,

they are a nightmare to keep up with the power side of life and re charging the battery every night is a must,mine has only ever run on esso fuel and providing i have the battery ampage will crack up every time

cost wise they are the same to run as a gas heater l5 or similar,

if you can wire a plug then servicing a 9kw heater is pretty simple its just a case of de coking and cleaning.

if you have the money and the mindset to keep the battery fully charged then a diesel heater is the better option imo

 

[Stayclearwindowcleaning]

Was looking at the l5 yesterday and watched a few videos. By the looks of it they both got there pros and cons.

 

[Stayclearwindowcleaning]

Will it still need charging every night even though it's on a split charger

 

[spruce]

Will it still need charging every night even though it's on a split charger

Yes, its best.

 

[spruce]

Was looking at the l5 yesterday and watched a few videos. By the looks of it they both got there pros and cons.

The L5 heater hasn't the provision for a gas flue. They are 'designed' to work outdoors in the open where the gasses are vented directly into the atmosphere.

There are cleaners who have compromised and fitted it onto the back door and when in use, leave the doors open.

Then there are others who have fitted it on an inside panel close to a door that can be left open. I don't think many have the concept of how dangerous carbon monoxide fumes are, but then again, that's my opinion. I would rather act on the side of caution.

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[Stayclearwindowcleaning]

If the flue was to go through the floor would that be okay. And is this l5 the better 1 to go for thanks

 

[spruce]

These boilers aren't air driven so they can only have a flue through the roof. Hot air rises. These L5 heaters don't have provision to secure a flue to.

On the 8 LPM unit the flue at the top is about 85mm in diamt, so the correct size pipe can be fitted to it.

Look at the top of the heater in this seller's listing and compare it to the L5 heater you are looking at.

8L 16Kw Stainless Hot Water Heater Gas Lpg Propane Tankless Instant Boiler Gift | eBay

Rinnai make a suitable stainless steel roof vent, but I can't see any on Ebay at the moment.

This is similar to the Rinnai flue but one would need to confirm the size of the adaptor/connector included.

Morco D61B Gas Water Heater Flue Kit | Buy now from gasproducts.co.uk

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[Stayclearwindowcleaning]

Thanks spruce u have been a Great help