hitecsa a/c

[Latte]

Evening all,

Is this common ?

Hitecsa A/C (Yeah ive never heard of it before either)
Located in a loft space of a shopping centre, only access is a small hatch only just big enough for a fat ####### like me to get in. ducted a/c system with everything in loft and the condenser mounted up against outer wall.

unit suffering from HP problems, tried blowing from the inside with OFN to clear but still high, looks like to only way to clear it is to take the outer airvents off the side of the building to get to it to wash. Must have put the system in then built round it.

Is this a common practice or am i unlucky enough to get one the only ones out there

Regards

Latte

[glenn1340]

Nope, I had the same problem the other week. I had to cut some roof trusses away (after getting the ok from the client) to enable me to remove a fan cover. I was told the builders DID build the roof around the ducting.
I `spose some builders are like salesmen: do anything to get the job done or win the order

[Greengrocer]

Evening all,

Is this common ?

Hitecsa A/C (Yeah ive never heard of it before either)
Located in a loft space of a shopping centre, only access is a small hatch only just big enough for a fat ####### like me to get in. ducted a/c system with everything in loft and the condenser mounted up against outer wall.

unit suffering from HP problems, tried blowing from the inside with OFN to clear but still high, looks like to only way to clear it is to take the outer airvents off the side of the building to get to it to wash. Must have put the system in then built round it.

Is this a common practice or am i unlucky enough to get one the only ones out there

Regards

Latte

If those louvres are intake & discharge it looks to me like some recirculation might be taking place. Is the dischaarge the larger linnear slot & intake the smaller louvres? If so the warm air in cooling mode could be risiing & getting pulled into the intake above. This might also be affected by a prevailing wind. Get a temp probe on the inlet louvres & compare to ambient temps.

[Brian_UK]

One consolation though, at least it near the ground ;)

[Latte]

The intake is the large grille on the side of the building, the outlet being on top. The outlet grilles are pointing away from the building but there is such a suck on it im sure there is some short cycling. The Intake grilles were completly blocked, ive cleaned them out as best as poss but if they were like that im dreading what the coil is like. If the grilles arnt that heavy it doesnt look too bad of a job but ive said that many times before and look what happens

Regards

Latte

[back2space]

Is there no pre-filter after the air intake louvres? Have you cleaned these... I know you said you have cleaned the air intake but is there anything after this between that and the coil?

I reckon dirty coil/filter.

[Latte]

No cant see anything between the grille and the condenser so fairly sure thats clogged.

Can just see daylight looking through certain parts of the coil from inside after i blasted it with OFN so do think theres anything in between as there is no easy access. Looks like im going to get a shock when the air intake grille comes down

Regards

Latte

[Brian_UK]

If the grille comes away without too much hassle it might be worth while getting some filter media and getting it fitted to the back of the grille for future protection.

[Latte]

Thanks Brian,

Such a good idea i tried to give you a rep pont but apparently i have got to spead the love more :-)

I Know they have a big roll of some in the Parts Dept at Head office, i will get them to send some down

Thats

Latte

[Brian_UK]

If they're in the mood for spending money it could improve things if some form of hood/cowl was built over the intake grille.

This would help deflect the heated discharge air away and encourage the cooler air from lower down.

Doesn't need to be elaborate; a piece of sheet metal with the ends bent over to form a wall bracket at 30-45°.

[Latte]

If they're in the mood for spending money .

YEAH RITE !!!!:rolleyes:

Its one of those jobs where a previous contractor has been in various times over the last year and never been able to sort (Unit wasnt doing anything) and took me about an hour on the phone to Hushon going over the wiring diagram (who were incredably helpfull and anyone on the forum from them please thank technical) to realise that there are manual HP and LP switches hidden away. Hp's had popped and cut out the control circuits
Thats another excessive mobile phone bill im going to get this month :rolleyes:

I seem to be getting a lot of these, another contractor cant sort jobs at the moment. Thankfully most of them come under Franks remit so i know where to go for info

Regards

Latte

[back2space]

If its pretty easy to reach the condenser after you take the grille off filter media might just clog up too quickly and if the client dont get regular servicing they are back to square one again.

Perhaps explain that they need the system cleaning every 6months or so.

Would be interesting to see some pics during the job etc.

[Latte]

No Probs, i will chase the job up as its probably had to go to quote but will take photos when we do it

[back2space]

Thanks Brian,

Such a good idea i tried to give you a rep pont but apparently i have got to spead the love more :-)

I Know they have a big roll of some in the Parts Dept at Head office, i will get them to send some down

Thats

Latte

Was going to suggest the same thing but thought might get jumped on as thought condensers were supposed to have unobstructed air flow you see.

[Latte]

I would guess this hasnt been done in YEARS, unfortunatly its a new contract so we have no record of whats being done but cant imagine anyone who has been previous to do a maintenance has gone to all the trouble of removing vents, its not something you can do by youreself anyway

[Brian_UK]

If its pretty easy to reach the condenser after you take the grille off filter media might just clog up too quickly and if the client dont get regular servicing they are back to square one again.

Perhaps explain that they need the system cleaning every 6months or so.

Would be interesting to see some pics during the job etc.
What I have done in the past is to have sheet filter media fitted to the back of the grille for coarse dirt collection and then had pleated panel filters after that for the fine dust collections.

If the client can be convinced that it is cheaper to have the filter media changed on a regular basis (time will tell how often) than losing the plant due to clogged coils and the high expense of cleaned them.

[back2space]

Spot on Brian but my understanding is that condenser coils need to have 100% airflow, would filters not reduce this airflow?

Im probalby wrong but its not often you never see outdoor units with filters on them, I assumed that was why.

[Latte]

Finally got back to site today. Once covers moved found condensers COVERED but a thick carpet of dust that we peeled off like a blanket. Sprayed the coils with RTU and hey presto, no more HP trips and Shop temp now hits 18 degrees.

Pictures 1,3,4 show before clean
Pictures 8 & 9 after clean

Regards

latte

[sedgy]

hi latte,
well done, but having struggled in restricted accsess on a-c units many times , I am glad that I have recomended that the units be moved outside on the roof it has saved me many hours strugling in the hot summers

[Latte]

They clearly hadnt been done for years but the problem is that its such a pain in the backside and also a 2 man job its hard to do it on a maintenance by yourself.

What i have done however is, another client of ours has had cardboard leaflets made up (More for F-gas reguations than anything else) which you have to fill in each time you are on site working on a piece of equipment, showing job no, date and work carried out. i have filled one of these out and left it on the control panel so if no-one moves it :rolleyes: at least there is a record on site of when the air vents were last pulled out and condensers cleaned. Ive also tightened all the belts, changed the evap filters and given it the full billy.

As you can see from the pictures, i didnt climb in and get dirty, i let one of my younger, more energetic collegues climb in a do it.

Regards

Latte